Linear amps are a bane to HF in the 21st century. After re-entering HF after a 20 year hiatus (running a Yaesu FT-840 and stealth ZS6BKW because I live in an antenna restricted area) the first thing I noticed is the ole’ boy channel hogs that used to be confined to 80 meters, have now proliferated to 40, 20, and even 10 meters on occasion. They absolutely ruin QRP and most 100W stations with as much as 200 kilohertz splatter which really affect SDR radios like the ICOM 7300, especially at field day events. 11 meter citizens band was ruined by sloppy operators indiscriminately using linear amps. Fifty years later and upon retirement getting my general and amateur extra, I see the exact same thing happening to HF. Most hams are now urban dwellers and thank goodness for the new digital and VOIP modes, since there is absolutely nothing on local repeaters. I live in Houston and only the club repeaters are being used for nets. The rest of the time all you hear for hours is station ID. The ARRL and FCC need to reexamine power limits and band usage for amps over 400 watts. There is enough RFI and QRM to deal with in addition to HOAs who make external placement of ANY outside antennas very difficult. As the FCC consistently emphasizes, use the MINIMUM amount of power needed to make the contact. Most of the old timers, especially the Deep South don’t grasp this concept and could care less about best amateur practices and techniques.
This is by far the biggest rabbit hole that I have found in amateur radio. It really comes down to money. Solid state amps are far easier to use, but they cost a fortune, and they're all 12V requiring like 80 amps, so you have to buy an obscenely expensive new power supply for it. For whatever reason, most tube amps can be had with 120 AC power, so you just plug it into your wall socket. However, the tradeoff is that, with tubes, you have to tune, tune, re-tune, tune.... every time you so much as change frequencies. So that "hit the magic button" only works with a solid state amp. If you have to re-tune every time you change frequency and/or band, then you need a dummy load that can handle the increased wattage which is another two hundred bucks. For either type of amp you will need a larger capacity tuner, which will set you back another five hundred bucks or so. Then, depending on what type of HF antenna you use, you might have to upgrade that as well. Finally, the tuning is all transmitted watts-dependent which means that you also need a new watt meter that will handle the increased power. You'll also need another fifty bucks worth of cables and adapters to make your new rig work. So, I guess what I'm saying is, If you're not willing to shell out about $2500 bucks, then don't even get started down the amp road.
Those of us who live with a crappy HOA and a ranch style house (no appreciable height even if we can hide the antenna) can't improve our antennas very much. I'm still not going to get an amp, so I have to fiddle with the antenna as much as permissibly possible. I've tried end fed, I've tried off center, I'm currently using a 67 ft dipole that runs right along and under the roof hangover. It's terrible, but so far it's the best of the three. My next project is a dual hamstick 20m dipole.
Q. When should get a linear amplifier? A. When you've done everything Ham has to offer and your radio soul is dead. Here's some analogy... I own two yachts. My 48 footer is lovely, sails well and is very comfortable to live aboard. I lusted after her for about two decades before I could finally afford her. Now that I've got her she's expensive to run, maintain and berth. She's very forgiving in wind and you can be quite a sloppy sailor and not come to too much harm. She stays moored most of the time. My other yacht is a 1966 Contessa 26... at 26 foot she's cramped, you have to crouch below, she's real low to the water and you're certainly gonna get wet... she's also one HECK of a lot of fun! You're "closer to the wind" so she makes you a better sailor... handle her 'just right' and she'll fly! I get out in her far more often. But... before I had either yacht, I used to sail one man dingies... they're only slightly less wet than swimming, they'll take any opportunity to dump you in the water. Everything you do, you see the effects immediately. Every mistake will punish you... but get it right and you're rewarded instantly !!! The best sailors I know were Dingy sailors as you really need to be on your game, they'll teach you EVERYTHING you need to know about sail... they're also some of the most fun you can have outdoors. Guess which two have given me my fondest memories ; ) QRP is like that. It may be frustrating running on 5w... but you cannot get by on sloppy antennas and practices. You're gonna need good ears... and you're always going to be tweaking with antennas to squeeze the best out of such a tiny radio. It's frustrating and rewarding in equal measure... but you know instantly when you're impaired your setup, even slightly. So, QRP makes you a better ham! It's where the maximum fun and reward is at. Now, you may be lusting after the full license and 1,500W, just like I lusted after my 48-footer. But there's hidden cost... you're no longer feeling the imperfections in your setup. You're no longer getting the same satisfaction at squeezing out those DX contacts! Sure, if you use radio professionally, it makes sense. If you're lazy or the hobby doesn't excite you anymore, it makes sense. But moving to big watts is like giving up on your childhood wonder. QRP for life, baby! Linear Amplifiers are for club shacks and grumpy old men HIHI 73 de M6UDS
I would recommend using a crossneedle on my output line, before deciding you need more power... it will tell you if you have any power at all, or if you are shining a light into a mirror.
Don't forget us Advanced Class Hams. After 65 years as a ham and never having an amp. I am considering getting an amp. Most reason because band conditions suck and most of the Hams I can hear are using 500 or more watts. Thanks for all the information that you provide. WB7ORB
100w to 1,000w is 10dB. This is an increase of LESS THAN TWO S-Units on the receiving side (one S-unit requires 6 dB). Stay with 100W. Optimize your antenna. Also use some audio compression if you have it. Great video - I like your advice that you need optimize your system if you cannot be heard when you hear them. I love verticals, low takeoff angle!
A 10 dB increase in power is a 20 dB increase in voltage. A "calibrated" S-unit is a 6 dB change in voltage, corresponding to a 3 dB change in power. If you were @ S9, a 10 dB power increase will bring you to S9+20dB over S9.👨🏻
Remember also that many older tube amps have significant switch voltage and current on the PTT line. If you plug it right into a modern rig you can easily blow up the PTT switching mosfet Instead you need to create a transistor/relay arrangement to interface the 2 together so that the relay can sink the current from the PTT line on the amp
Wow - somehow I missed this video two years ago! What a great collection of information for all hams - reinforcing what some of us 'thought' and now need to put to action. Thanks Dave.
Not always. I had my MFJ-1979 on my Jeep with my IC-7300. I dialed in my ALC. it’s still low at times, but when I dialed back my bass on my voice. I got Lithuania over someone that had an amp. I got in at the right time and my audio was good. I worked several states. I never had that luck. All because I worked on my setup, audio and ALC. it’s crazy how 100w is enough to make contacts. Now I want to fine tune my antenna, coil, get 40m and then add 300w.
I have been thinking about an amp at some point (not for a while yet). First I'm going to upgrade the antenna to see if I can improve the reception first. But this was very helpful. Thanks!
thanks Dave - great advice as ever. We're limited to 400w in the UK and that feels like plenty. Funny thing is though - I get as much pleasure from 'not' having to use my amp with 30-100watts - (use only what you need) as I do when when i need to switch it in and complete a contact. running an amp all the time becomes a new normal and you forget the benefit of your investment :-)
Hi Dave, Very good info. Another suggestion, if the transceiver has a built in antenna tuning unit, is to turn it off when using an amplifier. Stay safe. 73 WJ3U
Excellent video David you definitely covered some of the pitfalls that I encountered when I first looked at getting an amplifier. Especially the bit about putting the antenna tuner after the amplifier and not between the amplifier and the radio .. I did that once and I called my Elmer asking him why I couldn't get it to tune lol
As always, Dave, very well presented. I appreciated the solid review for an old timer who hasn't looked at the literature lately and who has "forgotten" some of the necessary good stuff. One quick note. As of April 2024, Martin Jue sent out a quick thank you note to all the suppliers letting them know that MFJ (and its ancillary companies - Ameritron, etc.) is closing up shop after over 50 years in business. Mr. Jue is retiring. MFJ will continue to sell through its existing inventories, but the day will come when it is no more as a supplier once inventories of various products exhaust. You might want to update this video with that information.
I'll add one more scenario in which you might need an amp: if you have an icom 7100 and when you bought it you didn't know that it was power challenged on SSB and you barely every put out more than 40W PEP even on a perfect match antenna! (I'm in this situation now and actively looking for an amp, thinking of JUMA PA1000+ and would drive it at 400W since it's my limit here but ready in case that changes)
That's great David. I am always learning with you however your question "If you can hear the stations but they cannot hear you, it's time to get an amplifier".....Hmmm....not always. I am not an experienced operator and have only a 100W station with a Dipole antenna. I have made some amazing QSO's with this setup (just the other day had a QSO with OF73ELK, in Finland on 15 metres...and I am in Auckland, New Zealand......I was getting there 4/5). What if the station I am trying to reach has a directional antenna pointed to the opposite direction I am broadcasting ? This happened many times with me. It doesn't matter what I do, they will not get back to me.
Nice vid. One option to save a little $$$ (that you didn't discuss much) is to purchase a used amp. Sometimes you can pick up a 40- or 50-year old amp for below $1K. Also when going with tube amps in particular, it's important to make sure that replacement tubes can be had for a reasonable price. Like the "Eimac" case you mentioned, many tubes are becoming difficult/impossible to find. Many folks now are now considering solid state for just that reason.
This is a topic that I am in the middle of navigating. Been a HAM all of about 9 months 😁, and have spent a significant amount of time, effort, and money on good coax (lmr-400 ultra flex), multiple 8’ copper ground rods, individual lightning arrestors for each coax (mainly for general grounding, not lighting), station ground, flat strap grounds, minimal AC power, primarily DC power (including my lighting etc), ferrite on all cables, 34’ mast with an inverted L config Chameleon Emcomm III Base (130’) antenna. Finally I run my RX signal through a Heil PRAS system to pull the transmission out of the noise. With all of that I just cant always get through. However, I consistently work coast to coast (not into DX anyway) from Oklahoma. The consideration is based on my frequent HF Net participation where I sometimes fight to get contacts for Contact Nets or TX strong enough for rag-chew nets. Always something to consider. I like the simplicity of a 100w rig without amps, tuners etc
Other people have pointed this out: in VK & G (Australia and the UK) two places I am licensed we are allowed 400W pep and around 100W AM. The difference between an actual 100W pep and 400W pep is 1 S point on the receiving stations meter. An amplifier for a 10W radio to 400W pep is only around a 2 and a bit S point increase. I do own amplifiers but I am realistic about the actual effect. I think people get confused by ‘Big’ stations - the ones with huge towers and huge beams that run at (or over) the legal limit that are easy to hear so people think if I get an amp that will be me - but you will need the huge tower and beam and ‘all knobs to the right’ to replicate their signal. It’s made worse by countries with no effective limit on power that you hear on the bands.....
How about NVIS to a broadband antenna for regional EmComm and ALE? Won't that be a good use for higher power to overcome the losses? For example, a terminated antenna such as TFD etc.
Great information Dave thanks for sharing. I noticed in the video up on the shelf behind you is a Hallicrafters S 20 R Sky Champion radio, I have the same model and mine is still in working order. 73's David W5DPV.
Hi I’m Mike W8MLD, I use an inverted L and rarely need to power up my AL-811H. I have a load of radials, probably close to 60. It is a very good antenna and I have very good ground, loads of clay and electrolytes. Most of the radials are buried, but I keep adding more as time goes on. Your advice is spot on when you need to add an amp. I usually only use my during contests and when conditions are bad. I get about 730 watts on 160 down to 600 watts on 10 meters. It does the job when needed, and it’s well priced both new and used. I am thinking of swapping out the 811As for 572Bs if I ever find a matched quad. I find the tube based amplifiers sound better to me.
I think one point that should be emphasized is there isn’t that much difference between 600 and 1500 watts. That is only 4 db difference and only amounts to just about 3/4 of an S unit. The biggest difference in the ability of the other station to hear you is going to be the jump from 100 to 5 or 600 watts, but going to 1200 or 1500 watts doesn’t make that much of a difference. It might for contesters trying to break a pileup but in most circumstances it won’t matter.
I am working a portable station with 100 watts doing POTA(Parks On The Air). As we’re all using 100 watts or less are there methods of working through the resulting pileup to get your call picked? Thanks for your help. Fred W2FTR
Where there's a pileup the usual strategy is to "listen up" 3 to 5 khz or listen down; you don't even need to announce that you are doing so. Someone that is clever will transmit 3 to 5 up from your transmitted and you are listening 3 to 5 up. How exactly this is done depends on the radio. A fairly simple approach is the other person dials the VFO up 3 khz but then uses "RIT" receive incremental tuning to go down to your transmit frequency. When she transmits it will be on the dial frequency 3 khz above yours. You, on the other hand, don't touch the big dial but use RIT to listen up 3 khz. RIT has rather limited range so this is where you can have dual VFO's one for receiving and one for transmitting. Some radios have a TX Offset which is the same thing as RIT except for transmit. By the way it is also a handy technique for FT8 digital mode on the assumption that the other person is using WSTJ-X and has -the usual 3 khz bandwidth. Set your transmit frequency on a clear spot and your signal will be heard because most people transmit on the very same frequency they heard something. The pileup goes nowhere but you are transmitting in a clear frequency knowing WSTJ is listening to the entire 3 khz audio passband.
I can hear a lot of stations from my home none can here me. I can't put up a good antenna, and I don't think an amp is going to help. I'm going to go do pota very soon, but changing your location is another solution it could even be at a local park that doesn't qualify for pota. Investing in a battery and a portable antenna and maybe a solar panel might be a cheaper and better option.
Tons to learn here. You have probably forgotten more than I have learned in your time. Getting your gain-structure well matched from exciter to linear amp has always been a golden rule in any kind of audio device set-up. Speaking of "excitor" this is a great post from you , You are just bubbling with laying the law down I just love it LoL 😜🤪😳
I'm running a temporary Chameleon MPAS 2.0 Vertical antenna with 20 ground radials and it is working good for me. I purchased my first HF radio; the Yaesu FT-DX10, back in November of 2021 and since then I've made over 6000 digital contacts with a few in Phone mode. My question to you is will an amp help me out in contesting. When I enter a phone contest, I hear the station to almost full quieting but transmitting at 100 watts, 150 ft. of Messi Paloni cable which is comparable to LMR-400/500, they are reporting back to me a 54, 53, 52. They are a 59+ over 10 that I can hear. I assume they are using more than a 100 watts of power. It usually takes me 5 or so minutes to make a contact to them while yelling loudly for them to hear me. Will an amp benefit me during those contests so I don't have to constantly yell at them to be heard. Any advice would be greatly appreciated! 73's from N3NQP!
As soon as you get your General license! (If your going to make lots of contacts) and you have at least a fan dipole in a inverted V with the driven point up at least 30’! You will talk to the world, I do…. Don’t forget about good coax!
Height is its own amplifier! Tall trees are the best for antennas made of wire. I am lucky to have two 70' cedar trees on my property. I live on a 550' hill, too. 80 watts got me a 59++ signal report almost every time except when the band is dead. Even then, I could raise a VK station on a dead 15 meter band by constant three minute call and make the contact and get a QSL card proving it. I made a call on 6 Meters from Montgomery, AL to Scotland on 50.537 SSB and have the QSL card to prove it. Height is cheaper than an amp !!
I don't always talk on the radio to locals, but when I do I use a 5/8ths wave GP and a 12ax7 modulator into a klv 1000 and a Galaxy Saturn at 1 watt dk. Of course there is that foot pedal down there if I need a little more.
Thanks again Dave. Once again you provided a video that applies to what is on my mind. Makes me wonder if you are clairvoyant 🤔. I am in a similar situation in your letter. I have a Hustler 4btv, a BMT-DX-OCF-HP40 - Buckmaster OCF Dipole Antenna and an End-Fed Antenna. A tower is also not an option. I've been looking at the AL-811H, but also wonder if the MFJ Cobweb antenna might be a better idea. Thanks again for all the info you provide. Have a great New Year and a healthy 2021.
@@kc8wvg I had just bought an old kenwood from about 1980 6 months ago. I was getting stuff from south america. I made some clear connection with someone about 800 miles away. My radio didn't last long enough to really make a judgement call on the Hustler. That made two used radios I've bought that crashed or quit working. If I get another$1400 I'll buy a new radio.
@@joseph2219801 Thanks. I've had some success with mine, but it was difficult for me to tune on 20 meters. Also, even thought I laid out about 50 radials I'm thinking that my chain link fence has given me most of my problems. I bought an IC7300 and really have had great contacts with the OCF and wire antennas. Small city lot has me thinking of replacing the Hustler with either tek-tenna or a Cobweb. Both have good reviews. Cheaper than replacing the fence😁.
The question I ask is do you really need an amplifier . My answer not really if you have a poor antenna system . My advice is to have the tuner at the feed point of the antenna . Look even at less than 5 watts AM or 12 watts ssb can get you half way around the globe and I know this while only on the CB radio in California and again in Idaho . 73's from kn4kbh .
Great as always Dave! This was exactly my experience. I heard lots of signals, but wasn't getting out. Antenna upgrade was first, then the amp was next.
I have a Collins 30L-1 that I had been using but it's a vary nice old classic and I didn't want to run it hard . So seeing I wanted an amplifier that could regularly do 1kw with out stressing it so I went with an Acom 1500 . Even though I have all this power at my disposal it's still a challenge to try to get the contact with just 100 watts . Great video 73 n8wxt .
How come when you tune an antenna tuner again for 1to1 when you transmit more power. Say you tune to 1to1 with five watts and then when you go up to 100 watts you have to retune.
The match does not change but the reflected power is difficult to detect when forward power is low. (The diodes in the detector circuit need above about 0.3v to begin conducting) In the unlikely event that the match really changes with power it points to a problem, perhaps a ferrite saturating or overheating, perhaps a flashover.
The inter-electrode capacitance in the power MOSFETS will change slightly depending on drive level. As these MOSFETS are part of the output circuit it has the potential to *slightly* change the tuning; this is the principal of the varactor diode where the variability of the capacitance is enhanced. ruclips.net/video/M8F6-VMXQVE/видео.html 5 minutes into the video he explains that changing the voltage changes the depletion region and consequently decreases capacitance.
Another point: You'll get a lot more power and reach out of your 100w transceiver if you work CW instead of SSB, because of the concentration of output energy in a very narrow signal.. Yes, you'll have to learn CW Morse, but you'll be able to cover the world with a good to excellent antenna...
Hey Quick Question Here im looking at doing mobile work (with an Ht [i wanna "upgrade" from my baofeng uv5r] dont know yet to which one) and dont wanna take my 50w mobile w me but am looking to get maybe 25watt-ish out dualband ist this a realistic idea, and is there an amp i can use? please give plenty suggestions as its hard to get most amps here i Germany 73`s (For the why? because all exept 2 Spots where i plan on going mobile have lots of trees that ill need to penetrate but they have the benfit of the Hight so i dont want to let them go out of my mind already)
Hi Dave ‘I’m one of the ones who needs one of those expert professionals you alluded to about your yeasu on the shelf.I have a 1950s tube type Military transmitter/receiver that puts out a whole 7watts of AM power .it’s not 50 ohms…. has a plate and Load on the transmitter. I would just like to get a small amp for this just to be heard.your thoughts,tnks.jim
When you asking about if you're antenna is good enough, you should always ask where do you want to have contact to! If you working dx, yeah your vertical is a great choice for the "price point" relative low radiation angle, if you're budget or situation doesn't not allow you to put up a mast. If you working local, under 600 miles, the radiation pattern might be too low, and you might have better results on 80 and 40m with a low mounted dipole With dx You can still play around with vertical setup with some half yag or stack verticals, half yagi is for my understanding single band solution and you need to have good ground for every element does mean you build it for one direction. Stacking verticals you can aim your singnal with phase adjustments, with only two 1/4 verticals a 1/4 way from each and driving other in 90 degrees, you get a nice wide pather with a nice good back to front attenuation, (great if you have nice coming from one direction) but it will gain you only 3db and its double the work, and you might need to doo some magic to get it multi band. Personally for my situation, I Drive only a mobile station, (yeah putting up some antennas for some events) A mobile station is always a compromise, I build some antennas my self from fishing poles. In a mobile station you usually hear better than you can transmit on hf, that's mostly because most base stations are having higher noise floor with the bigger antenna so on the receive side its not that much worse, (it is but not that much) but transmitting I do have problem to get out. have a project for 1kw mosfet amplifier, one of those 50V pallet, relatively inexpensive way to go, need to mount it on a heat sink and do the txrx relays. Power I'm getting from a combo off 230v 1000w inverter and 50V power supply (yeah, I'm from Europe so we deal with 230v) this system should give me closer to 800w on ssb if my math ia right (yeah you can drive the 1000w inverter little over the spec for a short time) I'm going to build the filter for 10, 12 and 15m so the amp will never work down on the long bands. I'm rocking a camper wan so I do have space to install the gear, having abaut 100A alternator and some extra battery capacity to not be a problem with current spikes
Oh gosh Dave you are so FUNNY on this video! "The Lights Do Dim". Great point about the reflected power back from the antenna and feed line to the Tuner.... Thanks, Art
Hi Dave at about 19 min you mention that QST states a G90 and an amplifier will exceed spurious emissions I searched and could not find it on ARRL search, can you please site the exact article that you reference. I would also refer you to an Amplifier Build kit that I have built that will run on 115volts regular household power and produce 1.2KW. it is a KM3KM.
I can't have a ham radio amplifier for three reasons: One, amplifiers are _expensive;_ two, they typically need more current than what any of the circuits in my dwelling can supply; and three, you cannot use an amplifier in a portable station.
Dave,. Any thoughts on a sky wire antenna as described in the ARRL Antenna Book. It's cut for the lowest band possible, in my case 160, one full wave divided by four and put up in a square. Feed it with ladder line should work all the way up through 10 meters. Should have gain as you go up from 160. Can't do a vertical due to really rocky soil, tree roots everywhere, and can't do a tower. I want access to all bands including 60 and will be doing MARS again. Is there something better. W8PEF
You have to have an amp if you want to work every night on 40, 80 and 160m. 40m international working Australia, Asia and Russia you have to run power and best around at least 1k. But if you want to only work the states and have hard times doing so with the lightening stay at 100w. 10m is about the only band an amp isn't much difference. Get a 572B amp for an instant on tube amp. Ceramic tubes you have to wait a minute or more for the tubes to warm up before transmitting without ruining the tubes.
I found an article in March 2020 QST on the G90. It says "we do not recommend using a power amplifier" how does this mean it will produce spurious emissions that will violate FCC Rules?
It stated in the lab notes that it doesn't meet FCC harmonic and spurious emission standards and phase noise is higher than they'd like to see. At QRP levels it probably doesn't cause too much problem. An amplifier makes it worse. If you input a dirty signal into a broad band amp, it's not going to get cleaner.
I'm surprised that in this discussion of power amps there was no mention of the inverse square law. Only minor mention of the rate of return by increasing power by a multiple of ten and by comparison of power increase seeing very minimal difference on the receiving end. Once we're all running a KW class station the next logical step is 5 or 10 KW. It's an interesting mindset regarding power amp. If you want to put the inverse square law to the test start a QSO with 100 watts and ask for an RST. Then drop down to 10 watts and ask for one more RST without disclosing what change was made. I think it will surprise many. 73's P.S. as you may have already guessed QRP Op here...
Hi Dave, 73's from the UK, I'm due to start the foundation course next month, about time 59yrs young!, anyway, as You probably know the 1st UK licence will limit Me to 10watts, My question is, Will that be enough power to communicate with the other side of the Planet?, I have no reason to reach further!, Or do I?, Keep up the great work Sir, Love Your videos, regards Stew.
This may be an odd question; I'm fairly new in the HAM world, only got my license about a year ago, and I'm on social security... Since HAM equipment is rather expensive (yes, even used...) I want to build a base station. I am an electronics engineer, so that side of designing / building isn't really the issue, but what features should a reasonable entry level HAM transceiver station have? And are there any good resources for design tips / feature tips etc. ? I mean, other than this channel of course :p Wouldn't ask anything here if I didn't find the information on this channel really informative and useful ;) I don't know if it makes a difference; I'm in the Netherlands.
Great job Dave, I have just aquired a AL 811 H 800 watt amp. I have an HyGain AV-680 antenna but as you said you can't work them if you can hear them. A tower is not an option but even with what I think is a good antenna I don't hear very much DX. I bought the amp from a club member that is an engineer and got it at a great price. but think it will help with getting through to people I can hear but what about those that I can't hear. I live in South Dakota and have been told that because of my location hearing DX can be a problem. Is there anything elese I can do to improve my reception on my IC 7300? Thanks, Jeff KE0KRO
Yes, they work fine. If you are going to run on modern radio into the Heathkit amp, then you may wish to temporarily put it tuner between the rig and the amp to make sure that the to match. You can also use an antenna analyzer on the input to the antenna. You will likely be able to use the plate and tune controls to tune your antenna. Also watch out for how high the AGC voltage can get. Also check the voltage across the transmit input to the amplifier. This voltage must be grounded when the rig wants to transmit. If it's more than 5 V, and takes more than a few milliamps, you may want to put a relay in the circuit.
@@davecasler I plan on putting my antenna tuner in the loop between my transceiver like you suggested. I'm a veteran HAM on a budget, I have a Alinco DX SR8. Being new at HF after just getting my General rating. I would drop my radio down to it's lowest output power setting before using the amp...correct?
If you make contacts with contesters, you really should submit a 'check log' for those contacts. They are vitally important. Get a little, give a little. It's important.
I think fewer people would get amps if they knew which antennas were better, but it's so complex they go for the gas pedal or go what I do and test every antenna under the sun.
Depends, they both have their own strengths and weaknesses. A beam will hear better and transmit better, in one direction. You will talk to different people with a vertical because of the radiation angle so the distance you get will be different. It is easier to get multiple bands on a vertical.
And the audience agrees: MAYBE! Or is that sometimes? Vertical antennas have a low departure angle which is great for long distances. The big difference is polarization; beams are usually set up horizontal and want to talk only to horizontally polarized antennas of any kind. Verticals are, of course, vertically polarized (as are loops that are upright). At higher frequencies the effectiveness of beam antennas is much improved and height above ground not quite as stringent. Over long distances that have bounced, polarization can rotate so the exact polarization isn't as important.
@@thomasmaughan4798 The polarization of the upright loop depends on where the feed point is. IIRC fed at the bottom it's horizontal. Fed on the side it's vertical.
Linear amps are a bane to HF in the 21st century. After re-entering HF after a 20 year hiatus (running a Yaesu FT-840 and stealth ZS6BKW because I live in an antenna restricted area) the first thing I noticed is the ole’ boy channel hogs that used to be confined to 80 meters, have now proliferated to 40, 20, and even 10 meters on occasion. They absolutely ruin QRP and most 100W stations with as much as 200 kilohertz splatter which really affect SDR radios like the ICOM 7300, especially at field day events. 11 meter citizens band was ruined by sloppy operators indiscriminately using linear amps. Fifty years later and upon retirement getting my general and amateur extra, I see the exact same thing happening to HF. Most hams are now urban dwellers and thank goodness for the new digital and VOIP modes, since there is absolutely nothing on local repeaters. I live in Houston and only the club repeaters are being used for nets. The rest of the time all you hear for hours is station ID. The ARRL and FCC need to reexamine power limits and band usage for amps over 400 watts. There is enough RFI and QRM to deal with in addition to HOAs who make external placement of ANY outside antennas very difficult. As the FCC consistently emphasizes, use the MINIMUM amount of power needed to make the contact. Most of the old timers, especially the Deep South don’t grasp this concept and could care less about best amateur practices and techniques.
This is by far the biggest rabbit hole that I have found in amateur radio. It really comes down to money. Solid state amps are far easier to use, but they cost a fortune, and they're all 12V requiring like 80 amps, so you have to buy an obscenely expensive new power supply for it. For whatever reason, most tube amps can be had with 120 AC power, so you just plug it into your wall socket. However, the tradeoff is that, with tubes, you have to tune, tune, re-tune, tune.... every time you so much as change frequencies. So that "hit the magic button" only works with a solid state amp. If you have to re-tune every time you change frequency and/or band, then you need a dummy load that can handle the increased wattage which is another two hundred bucks. For either type of amp you will need a larger capacity tuner, which will set you back another five hundred bucks or so. Then, depending on what type of HF antenna you use, you might have to upgrade that as well. Finally, the tuning is all transmitted watts-dependent which means that you also need a new watt meter that will handle the increased power. You'll also need another fifty bucks worth of cables and adapters to make your new rig work. So, I guess what I'm saying is, If you're not willing to shell out about $2500 bucks, then don't even get started down the amp road.
Those of us who live with a crappy HOA and a ranch style house (no appreciable height even if we can hide the antenna) can't improve our antennas very much. I'm still not going to get an amp, so I have to fiddle with the antenna as much as permissibly possible. I've tried end fed, I've tried off center, I'm currently using a 67 ft dipole that runs right along and under the roof hangover. It's terrible, but so far it's the best of the three. My next project is a dual hamstick 20m dipole.
Q. When should get a linear amplifier?
A. When you've done everything Ham has to offer and your radio soul is dead.
Here's some analogy...
I own two yachts. My 48 footer is lovely, sails well and is very comfortable to live aboard. I lusted after her for about two decades before I could finally afford her. Now that I've got her she's expensive to run, maintain and berth. She's very forgiving in wind and you can be quite a sloppy sailor and not come to too much harm. She stays moored most of the time.
My other yacht is a 1966 Contessa 26... at 26 foot she's cramped, you have to crouch below, she's real low to the water and you're certainly gonna get wet... she's also one HECK of a lot of fun! You're "closer to the wind" so she makes you a better sailor... handle her 'just right' and she'll fly! I get out in her far more often.
But... before I had either yacht, I used to sail one man dingies... they're only slightly less wet than swimming, they'll take any opportunity to dump you in the water. Everything you do, you see the effects immediately. Every mistake will punish you... but get it right and you're rewarded instantly !!! The best sailors I know were Dingy sailors as you really need to be on your game, they'll teach you EVERYTHING you need to know about sail... they're also some of the most fun you can have outdoors.
Guess which two have given me my fondest memories ; )
QRP is like that. It may be frustrating running on 5w... but you cannot get by on sloppy antennas and practices. You're gonna need good ears... and you're always going to be tweaking with antennas to squeeze the best out of such a tiny radio. It's frustrating and rewarding in equal measure... but you know instantly when you're impaired your setup, even slightly.
So, QRP makes you a better ham! It's where the maximum fun and reward is at.
Now, you may be lusting after the full license and 1,500W, just like I lusted after my 48-footer. But there's hidden cost... you're no longer feeling the imperfections in your setup. You're no longer getting the same satisfaction at squeezing out those DX contacts!
Sure, if you use radio professionally, it makes sense. If you're lazy or the hobby doesn't excite you anymore, it makes sense. But moving to big watts is like giving up on your childhood wonder.
QRP for life, baby! Linear Amplifiers are for club shacks and grumpy old men HIHI
73 de M6UDS
I would recommend using a crossneedle on my output line, before deciding you need more power... it will tell you if you have any power at all, or if you are shining a light into a mirror.
Don't forget us Advanced Class Hams. After 65 years as a ham and never having an amp. I am considering getting an amp. Most reason because band conditions suck and most of the Hams I can hear are using 500 or more watts. Thanks for all the information that you provide. WB7ORB
As I've heard "Life is too short for 100 watts and a wire"
If band conditions "Suck" I was told an Amp is still useless.
@@onemorething100 Now band conditions great and my new amp is great.
@@onemorething100..and you were told correctly!
100w to 1,000w is 10dB. This is an increase of LESS THAN TWO S-Units on the receiving side (one S-unit requires 6 dB). Stay with 100W. Optimize your antenna. Also use some audio compression if you have it. Great video - I like your advice that you need optimize your system if you cannot be heard when you hear them. I love verticals, low takeoff angle!
A 10 dB increase in power is a 20 dB increase in voltage.
A "calibrated"
S-unit is a 6 dB change in voltage, corresponding to a 3 dB change in power. If you were @ S9, a 10 dB power increase will bring you to S9+20dB over S9.👨🏻
Who cares about S units? You need to be heard above the noise!
Remember also that many older tube amps have significant switch voltage and current on the PTT line.
If you plug it right into a modern rig you can easily blow up the PTT switching mosfet
Instead you need to create a transistor/relay arrangement to interface the 2 together so that the relay can sink the current from the PTT line on the amp
You are absolutely correct.
Wow - somehow I missed this video two years ago! What a great collection of information for all hams - reinforcing what some of us 'thought' and now need to put to action. Thanks Dave.
"When Can I Get an Amp for Ham Radio?" Tuesdays are pretty good.
that got a good chuckle out of me :D
Not always. I had my MFJ-1979 on my Jeep with my IC-7300. I dialed in my ALC. it’s still low at times, but when I dialed back my bass on my voice. I got Lithuania over someone that had an amp. I got in at the right time and my audio was good. I worked several states. I never had that luck. All because I worked on my setup, audio and ALC. it’s crazy how 100w is enough to make contacts. Now I want to fine tune my antenna, coil, get 40m and then add 300w.
I have been thinking about an amp at some point (not for a while yet). First I'm going to upgrade the antenna to see if I can improve the reception first. But this was very helpful. Thanks!
With better (more efficient) antenna you improve transmitting also! I would avoid an amplifier as long as possible.
thanks Dave - great advice as ever. We're limited to 400w in the UK and that feels like plenty. Funny thing is though - I get as much pleasure from 'not' having to use my amp with 30-100watts - (use only what you need) as I do when when i need to switch it in and complete a contact. running an amp all the time becomes a new normal and you forget the benefit of your investment :-)
Thanks for all your time and effort you put into these videos 📹 👏 👍 I am a fairly new ham for HF and you have helped me immensely
Once again, you are a treasure. Thanks for all your help!
Hi Dave,
Very good info. Another suggestion, if the transceiver has a built in antenna tuning unit, is to turn it off when using an amplifier. Stay safe. 73 WJ3U
Good tip!
An amp with tunable inputs will work with any HF transceiver. Even running a Heath kit SA-2040 in front of your amp cures many problems noted by Hams.
Excellent video David you definitely covered some of the pitfalls that I encountered when I first looked at getting an amplifier. Especially the bit about putting the antenna tuner after the amplifier and not between the amplifier and the radio .. I did that once and I called my Elmer asking him why I couldn't get it to tune lol
As always, Dave, very well presented. I appreciated the solid review for an old timer who hasn't looked at the literature lately and who has "forgotten" some of the necessary good stuff. One quick note. As of April 2024, Martin Jue sent out a quick thank you note to all the suppliers letting them know that MFJ (and its ancillary companies - Ameritron, etc.) is closing up shop after over 50 years in business. Mr. Jue is retiring. MFJ will continue to sell through its existing inventories, but the day will come when it is no more as a supplier once inventories of various products exhaust. You might want to update this video with that information.
I'll add one more scenario in which you might need an amp: if you have an icom 7100 and when you bought it you didn't know that it was power challenged on SSB and you barely every put out more than 40W PEP even on a perfect match antenna! (I'm in this situation now and actively looking for an amp, thinking of JUMA PA1000+ and would drive it at 400W since it's my limit here but ready in case that changes)
Great topic and great advice! Big thanks.
David i vote this episode into the category of “The Best of Og”
That's great David. I am always learning with you however your question "If you can hear the stations but they cannot hear you, it's time to get an amplifier".....Hmmm....not always. I am not an experienced operator and have only a 100W station with a Dipole antenna.
I have made some amazing QSO's with this setup (just the other day had a QSO with OF73ELK, in Finland on 15 metres...and I am in Auckland, New Zealand......I was getting there 4/5).
What if the station I am trying to reach has a directional antenna pointed to the opposite direction I am broadcasting ? This happened many times with me. It doesn't matter what I do, they will not get back to me.
There isn't any general rule in ham radio that doesn't have exceptions!
Nice vid. One option to save a little $$$ (that you didn't discuss much) is to purchase a used amp. Sometimes you can pick up a 40- or 50-year old amp for below $1K. Also when going with tube amps in particular, it's important to make sure that replacement tubes can be had for a reasonable price. Like the "Eimac" case you mentioned, many tubes are becoming difficult/impossible to find. Many folks now are now considering solid state for just that reason.
This is a topic that I am in the middle of navigating. Been a HAM all of about 9 months 😁, and have spent a significant amount of time, effort, and money on good coax (lmr-400 ultra flex), multiple 8’ copper ground rods, individual lightning arrestors for each coax (mainly for general grounding, not lighting), station ground, flat strap grounds, minimal AC power, primarily DC power (including my lighting etc), ferrite on all cables, 34’ mast with an inverted L config Chameleon Emcomm III Base (130’) antenna. Finally I run my RX signal through a Heil PRAS system to pull the transmission out of the noise.
With all of that I just cant always get through. However, I consistently work coast to coast (not into DX anyway) from Oklahoma. The consideration is based on my frequent HF Net participation where I sometimes fight to get contacts for Contact Nets or TX strong enough for rag-chew nets.
Always something to consider. I like the simplicity of a 100w rig without amps, tuners etc
Very well Done Dave you explained in gret detail Thank you 73 s
Other people have pointed this out: in VK & G (Australia and the UK) two places I am licensed we are allowed 400W pep and around 100W AM. The difference between an actual 100W pep and 400W pep is 1 S point on the receiving stations meter. An amplifier for a 10W radio to 400W pep is only around a 2 and a bit S point increase. I do own amplifiers but I am realistic about the actual effect. I think people get confused by ‘Big’ stations - the ones with huge towers and huge beams that run at (or over) the legal limit that are easy to hear so people think if I get an amp that will be me - but you will need the huge tower and beam and ‘all knobs to the right’ to replicate their signal. It’s made worse by countries with no effective limit on power that you hear on the bands.....
Good observation.
Who cares about S units? You need to be heard above the noise!
How about NVIS to a broadband antenna for regional EmComm and ALE? Won't that be a good use for higher power to overcome the losses?
For example, a terminated antenna such as TFD etc.
Great information Dave thanks for sharing. I noticed in the video up on the shelf behind you is a Hallicrafters S 20 R Sky Champion radio, I have the same model and mine is still in working order. 73's David W5DPV.
Mine doesn't work well. It's for display. My aunt gave me one when I was a child, and that's how I discovered the airwaves!
CB operators: "How many watts do you need?" "yes."
I had a good conversation with Croatia from Ft Worth with 60 watts.
Hi I’m Mike W8MLD, I use an inverted L and rarely need to power up my AL-811H. I have a load of radials, probably close to 60. It is a very good antenna and I have very good ground, loads of clay and electrolytes. Most of the radials are buried, but I keep adding more as time goes on. Your advice is spot on when you need to add an amp. I usually only use my during contests and when conditions are bad. I get about 730 watts on 160 down to 600 watts on 10 meters. It does the job when needed, and it’s well priced both new and used. I am thinking of swapping out the 811As for 572Bs if I ever find a matched quad.
I find the tube based amplifiers sound better to me.
Great information! I appreciate your advice. I'm going to look at some antenna options before I consider an amp.
Thank You so much for this. You've answered every question I had and several I didn't know I needed to ask yet. Happy New Years and thanks again
Very well done as always! Appreciate the thoughtfulness that went in to the content! 73 W6AEF
I think one point that should be emphasized is there isn’t that much difference between 600 and 1500 watts. That is only 4 db difference and only amounts to just about 3/4 of an S unit. The biggest difference in the ability of the other station to hear you is going to be the jump from 100 to 5 or 600 watts, but going to 1200 or 1500 watts doesn’t make that much of a difference. It might for contesters trying to break a pileup but in most circumstances it won’t matter.
I am working a portable station with 100 watts doing POTA(Parks On The Air). As we’re all using 100 watts or less are there methods of working through the resulting pileup to get your call picked?
Thanks for your help. Fred W2FTR
Where there's a pileup the usual strategy is to "listen up" 3 to 5 khz or listen down; you don't even need to announce that you are doing so. Someone that is clever will transmit 3 to 5 up from your transmitted and you are listening 3 to 5 up. How exactly this is done depends on the radio. A fairly simple approach is the other person dials the VFO up 3 khz but then uses "RIT" receive incremental tuning to go down to your transmit frequency. When she transmits it will be on the dial frequency 3 khz above yours. You, on the other hand, don't touch the big dial but use RIT to listen up 3 khz.
RIT has rather limited range so this is where you can have dual VFO's one for receiving and one for transmitting. Some radios have a TX Offset which is the same thing as RIT except for transmit.
By the way it is also a handy technique for FT8 digital mode on the assumption that the other person is using WSTJ-X and has -the usual 3 khz bandwidth. Set your transmit frequency on a clear spot and your signal will be heard because most people transmit on the very same frequency they heard something. The pileup goes nowhere but you are transmitting in a clear frequency knowing WSTJ is listening to the entire 3 khz audio passband.
@@thomasmaughan4798
Thank you. Those are wise words and will be printed and kept with the 891!
I can hear a lot of stations from my home none can here me. I can't put up a good antenna, and I don't think an amp is going to help. I'm going to go do pota very soon, but changing your location is another solution it could even be at a local park that doesn't qualify for pota. Investing in a battery and a portable antenna and maybe a solar panel might be a cheaper and better option.
Hi,good interesting video, not quite sure an amplifier is always best, but you have some sound advice, thanks from Rotterdam 👍😷
Tons to learn here. You have probably forgotten more than I have learned in your time. Getting your gain-structure well matched from exciter to linear amp has always been a golden rule in any kind of audio device set-up. Speaking of "excitor" this is a great post from you , You are just bubbling with laying the law down I just love it LoL 😜🤪😳
I'm running a temporary Chameleon MPAS 2.0 Vertical antenna with 20 ground radials and it is working good for me. I purchased my first HF radio; the Yaesu FT-DX10, back in November of 2021 and since then I've made over 6000 digital contacts with a few in Phone mode. My question to you is will an amp help me out in contesting. When I enter a phone contest, I hear the station to almost full quieting but transmitting at 100 watts, 150 ft. of Messi Paloni cable which is comparable to LMR-400/500, they are reporting back to me a 54, 53, 52. They are a 59+ over 10 that I can hear. I assume they are using more than a 100 watts of power. It usually takes me 5 or so minutes to make a contact to them while yelling loudly for them to hear me. Will an amp benefit me during those contests so I don't have to constantly yell at them to be heard. Any advice would be greatly appreciated! 73's from N3NQP!
As soon as you get your General license! (If your going to make lots of contacts) and you have at least a fan dipole in a inverted V with the driven point up at least 30’! You will talk to the world, I do…. Don’t forget about good coax!
Great info and you're looking lots better. Hang in there! 73, Pete-KL7IS
Height is its own amplifier! Tall trees are the best for antennas made of wire. I am lucky to have two 70' cedar trees on my property. I live on a 550' hill, too. 80 watts got me a 59++ signal report almost every time except when the band is dead. Even then, I could raise a VK station on a dead 15 meter band by constant three minute call and make the contact and get a QSL card proving it. I made a call on 6 Meters from Montgomery, AL to Scotland on 50.537 SSB and have the QSL card to prove it. Height is cheaper than an amp !!
I don't always talk on the radio to locals, but when I do I use a 5/8ths wave GP and a 12ax7 modulator into a klv 1000 and a Galaxy Saturn at 1 watt dk. Of course there is that foot pedal down there if I need a little more.
Getting an amp is like unlocking all the cheat codes in video game.
Thanks again Dave. Once again you provided a video that applies to what is on my mind. Makes me wonder if you are clairvoyant 🤔. I am in a similar situation in your letter. I have a Hustler 4btv, a BMT-DX-OCF-HP40 - Buckmaster OCF Dipole Antenna and an End-Fed Antenna. A tower is also not an option. I've been looking at the AL-811H, but also wonder if the MFJ Cobweb antenna might be a better idea. Thanks again for all the info you provide. Have a great New Year and a healthy 2021.
I have the same hustler
@@joseph2219801 How's your Hustler 4btv working for you?
@@kc8wvg I had just bought an old kenwood from about 1980 6 months ago. I was getting stuff from south america. I made some clear connection with someone about 800 miles away. My radio didn't last long enough to really make a judgement call on the Hustler. That made two used radios I've bought that crashed or quit working. If I get another$1400 I'll buy a new radio.
@@joseph2219801 Thanks. I've had some success with mine, but it was difficult for me to tune on 20 meters. Also, even thought I laid out about 50 radials I'm thinking that my chain link fence has given me most of my problems. I bought an IC7300 and really have had great contacts with the OCF and wire antennas. Small city lot has me thinking of replacing the Hustler with either tek-tenna or a Cobweb. Both have good reviews. Cheaper than replacing the fence😁.
The question I ask is do you really need an amplifier . My answer not really if you have a poor antenna system . My advice is to have the tuner at the feed point of the antenna . Look even at less than 5 watts AM or 12 watts ssb can get you half way around the globe and I know this while only on the CB radio in California and again in Idaho . 73's from kn4kbh .
Great as always Dave! This was exactly my experience. I heard lots of signals, but wasn't getting out. Antenna upgrade was first, then the amp was next.
I have a Collins 30L-1 that I had been using but it's a vary nice old classic and I didn't want to run it hard . So seeing I wanted an amplifier that could regularly do 1kw with out stressing it so I went with an Acom 1500 . Even though I have all this power at my disposal it's still a challenge to try to get the contact with just 100 watts . Great video 73 n8wxt .
Thanks for sharing!
How come when you tune an antenna tuner again for 1to1 when you transmit more power. Say you tune to 1to1 with five watts and then when you go up to 100 watts you have to retune.
I'd like to know too
The match does not change but the reflected power is difficult to detect when forward power is low. (The diodes in the detector circuit need above about 0.3v to begin conducting) In the unlikely event that the match really changes with power it points to a problem, perhaps a ferrite saturating or overheating, perhaps a flashover.
@@g0fvt Thank you
The inter-electrode capacitance in the power MOSFETS will change slightly depending on drive level. As these MOSFETS are part of the output circuit it has the potential to *slightly* change the tuning; this is the principal of the varactor diode where the variability of the capacitance is enhanced. ruclips.net/video/M8F6-VMXQVE/видео.html
5 minutes into the video he explains that changing the voltage changes the depletion region and consequently decreases capacitance.
VERY helpful discussion Dave. Thanks for posting it.
Thanks, glad it helped!
Newbe here .... Great advice ... worry about the foundation before the power.
Another point:
You'll get a lot more power and reach out of your 100w transceiver if you work CW instead of SSB, because of the concentration of output energy in a very narrow signal..
Yes, you'll have to learn CW Morse, but you'll be able to cover the world with a good to excellent antenna...
Very timely. I'm about to purchase an amp.
i am hapoy with my ncx3 ..100w
it is working on the badest antenna:)
..good old times.
i like to work on all tube radios.
Who plays the neat clarinet part on your entry and exit theme ditties?
i had a amatuer 300 a long time ago. it was not meant for more than 4 watts of input, but if you fed it around 20 or so it would do over 1000 watts.
Good Content Dave. Always Helpful.
I have a 5 watt radio. :-)
Love the Hermes Lite 2 SDR!
Do I need an amp? Yes.
Hey Quick Question Here im looking at doing mobile work (with an Ht [i wanna "upgrade" from my baofeng uv5r] dont know yet to which one) and dont wanna take my 50w mobile w me but am looking to get maybe 25watt-ish out dualband ist this a realistic idea, and is there an amp i can use? please give plenty suggestions as its hard to get most amps here i Germany 73`s (For the why? because all exept 2 Spots where i plan on going mobile have lots of trees that ill need to penetrate but they have the benfit of the Hight so i dont want to let them go out of my mind already)
Another great show. Thanks for putting it together. John from Lompoc
Hi Dave ‘I’m one of the ones who needs one of those expert professionals you alluded to about your yeasu on the shelf.I have a 1950s tube type Military transmitter/receiver that puts out a whole 7watts of AM power .it’s not 50 ohms…. has a plate and Load on the transmitter. I would just like to get a small amp for this just to be heard.your thoughts,tnks.jim
Thank you, Dave.
I do not think my neighbors would appreciate my using a 1500 Watt light dimmer (humor).
Happy New Year. N0QFT?
When you asking about if you're antenna is good enough, you should always ask where do you want to have contact to!
If you working dx, yeah your vertical is a great choice for the "price point" relative low radiation angle, if you're budget or situation doesn't not allow you to put up a mast.
If you working local, under 600 miles, the radiation pattern might be too low, and you might have better results on 80 and 40m with a low mounted dipole
With dx You can still play around with vertical setup with some half yag or stack verticals, half yagi is for my understanding single band solution and you need to have good ground for every element does mean you build it for one direction.
Stacking verticals you can aim your singnal with phase adjustments, with only two 1/4 verticals a 1/4 way from each and driving other in 90 degrees, you get a nice wide pather with a nice good back to front attenuation, (great if you have nice coming from one direction) but it will gain you only 3db and its double the work, and you might need to doo some magic to get it multi band.
Personally for my situation, I Drive only a mobile station, (yeah putting up some antennas for some events)
A mobile station is always a compromise, I build some antennas my self from fishing poles.
In a mobile station you usually hear better than you can transmit on hf, that's mostly because most base stations are having higher noise floor with the bigger antenna so on the receive side its not that much worse, (it is but not that much) but transmitting I do have problem to get out.
have a project for 1kw mosfet amplifier, one of those 50V pallet, relatively inexpensive way to go, need to mount it on a heat sink and do the txrx relays. Power I'm getting from a combo off 230v 1000w inverter and 50V power supply (yeah, I'm from Europe so we deal with 230v) this system should give me closer to 800w on ssb if my math ia right (yeah you can drive the 1000w inverter little over the spec for a short time) I'm going to build the filter for 10, 12 and 15m so the amp will never work down on the long bands.
I'm rocking a camper wan so I do have space to install the gear, having abaut 100A alternator and some extra battery capacity to not be a problem with current spikes
Excellent thanks David.
Excellent info, Dave, thanks!
Oh gosh Dave you are so FUNNY on this video! "The Lights Do Dim". Great point about the reflected power back from the antenna and feed line to the Tuner.... Thanks, Art
Hi Dave at about 19 min you mention that QST states a G90 and an amplifier will exceed spurious emissions I searched and could not find it on ARRL search, can you please site the exact article that you reference. I would also refer you to an Amplifier Build kit that I have built that will run on 115volts regular household power and produce 1.2KW. it is a KM3KM.
It's in the lab notes section. Last paragraph. March 2020 QST
I can't have an amplifier where I live, but I'd love one. Thanks for the clarity on amps. 73 W8XDX.
I can't have a ham radio amplifier for three reasons: One, amplifiers are _expensive;_ two, they typically need more current than what any of the circuits in my dwelling can supply; and three, you cannot use an amplifier in a portable station.
My reason for wanting more power is...I want to get through pileups and have stations I hear hear me. I have an ICOM 7300.
Often changing your audio settings will help there. Make your voice stand out.
@@madmagrider - Did that with Jimmy DOB out of NM. Next step is an Ameritron 811 600 or 800 watt, I only have a 120 watt outlet.
IS IT POSSABLE TO USE BATTERYS TO POWER YOUR AMP , CAUSE MY PLACE HAS OLD GLASS FUSES ??? THANKS. KB8WED
Dave,. Any thoughts on a sky wire antenna as described in the ARRL Antenna Book. It's cut for the lowest band possible, in my case 160, one full wave divided by four and put up in a square. Feed it with ladder line should work all the way up through 10 meters. Should have gain as you go up from 160. Can't do a vertical due to really rocky soil, tree roots everywhere, and can't do a tower. I want access to all bands including 60 and will be doing MARS again. Is there something better. W8PEF
I used to have a Skywire antenna, but it didn't work terribly well for me. I ended up taking it down and cutting it into radials for my vertical.
Would a 'star antenna D ' do mounted on a insulated base .
You have to have an amp if you want to work every night on 40, 80 and 160m. 40m international working Australia, Asia and Russia you have to run power and best around at least 1k. But if you want to only work the states and have hard times doing so with the lightening stay at 100w. 10m is about the only band an amp isn't much difference. Get a 572B amp for an instant on tube amp. Ceramic tubes you have to wait a minute or more for the tubes to warm up before transmitting without ruining the tubes.
I found an article in March 2020 QST on the G90. It says "we do not recommend using a power amplifier" how does this mean it will produce spurious emissions that will violate FCC Rules?
It stated in the lab notes that it doesn't meet FCC harmonic and spurious emission standards and phase noise is higher than they'd like to see. At QRP levels it probably doesn't cause too much problem. An amplifier makes it worse. If you input a dirty signal into a broad band amp, it's not going to get cleaner.
I'm surprised that in this discussion of power amps there was no mention of the inverse square law. Only minor mention of the rate of return by increasing power by a multiple of ten and by comparison of power increase seeing very minimal difference on the receiving end. Once we're all running a KW class station the next logical step is 5 or 10 KW. It's an interesting mindset regarding power amp.
If you want to put the inverse square law to the test start a QSO with 100 watts and ask for an RST. Then drop down to 10 watts and ask for one more RST without disclosing what change was made. I think it will surprise many.
73's
P.S. as you may have already guessed QRP Op here...
So what your saying is the dryer is going to the dump?
This was very helpful. Thank you for teaching this in such a practical way. 73, W0TJV
Hahah, I loved mentiong grabbing the DX contact during a contest. I indead have done that. :D
Hi Dave, 73's from the UK, I'm due to start the foundation course next month, about time 59yrs young!, anyway, as You probably know the 1st UK licence will limit Me to 10watts, My question is, Will that be enough power to communicate with the other side of the Planet?, I have no reason to reach further!, Or do I?, Keep up the great work Sir, Love Your videos, regards Stew.
This may be an odd question;
I'm fairly new in the HAM world, only got my license about a year ago, and I'm on social security...
Since HAM equipment is rather expensive (yes, even used...) I want to build a base station.
I am an electronics engineer, so that side of designing / building isn't really the issue, but what features should a reasonable entry level HAM transceiver station have?
And are there any good resources for design tips / feature tips etc. ? I mean, other than this channel of course :p Wouldn't ask anything here if I didn't find the information on this channel really informative and useful ;)
I don't know if it makes a difference; I'm in the Netherlands.
might want to look into the ubitx it's basically everything you need from a radio
IS IT POSSABLE TO USE BATTERYS TO RUN YOUR AMP ??? KB8WED ??
Great presentation of good information.
Lot of sense there Dave. Thanks😊
Great job Dave, I have just aquired a AL 811 H 800 watt amp. I have an HyGain AV-680 antenna but as you said you can't work them if you can hear them. A tower is not an option but even with what I think is a good antenna I don't hear very much DX. I bought the amp from a club member that is an engineer and got it at a great price. but think it will help with getting through to people I can hear but what about those that I can't hear. I live in South Dakota and have been told that because of my location hearing DX can be a problem. Is there anything elese I can do to improve my reception on my IC 7300?
Thanks, Jeff KE0KRO
Thanks for having the average Ham's best interest in mind. 73
I have an LDG-600 remote antenna tuner at my antenna. Do I place the amp between the radio and the tuner?
Will the tuner handle the power of the amp? It's only rated for 600 watts ssb.
@@loctite222ms I don’t have one yet but will only go with a 500 watt tuner.
@@w6bzy Do you mean a 500 watt amp?
@@loctite222ms yes, I type faster than my brain can keep up. Maybe the one David has. Limited space for one.
Yes, the amp goes right after the radio and before the tuner. Make sure the tuner can handle the higher power. Many do not.
Dave...what about old HeathKit amps like the SB200?
Yes, they work fine. If you are going to run on modern radio into the Heathkit amp, then you may wish to temporarily put it tuner between the rig and the amp to make sure that the to match. You can also use an antenna analyzer on the input to the antenna. You will likely be able to use the plate and tune controls to tune your antenna. Also watch out for how high the AGC voltage can get. Also check the voltage across the transmit input to the amplifier. This voltage must be grounded when the rig wants to transmit. If it's more than 5 V, and takes more than a few milliamps, you may want to put a relay in the circuit.
@@davecasler I plan on putting my antenna tuner in the loop between my transceiver like you suggested. I'm a veteran HAM on a budget, I have a Alinco DX SR8. Being new at HF after just getting my General rating. I would drop my radio down to it's lowest output power setting before using the amp...correct?
So what do you do when you hear stations and run 600 watts and they still can’t hear you
Dave Talk about the Dual BLF188XR 3,000 Watts 50Volts 160 meters -70cm
Thanks Dave and 73 de IWORZB
If you make contacts with contesters, you really should submit a 'check log' for those contacts. They are vitally important. Get a little, give a little. It's important.
Enjoyed this one👍👍👍
I think fewer people would get amps if they knew which antennas were better, but it's so complex they go for the gas pedal or go what I do and test every antenna under the sun.
Is a beam better then a vertical
Depends, they both have their own strengths and weaknesses. A beam will hear better and transmit better, in one direction. You will talk to different people with a vertical because of the radiation angle so the distance you get will be different. It is easier to get multiple bands on a vertical.
Yes in the direction that it is pointed.
And the audience agrees: MAYBE! Or is that sometimes? Vertical antennas have a low departure angle which is great for long distances. The big difference is polarization; beams are usually set up horizontal and want to talk only to horizontally polarized antennas of any kind. Verticals are, of course, vertically polarized (as are loops that are upright).
At higher frequencies the effectiveness of beam antennas is much improved and height above ground not quite as stringent. Over long distances that have bounced, polarization can rotate so the exact polarization isn't as important.
@@thomasmaughan4798 The polarization of the upright loop depends on where the feed point is. IIRC fed at the bottom it's horizontal. Fed on the side it's vertical.
Silly boy.
short answer is NOW....PS Bigger is better !
There has Been no better of a Time to Build your own Amp Solid State Then Now
Thanks David for another great show. All the other things not covered in the manual. KD9HWH,
Good show Dave, just get a better antenna is all you need.