Ever been told not to use RG58 or RG174? Well sometimes the advice is good, but sometimes it’s not! Connect with my channel by liking, subscribing and commenting.
Something that a lot of hams forget about, or just don't know, is that you need a balun loop (2wavelenghts) and tune the length to an even half wave length. This will more than compensate for any coax losses.
Fantastic! Absolutely fantastic! I do not use RG58 anymore, however I discontinued attending my local club when I was 16 due to the issues I had with other OM criticizing my use of RG58. At 16 years old I was really unable to afford any higher end coax. I had many of them telling me I NEEDED RG8x or LMR400. All of that is hogwash. You do not NEED it. Is it nice? Yes. However do not go around criticizing a hams use of coax. If you don’t agree, that is fine. But at age 16 and still in Highschool, I was unable to afford much more than that. I’ll also say this as well; DO NOT criticize a new hams use of 10 meters. In my first year, with my terrible coax as well as antenna setup (a 10 meter dipole strung up along the top of a privacy fence) I made well over 50 DX contacts in just the span of my summer break. I had many local hams shaming me because I was on 10. I stopped attending the club when I was 16 after 2 years of shaming for coax, antennas, and my interest in Boat anchors. And now if you look at my channel you can see just how far I have come.
My mate used RG58 because that is what he had, he ran it through his house out the the aerial and used it for ages. Then he got high quality coax from somewhere (it was supposed to be thee best) no idea of the number of it, but he had a hell of a job running it through the house, It was on 2mtrs. I gave him a help run it through, trust me, it was one hell of a struggle. Left him to it after it was in place, asked if it was any better he said "No, don't notice any difference, if anything it is worse, more noise!" I don't know about more noise, but I listened, and to be fair I didn't notice anything. He had quite a run of coax to a co-linear 2 mtr aerial. Both my mates used RG58 when mobile and didn't have any problems, yes there is maybe a loss, but they didn't notice anything! Neither did I to be honest. My other mate had fancy coax to his aerial on the house, but he was so high up it made little difference to him anyway!
Another good video, Thanks Tim! Since db, being logarithmic, is hard to grasp for most people I like to put things into real world perspective by framing loss in S-Units of signal lost, 1 S-Unit being 6 db. Therefore from your Chart for 7 meters of coax, the difference in RG-213 and RG-58 @ 10 meters is only .3db, or 1/20th of an S-Unit, and at 15, 20 and 40 meters its only .2 db or 1/30th of an S-Unit. IMHO that slight of a loss can't be noticed in real world operations, and many Hams take any losses at all too seriously. 73 mike
Great video, Tim. RG174 is great stuff for HF portable or SOTA. In fact, I just made a 2m flower pot antenna using RG174 and it works very well indeed. As you say, for short runs the losses are negligible. Of course others will have their own opinions but that's exactly what they are - opinions, not facts.
RG58 gets a bit of a bad press because there's a lot of cheaply made coax out there claimed to be RG58, and is sold cheaply on some E-bay sites, by some Amazon sellers and some CB shops. Get / pay for the proper quality RG58, and it's a good versatile and flexible coax. - You only get what you pay for, and perhaps there's a good reason why the coax you can buy on a bulk reel really cheap, is so cheap! Best myth I've ever heard about coax: Apparently many moons ago, in the days of AM CB, a guy in a CB shop was telling people that to get the best out or there radio, it was important to have their radio, coax and antenna set up properly, with the coax the correct way round. To install the coax the right way round, the writing on it had to read away from the radio and towards the antenna!
Great video Tim. You wouldn't believe how often I've been "bashed" for utilising RG58, RG174, even RG11 or ladder line as if I'm some mad fool. Hard to get around the salesman pitch though of, "RG213....because you're worth it!". Use whatever you like so long as it gets you on air and "don't sweat the small stuff".
Make sure you get the good stuff, and one cable run for each way of the signal, matching the arrows on the cable with the way electrons flow. :) The way this hobby runs is very similar to audiophiles. Fools and their monies are easily parted.
I just bought 15M of RG-316/PL-259 from Banggood for USD$15. I’ve been worrying that it will be a disaster for HF. According to the web, RG-316 is almost the same as RG-174 (better materials and temperature rating, same size). This video is the first that’s calming me that, once it arrives, it will be okay for field use (full-time living on my motorcycle). Thank you. I guess I’ll see now whether this cheap Banggood version is the real thing now. :)
I use RG58 portable because it's light and winds up well. Cheap to replace when damaged. At home I use Ultraflex 10 only because of the much better screening to reduce noise floor by 2 S points.
Hi Tim, thank you so much for this video. I'm using RG58 and RG174 from 80m to 2m and I do accept the small losses. If the antenna is well tuned (not by a tuner), it will equalize the loss of the cable totally. A well tuned ZS6BKW i.e. will work well with 10m of RG174. 73 Martin DG4BAD
Hi Tim, Great way to dispel those myths with actual figures. I had always thought of not using RG174, until I saw your figures. You and the family stay safe. 73 WJ3U
Well delivered As a seasoned RF tech, I can say that all the NMO antenna kits had RG-58 coax for 150, 460 and even 800MHz for years. It all worked for the EMS and land mobile crowd. As for RG-174, we refered to it as "Attenuax." Simply because most of the users were running it on frequencies 144MHz and up. Then again, these were the same ones using the antenna cut chart and calling it good.
Very helpful Tim Thanks. I just bought a Diamond X50 UV antenna from MOONRAKER. I was discussing it in our radio club UHF QSO on Monday evening and they all warned me to get the right coax . What they said is in harmony with what you show here in your charts. So I'm going to "stick it up" bolting it to my chimney and carefully measure the length, add a wee bit more, and go order it all made up. One experienced member mentioned something pertinent. He said that 1/2 of the importance of low loss coax is to transmit well. 1/2 is so you can hear a far away signal....
It’s funny because I was having trouble with my RG8 co-ax in the car so I swapped it out with 3m of LMR 400. I laughed when you said “jam it in.” I sure did.
Hi Tim I have been using 3 to 4 m runs of Rg174 on my magmounts and fixed mounts on my Landrover Freelander enabling me to feed so easily hidden the the vehicle and have found no difference compared to the original coax that was fitted to the magmounts. I also use it like you mentioned when out portable with the ic705 and end fed. Another good informative video Tim
I am dealing principally with operations on a variety of frequencies in the 136-174MHz range and RG58 is my goto solution for transceivers in a mobile/portable situation. That is mainly because its diameter and minimum bend radius makes it practical and less likely to suffer damage in those circumstance. Base stuff is wired in RG213 and has seriously good performance but that is possible because it is sitting undisturbed in wall and roof spaces and is laid out with nice large radii all the way to the antennae.
I’ve been using RG58 Mil on all HF antennae for decades. I use RG213 on V/UHF… never had issues and made contacts around the world. You now see RG174/316 used on HF these days with excellent performance.
Unless you're working very weak signals, none of these short coaxs would make a difference to your hearing. 1dB isn't even an S marker. Great video Tim!
Great video! I'm actually planning changing out all of my RG8X patch cables (due to intermittent connectors) over to RG58. The loss is about the same...pretty negligible. Also swapping out straight PL-259s for right angle connectors, which are easier to solder and takes the strain off the main pin. Sometimes, we need to challenge the status quo, yes? :) Thanks again!
LMR400 is not great for all applications, the aluminium foil/copper braid combination has been found to be a problem with passive intermodulation in some scenarios. Well done for your sensible analysis. In some situations cable loss is more critical, IE if you are a VHF DXer without a mast head pre-amplifier every dB of loss in the feeder will degrade your noise figure. Loss in RG58 gets far more ugly on 70cms and up, but it is worth a thought whether reducing loss would serve a useful purpose. 73 David
I worked in the two way radio field for 33 years and for mobile use, we always used RG-58 for VHF and UHF. EVERY major manufacturer of the mobile antenna kits include RG-58 cable runs. Only for 800 Mhz did we start providing the next size larger cable.
I have the same experience (general class - 50 years). -1db is a 20% loss. Which in most situations is transparent. A good antenna and transceiver will more than make up the difference. For long runs, higher bands, and high power, then RG-8U is needed. That said, I ran 450 Mhz with a 5 W handheld on RG-59 for several years using a home made dipole antenna as that was all I could get away with in my apartment. Worked just fine. Was it lossey? Yes. Did it really matter? No. I could still hit the repeaters a solid 5/9.
Coax loss works in receiving as well. Sometimes 1/2 or 1 dB can make a difference in getting that far far away QRP station or not. I've seen fellow HAMs use RG-213 in connecting their transceiver to the switches, SWR meters, low-pass filters etc. to get every mV into the transceiver...
I use RG-6 for transmission line on all my antennas. Reason why ?? It is what I have available. I used to work for DISH and DIRECT satellite TV, and when they abandoned us installers, I had several thousand feet of RG 6 in stock, some two cables and a drain wire. So, I had lots of transmission line, why buy another type of coax ? Despite 72 ohm being the natural feedpoint impedance of a dipole, the RG 6 is a match for that at 75 ohms, only three ohms difference. Now, the type of braid makes little difference, whether a coax has braided, or metal film based on plastic makes no difference because RF moves on the skin (skin effect). So it can be used on 160 meters through 70CM without loss. This fixation with 50 ohm cable to please your transceiver is practical, but excessive. What is the best transmission line to use, it is what you have on hand, or what you can get quickly. Granted, power levels determine what coax you use, but under 500 watts, RG6, RG8X, or whatever small diameter coax will do you fine ! I have even used 62 ohm Milsurp coax on 6 Meters with great success. You just have to tune the antenna accordingly. Cheap or readily available coax will always work no matter what the source is, just remember that lengths over 60' will get lossy no matter how good or expensive the coax is. Now, go out and experiment !!!
Ive been using 10ft of RG316 for a few months when out portable, I'd like to see a comparison to RG8X or 213 but so far it seems to perform adequately. Interesting stuff Tim.
I used rg8x for my 11 meter dipole antenna,works great I'm building a 10 meter vertical dipole antenna ,I'm gonna use rg8x for it also 🎉🎉 Cheers Happy Easter
Thanks Tim. Agree, portable ops, especially on foot, weight is key and the runs will always be short. At home, for a fixed install, then don’t skimp I say. Are Tim’s dry-clean trousers going to be a permanent feature from now on? 👖 Sheep kicked into touch (or hot pot)?! 🐑 🥘 😁
Coax loss in Db is just one part of the link budget. When added to a path loss of 100-200 Db, it helps but not often why the contact failed. Other factors aside, every time you double the distance the signal is reduced by 4 or six Db.
Looks like you've already been beaten to death about your 2 meter/RG58 myth use, so I've leave that horse alone.🙂 Great channel. I've learned several things from you. Thank you.
Hi Tim, good and interesting as usual, If you are going to spend all that money on radio gear and the sundries, why spoil your shack using cheap coax, ie RG58 always buy the best you can, anyway at the end of the day, as uncle Albert says "do as you bloody well like" lol. I love all these different views it makes a good talking point. good luck Tom. Thanks again.
Hi Tim. Well put & I'm inclined to agree with you. I'm not a big fan of RG-58. I have previously slated it in a couple of my videos. To be fair I did also say that RG-58 has it's place in mobile & portable setups. I use RG-58 for portable (SOTA & WWFF) & also mobile operations on both HF & VHF. As you correctly point out, I wouldn't use RG-58 in a fixed (home base station) setup.......at least not on VHF. Even on HF I would probably be looking at something slightly more heavy duty (RG-213 or similar) if I was going to go to the trouble of installing a new coax run. I know a lot of people do use RG-174 for SOTA. I personally don't. I've found it to be a little fragile compared to RG-58. Each to their own I guess.
Other coaxial myth is "multiple 1/2 lambda" length. Real context is very rare, bad tuned antenas preffer multiple 1/2. Second argument: impossible to cut "multiple 1/2" for wide range.
Thank you. I have used RG 58. It works fine. Whether on 2M or HF, the biggest problem is interference and atmospherics. Where you locate your rig, transmission line and antenna is much more critical, especially in reception. For my friends who are seriously competitive contestors, yes it appears to make a difference. NOQFT
Nice to see these figures here. I have 20' of RG58 to my h/b 4 element collinear and could probably cut it to around 8' as my collinear is right outside the window, and almost horizontal as I never got round to putting it vertical. I must get some pvc water pipe to run it inside and put it vertical. One day! I need to get a Round Tuit. About 45' of RG58 on my outdoor 60m inverted vee and about 25' to my 20m and 17m loft dipoles. Need to get the 15, 12 and 10m dipoles up now the bands are waking up. G4GHB
I am wondering because I don't know. 1dB isn't much but under the 2 following situations does it still not matter? 1) you have a good deal of distance between you and your contact and are trying to get as much antenna gain as possible. Obviously moving your antenna up will help but that means more coax. 2) you are running a low powered rig (5 watts) and are trying to maximize the reach of your signal. Again up helps but at the cost of more coax.
Great analysis Tim. It is a game of choices. There is no doubt that (decent quality not eBay rubbish) RG58 "works". It is all down to the marginal gains (excuse the pun!), that you have control over. Frequency, power and length of run are all factors here as you say. Once you begin to analyse these things, shaving off dBs may become obsessive - particularly if portable or QRP as you demonstrate. However if I have shelled out 1500 quid for a radio and spent hours (days) on my antennas, then I am not conecting them up with RG58, period. For the average mobile 100W radio - RG58 is fine. For any keen enthusuiast's home set up with investment and a yearning to maximise efficiency at a relative low cost - good (better) coax is the right choice. We can't all have Yagis and linears - but we can all have good coax for the price of a few Costa coffees.
One of the best improvements most amateurs could make is to learn to fit coax plugs properly Now for a proper roasting, point out the tiny differences in *measured* performance between PL-259 and N type connectors :) And yeah, I did wonder how you'd managed to make loss non linear
I've seen measured losses for various connectors and converters being around 0.01dB so I'd have to stack a load of them to notice a real-life difference. Mine are BNC as much as possible because they are more reliable and easier to deal with for portable - so many cycles of attach & detach...
What I find MOST surprising is how many operators will buy the BIGGEST BADDEST antenna on the market, and a 1Kw Linear and then run some old shitty RG-213 or similar coax they found in the back of the cupboard under a few dead mice, and then wonder WHY their mate with a cheap as chips antenna gets out better than they do, with his new clean RG-58 coax. Even RG-58 works if you set your station up well in the first place. I use a 60ft length of RG-58 into a homemade copper j-pole and I can open 144mhz repeaters 50klm away with 800mW output from my Baofeng UV82L. It's seems to work OK for me....opens the local 440mhz one's aswell on the same j-pole....gotta love those harmonics. 440mhz patterns might be all over the shop, but both bands are 1:1 SWR.
I think if you look more at 70cm and a more typical home rig where you might be using 20m of coax, you could be looking at 6-7dB loss (depending on which RG58 you pi ck) vs. 1.9 for LMR400. 4-5dB alone may not sound significant, but it isn't a vacuum. You need to look at your signal to noise ratio. 4dB can make a big difference. Most pre-made antenna setups run around 6m of coax, giving a 2dB of loss. (37% power loss). going a a well trimmed 4m of Ultraflex7 (between 213 and lmr400) you are looking at about .5dB RG58 is fine for jumpers, but for a VHF/UHF setup, you are better off with a well trimmed run of 213/LMR400.
Hi Tim, hope your well. Good video again. This might shock you, but I've got no idea what coax iam using hi, I cannot afford to be too picky so iam using a length of coax I was given on 80m through 6m, not sure of the length or losses but I know along with my home brew vertical ant, I get into eu from zl most evenings on cw and ssb. Maybe I should be worried and checking your calculations, but My old dad said, if it works lad, leave it alone hi hi. Get on the air and give it a go with what you have at hand I reckon. 10 years and it's all working well so far hi. Best wishes Tim, keep up the good work. Zl3xdj
100% Tim. People get their nickers in a twist over coax. I've long since made peace with it and have no issue using RG58, RG316 and RG8 for short runs.
Going off on a tangent (hope that's okay), coax losses come in to play at VHF UHF. My observation is most (all) stations use coax at VHF UHF. I've never seen open wire feedline used at VHF UHF. Is there a reason(s) why coax is preferred over open wire? I'm assuming open wire has the advantage of less loss at these higher frequencies so what's the trade off that makes coax the preferred feedline? Thanks for any thoughts/comments.
Also watch the braid on coax. I bought some RG58 at a rally years ago and got it home and was disappointed because the braid was very open weave. Maybe okay at h.f. but I wouldn't like to use it at 2m. I think I used it on my 60m inverted vee. I want to see the braid now before I buy any more. G4GHB.
Interesting video. I started primarily using RG-8X for portable. Since I am mostly QRP tough for parks whete I am operating from or near the car I typically use LMR-240UF these days. I do carry RG-174 in my KX2 pack. I don't disagree with what you saying but 1db of loss can be significant when only running 5 watts so I try to avoid the loss when I can. 73 de KJ5T
There is a use case for any type of cable. I look for the 1.5db point and if that is with in the length of run I need, any more than that amount of loss and I look at the next larger cable size. At the end of the day there is no wrong choice really as long as it meets your philosophy of use.
i would like to see someone make a homebrew 2m/70cm plantpot antenna out of 213, would need a tube as big as a dustbin to wind the coil round, and if its Mike MoMSN him rolling round the kitchen fighting with it. Rg58 cannot be that lossy seeing Mike use's it on most off his seff builds. Another great vid Tim. Aka NOT the timmy tool time Tim 😆73's M7RLL
G5TM Tim, Been messing about wid coax since first ticket in 62 so didn't expect to learn much but you pleasantly surprised me. Jolly good show but why is your steering wheel on the wrong side?---73 W8IMP JD LAS CRUCES NM USA AR K
I tend to use RG8 mini for everything. Somewhere between RG58 and RG213 for losses (a little closer to RG58 if I recall), but its lightweight and manageable. A good compromise I think. At this point in my Ham hobby/life, the small loss differences are not the most important thing to me. If I got deep into satellite and serious QRP, then I might consider the 'proper' stuff.
Good vid, thank you for putting it together. There's absolutely no shame in using RG58 for under 100 foot runs...you'll lose far more signal strength ( Rx and Tx ) to good old Gaussian distribution....8dB of normal signal fade in the UHF bands makes 3dB in cable performance differences downright trivial. No need to sweat over a couple dB.
@@timg5tm941 I threw up some satellite TV coax (RG6?) on my home made 5 element 2m/70cm quad just to try it as it was what I had in the house, expecting to replace it later. Funny thing, it seems to work very well, even with a reasonably long run I'm still getting into 70cm repeaters 50-60 miles away from the bottom of a valley with my antenna in the attic.
All engineering is about time, space (or weight) and money. We can set velocity factor aside, save for the calculations, so that takes care of time. So it's all about space (weight) and money. Roman Roads were labor intensive and used too much stone. But some of them are still around today. "Over Engineering" say with RG-213 might make sense if you can envision a high powered rig in your future, even if you are QRP now, since you've eliminated a weak link. Good Antenna comes first, but we use what we have on hand or can acquire and afford. That being said, I would like to see something on using 72 Ohm coax for the 50 Ohm radios if you have some of that lying around. And then there's the open wire, twin lead argument (and solution) that would also make for a good video. How to use what you have, even speaker wire or lamp cord or even a roll of mains wire for antennas/feedlines. You never know what situation you may be in, or what junk is actually in reality valuable surplus that can be used in a pinch. 73 DE W8LV BILL
Great points made here - I have loads of old twin core electrical cable I happily strip and use for my antennas. All are therefore brown and blue - could be my trademark! 73
@@timg5tm941 Before you strip it, try using it as 72 ohm twin lead feeder for a dipole, see how that does. I've used mains solid core electrical cable to wind all my un-uns/baluns.
The advice is; Use good quality coax, with good shielding. RG-174 can take about 197 watts on 50 MHz and nearly 150 watts on 2 metres. Even more on the lower bands. The problem with these coax cables is when using very long runs.
One of the subjects you're missing here is ERP. On 11m, many would run 20m or more of RG58 for their home base. Now if you have a high gain antenna, you could be missing out on a lot of potential performance. Many would see only 60-50% percent of the power reaching the antenna. Some are running a kilowatt or more! (I know it's highly illegal and abnormal, but this is a fact). So if you do the maths on a 6, 9 or say, 11.5db antenna, the effective radiated power figures go through the roof if you were to run half inch Heliax. Even when compared to RG213. Punch the figures into one of those loss calculators. And yes, I understand what this translates to an S meter, but why compromise if you have already invested so much, and remember it works on receive too.
The RG 174 is ideal for getting the feed into a car if you don't want to drill the body work as it will pass through the panel gaps and won't be crushed either. Ideal in short lengths. Negligible loss.
You certainly pick a topic full of misinformation. Like people have said theres coax then theres coax.. every situation will have its own specific needs if your trying to get that last dB of signal. What i have found over the years its not the coax its the issue its more the connectors and amount of connection points. Try and keep to a straight run and best connections you can, from there its your antenna, location and lastly coax. Luckily at HF wet string would nearly work. One reminder though is power power peak voltage vs coax flash over especially for HF. If RG58 doesnt foot the bill theres multitudes of others LMR195/LMR240 and upwards. I did have a giggle of using LMR400 in a mobile situation my want the ultraflex for that application! Anyway great video. Glad i found your channel
I use RG58 for mobile and SOTA 2m VHF and for in the car. If using the mast on rallies its RG213(but VHF low band) Home use its RG213 for HF and VHF/UHF
Personally, I think that there is no use for RG-58 as RG-X or LRM-240 are better and there is no significant cost or weight difference. RG-174 has it uses usually as short lengths (< 30cm) for use as strain relievers for HT attachment and to sneak coax through a car door or hatchback. The purpose of a transmitting antenna is to convert as much energy into radio waves as possible. A 3db loss means that half the power is lost in the Coax. For non-resonant antennas extra losses due higher SWR also have to be considered. My basic opinion is that coax should not limit the station performance. For an antenna with Z=200 ohms fed with 100 feet of RG 174 at 28 MHz the loss will be 7.9 dB for LMR 400 the loss will be 1.3dB.
Great info. I am running a cp22e+ 10m rg58 for my vhf reception. Does it have any factor with the reception coz i am able to receive only 3 local repeaters where a nearby Ham with same cp22e + rh213 is able to access almost all repeaters (10+) in 200 km radius.
@@timg5tm941 thank you so much... I made an upgrade today to lmr400 and increased the mast height to another 6 mtr and could see a considerable difference 🙏
Losses increase dramatically as wavelength decreases (1/lambda^1/2). Plot it up. The examples cited were for 2m wavelength for RG-58 and 10m for RG-174. Try rerunning these calcs for 70cm. Losses at 70cm are about 2x the losses for 2m and 4x for 10m. 70cm has greater range than 2m in urban environments. Our local volunteer emergency responders use 70cm ham and GMRS bands for emcomms for this reason.
the most important thing with vhf is height as we all know but with uhf there is a slight loss and they recommend n type fittings its basically up to the individual at home rg213 in the car rg58 thanks tim 73 m3hnl
Disagree Probably for 2M-FM, But for 2M-SSB i dont use less than LMR-400 for short jumpers, and LMR-600 or better for the rest. Remember dB's add up 1.2dB coax loss plus 0.5dB per-PL259 and a couple more on the SWR meter all of the sudden your at 3.2dB-3.5dB loss which is terrible! After many years of QRP, I've learned every dB matters and save losses where you can.
Maybe you can give me your .2 I’m getting into 10/11 meter running 1kw and my current coax is lmr400 but it’s just too difficult to work with for jumpers/patch cables. What’s my next best option ?
You will need really good coax to handle that power. I am unsure what is out there for you - look at the Messi and Paloni website for guidance on losses and power handling. Some outlets do bespoke coax lengths and plug fittings.
"right tool for the job", short runs, backpack carried, in vehicle, use thin stuff as you won't lose much, it doesn't weigh much and you really won't get RG213/LMR400 round the door seals of your car! at home, if you want 2 meters on a 7 to 10 meter tall mast, LMR400 all the way. on a personal note, i find RG58 awkward to fit to compression fit connectors. RG8x seems much easier to use.
I use RG213 at home for 2m/70cm, and purely because the RSGB recommends a coax of 'at least 10mm' for those frequencies.....my RG213 is 9mm, so I still have 1mm to find!?!
I think it's only a Matter of economics. If dubbeling the output power is more expensive than using better coaxkabel that will have 3 DB les los, the choice isn't All that difficult.
hi tim i go with rg58 and rg 174 runs under 5 m fore the longer runs usualy rg213 only vhen i run 25- 50 m radio to antenna usualy this hapens highy up in the mountains wher you cant deply antena and have at the base of the antena the radio not too muchy room so you need usualy other spots to deploy radio 73
I use 400 Max (aka LMR400) for everything other than portable, which I use LMR240 Ultraflex. Why? Because I can buy it in bulk and save money and in the case of my shack, I can put what ever antenna at what ever location I want. I bury my cables and have 4 different locations my antennas are at. As far as RG174, the vast majority of it is NOT suitable for use in adverse weather conditions. For POTA/SOTA sure, but to put it up in your back yard year round, no way. Also, there is the fact that it can't handle a lot of power (most of the time it is only rated at 72 watts @ 50MHz).
Very interesting thank you. I think that you're confusing columns with rows ie the Portable is the middle row not column. There is no middle column with 4 columns.
I think the biggest problem these days is finding good quality coax, I bought some rg58 off eBay and it was absolute rubbish the outer braid just fell apart as I was trying to fit a PL 259 to it so buyer beware
I got some of that! I bought it deliberately as the cheap stuff is copper coated aluminium which is very light, a lot lighter than copper. It's a bit more of a pain to work with and solder but I've found that it works very well for my portable setup of maybe 8 metres or so...and did I mention it's light? :-) For the decent (heavier!) stuff, go to one of the amateur radio stores, Martin Lynch or Waters and Stanton or the like. They have mail order/ebay sales as well I think.
I think it's down to what your happy with and you have to take into consideration, quality, price, weight & purpose ? I use RG58C/U Mil Spec for everything HF, UHF & VHF. I find it supple, good quality, good price, not too heavy and PL259's are cheaper using RG58 than larger diameter coaxes. I used to use any cheap RG58 back in my old CB days in the late 1970's, but now realise that any signal you do receive at your antenna isn't lost too much on the way down to the rig. Same with power going up to the antenna, especially if you are a Foundation licence holder where every watt counts. I think you should also consider the run length and have it as short as you can and check regularly the condition of your coax and connectors. Which is a must whatever coax you are using ? Sun, frost, wind and rain are the culprits for deteriation of coax, so check regularly and if suspect get new coax. If you value your receive and signal, I would change the coax every 5-10 years ? 73's Andy M6APJ.
So I heard that 3db is a 50% loss. Assuming that's true.(not sure it is) wouldn't every db matter. That means every tenth of a DB is 1.6 percent loss of power. 1 db of loss is about 16 percent. That's a big number. Sure it's just 1 db but percentage of loss matters. Thoughts?
Наука
***STOP PRESS: ERROR ON MY FIGURES! 10m RUN OF COAX ON 145 MHZ: RG58 IS 1.7dB, RG8X 1.4dB, RG213 0.9dB, LMR400 0.5dB.***
Very interesting video, thanks Tim
Something that a lot of hams forget about, or just don't know, is that you need a balun loop (2wavelenghts) and tune the length to an even half wave length. This will more than compensate for any coax losses.
@@welshbikepackingadventures thanks Mark
i got 3 reels of rg 58 for 30 bucks and us hams are tearing me new one for using it
@@don9100 almost 100% correct .. I was born and bred 15 miles west of Swansea
Fantastic! Absolutely fantastic! I do not use RG58 anymore, however I discontinued attending my local club when I was 16 due to the issues I had with other OM criticizing my use of RG58. At 16 years old I was really unable to afford any higher end coax. I had many of them telling me I NEEDED RG8x or LMR400. All of that is hogwash. You do not NEED it. Is it nice? Yes. However do not go around criticizing a hams use of coax. If you don’t agree, that is fine. But at age 16 and still in Highschool, I was unable to afford much more than that. I’ll also say this as well; DO NOT criticize a new hams use of 10 meters. In my first year, with my terrible coax as well as antenna setup (a 10 meter dipole strung up along the top of a privacy fence) I made well over 50 DX contacts in just the span of my summer break. I had many local hams shaming me because I was on 10. I stopped attending the club when I was 16 after 2 years of shaming for coax, antennas, and my interest in Boat anchors. And now if you look at my channel you can see just how far I have come.
Totally agree 73
My mate used RG58 because that is what he had, he ran it through his house out the the aerial and used it for ages. Then he got high quality coax from somewhere (it was supposed to be thee best) no idea of the number of it, but he had a hell of a job running it through the house, It was on 2mtrs. I gave him a help run it through, trust me, it was one hell of a struggle. Left him to it after it was in place, asked if it was any better he said "No, don't notice any difference, if anything it is worse, more noise!" I don't know about more noise, but I listened, and to be fair I didn't notice anything. He had quite a run of coax to a co-linear 2 mtr aerial. Both my mates used RG58 when mobile and didn't have any problems, yes there is maybe a loss, but they didn't notice anything! Neither did I to be honest. My other mate had fancy coax to his aerial on the house, but he was so high up it made little difference to him anyway!
Another good video, Thanks Tim!
Since db, being logarithmic, is hard to grasp for most people I like to put things into real world perspective by framing loss in S-Units of signal lost, 1 S-Unit being 6 db. Therefore from your Chart for 7 meters of coax, the difference in RG-213 and RG-58 @ 10 meters is only .3db, or 1/20th of an S-Unit, and at 15, 20 and 40 meters its only .2 db or 1/30th of an S-Unit. IMHO that slight of a loss can't be noticed in real world operations, and many Hams take any losses at all too seriously. 73 mike
Thanks Mike, good info 73
Great video, Tim.
RG174 is great stuff for HF portable or SOTA. In fact, I just made a 2m flower pot antenna using RG174 and it works very well indeed. As you say, for short runs the losses are negligible. Of course others will have their own opinions but that's exactly what they are - opinions, not facts.
Agree fully Ronan 73
RG58 gets a bit of a bad press because there's a lot of cheaply made coax out there claimed to be RG58, and is sold cheaply on some E-bay sites, by some Amazon sellers and some CB shops. Get / pay for the proper quality RG58, and it's a good versatile and flexible coax. - You only get what you pay for, and perhaps there's a good reason why the coax you can buy on a bulk reel really cheap, is so cheap!
Best myth I've ever heard about coax: Apparently many moons ago, in the days of AM CB, a guy in a CB shop was telling people that to get the best out or there radio, it was important to have their radio, coax and antenna set up properly, with the coax the correct way round. To install the coax the right way round, the writing on it had to read away from the radio and towards the antenna!
Oh crikey!!!!!
It's all about length and frequencies. You are all right! Every coaxials have its own uses.
Thanks for sharing this with all of us
I agree and thank you!
Great video Tim.
You wouldn't believe how often I've been "bashed" for utilising RG58, RG174, even RG11 or ladder line as if I'm some mad fool. Hard to get around the salesman pitch though of, "RG213....because you're worth it!".
Use whatever you like so long as it gets you on air and "don't sweat the small stuff".
Make sure you get the good stuff, and one cable run for each way of the signal, matching the arrows on the cable with the way electrons flow. :)
The way this hobby runs is very similar to audiophiles. Fools and their monies are easily parted.
Agree Victor
I just bought 15M of RG-316/PL-259 from Banggood for USD$15. I’ve been worrying that it will be a disaster for HF. According to the web, RG-316 is almost the same as RG-174 (better materials and temperature rating, same size).
This video is the first that’s calming me that, once it arrives, it will be okay for field use (full-time living on my motorcycle). Thank you. I guess I’ll see now whether this cheap Banggood version is the real thing now. :)
I use RG58 portable because it's light and winds up well. Cheap to replace when damaged. At home I use Ultraflex 10 only because of the much better screening to reduce noise floor by 2 S points.
Good points
Hi Tim, thank you so much for this video. I'm using RG58 and RG174 from 80m to 2m and I do accept the small losses. If the antenna is well tuned (not by a tuner), it will equalize the loss of the cable totally. A well tuned ZS6BKW i.e. will work well with 10m of RG174.
73 Martin DG4BAD
Hi Tim,
Great way to dispel those myths with actual figures. I had always thought of not using RG174, until I saw your figures. You and the family stay safe. 73 WJ3U
Thank you Don. You take care also
Well delivered
As a seasoned RF tech, I can say that all the NMO antenna kits had RG-58 coax for 150, 460 and even 800MHz for years. It all worked for the EMS and land mobile crowd.
As for RG-174, we refered to it as "Attenuax." Simply because most of the users were running it on frequencies 144MHz and up. Then again, these were the same ones using the antenna cut chart and calling it good.
Cheers Tim very informative, didn’t know about RG 174. 👍😉
Thanks Theo!
Very helpful Tim
Thanks.
I just bought a Diamond X50 UV antenna from MOONRAKER.
I was discussing it in our radio club UHF QSO on Monday evening and they all warned me to get the right coax .
What they said is in harmony with what you show here in your charts.
So I'm going to "stick it up" bolting it to my chimney and carefully measure the length, add a wee bit more, and go order it all made up.
One experienced member mentioned something pertinent. He said that 1/2 of the importance of low loss coax is to transmit well. 1/2 is so you can hear a far away signal....
All good advice Peter - enjoy the new antenna.
It’s funny because I was having trouble with my RG8 co-ax in the car so I swapped it out with 3m of LMR 400.
I laughed when you said “jam it in.” I sure did.
Ha!!!!
Hi Tim I have been using 3 to 4 m runs of Rg174 on my magmounts and fixed mounts on my Landrover Freelander enabling me to feed so easily hidden the the vehicle and have found no difference compared to the original coax that was fitted to the magmounts. I also use it like you mentioned when out portable with the ic705 and end fed. Another good informative video Tim
Thanks for the info! 73
I am dealing principally with operations on a variety of frequencies in the 136-174MHz range and RG58 is my goto solution for transceivers in a mobile/portable situation. That is mainly because its diameter and minimum bend radius makes it practical and less likely to suffer damage in those circumstance. Base stuff is wired in RG213 and has seriously good performance but that is possible because it is sitting undisturbed in wall and roof spaces and is laid out with nice large radii all the way to the antennae.
Exactly .. great information and typical I think of many installations. Thank you
I’ve been using RG58 Mil on all HF antennae for decades. I use RG213 on V/UHF… never had issues and made contacts around the world. You now see RG174/316 used on HF these days with excellent performance.
Indeed Andre 73
Unless you're working very weak signals, none of these short coaxs would make a difference to your hearing. 1dB isn't even an S marker. Great video Tim!
Thank You Hakan 73
Great video! I'm actually planning changing out all of my RG8X patch cables (due to intermittent connectors) over to RG58. The loss is about the same...pretty negligible. Also swapping out straight PL-259s for right angle connectors, which are easier to solder and takes the strain off the main pin. Sometimes, we need to challenge the status quo, yes? :) Thanks again!
Thanks!
Thanks for sharing this video. Great information, food for thought.
73 Steve AA4SH
Cheers Steve 73
LMR400 is not great for all applications, the aluminium foil/copper braid combination has been found to be a problem with passive intermodulation in some scenarios. Well done for your sensible analysis. In some situations cable loss is more critical, IE if you are a VHF DXer without a mast head pre-amplifier every dB of loss in the feeder will degrade your noise figure.
Loss in RG58 gets far more ugly on 70cms and up, but it is worth a thought whether reducing loss would serve a useful purpose. 73 David
I worked in the two way radio field for 33 years and for mobile use, we always used RG-58 for VHF and UHF. EVERY major manufacturer of the mobile antenna kits include RG-58 cable runs. Only for 800 Mhz did we start providing the next size larger cable.
I have the same experience (general class - 50 years). -1db is a 20% loss. Which in most situations is transparent. A good antenna and transceiver will more than make up the difference. For long runs, higher bands, and high power, then RG-8U is needed. That said, I ran 450 Mhz with a 5 W handheld on RG-59 for several years using a home made dipole antenna as that was all I could get away with in my apartment. Worked just fine. Was it lossey? Yes. Did it really matter? No. I could still hit the repeaters a solid 5/9.
Agree
Interesting
Coax loss works in receiving as well. Sometimes 1/2 or 1 dB can make a difference in getting that far far away QRP station or not. I've seen fellow HAMs use RG-213 in connecting their transceiver to the switches, SWR meters, low-pass filters etc. to get every mV into the transceiver...
Yep I agree in some cases
Ive broken every coax rule in the book and still made contacts and had fun.
Absolutely 👍
I use RG-6 for transmission line on all my antennas. Reason why ?? It is what I have available. I used to work for DISH and DIRECT satellite TV, and when they abandoned us installers, I had several thousand feet of RG 6 in stock, some two cables and a drain wire. So, I had lots of transmission line, why buy another type of coax ? Despite 72 ohm being the natural feedpoint impedance of a dipole, the RG 6 is a match for that at 75 ohms, only three ohms difference. Now, the type of braid makes little difference, whether a coax has braided, or metal film based on plastic makes no difference because RF moves on the skin (skin effect). So it can be used on 160 meters through 70CM without loss. This fixation with 50 ohm cable to please your transceiver is practical, but excessive. What is the best transmission line to use, it is what you have on hand, or what you can get quickly. Granted, power levels determine what coax you use, but under 500 watts, RG6, RG8X, or whatever small diameter coax will do you fine ! I have even used 62 ohm Milsurp coax on 6 Meters with great success. You just have to tune the antenna accordingly. Cheap or readily available coax will always work no matter what the source is, just remember that lengths over 60' will get lossy no matter how good or expensive the coax is. Now, go out and experiment !!!
Would love to see a rg-316 in your comparison list. It's crazy cheap and some QRP guys swear by it. Thanks for putting this vid together.
Good idea
Ive been using 10ft of RG316 for a few months when out portable, I'd like to see a comparison to RG8X or 213 but so far it seems to perform adequately. Interesting stuff Tim.
Doubt you’d notice any real world difference with 10ft Lee
I used rg8x for my 11 meter dipole antenna,works great
I'm building a 10 meter vertical dipole antenna ,I'm gonna use rg8x for it also 🎉🎉
Cheers
Happy Easter
Real LMR 240 coax is what I use the most and big coax I like to use RG400
Thanks Tim. Agree, portable ops, especially on foot, weight is key and the runs will always be short. At home, for a fixed install, then don’t skimp I say.
Are Tim’s dry-clean trousers going to be a permanent feature from now on? 👖 Sheep kicked into touch (or hot pot)?! 🐑 🥘 😁
At home on the HF base station, I run 9913 from the station to the antenna.
Good video. KD8EFQ/73
Thanks!
Coax loss in Db is just one part of the link budget. When added to a path loss of 100-200 Db, it helps but not often why the contact failed. Other factors aside, every time you double the distance the signal is reduced by 4 or six Db.
Yep
Looks like you've already been beaten to death about your 2 meter/RG58 myth use, so I've leave that horse alone.🙂
Great channel. I've learned several things from you. Thank you.
Thank you!
X & Y variances are certainly important concerning coax. Capacitance and inductance☑️
Indeed
Hi Tim, good and interesting as usual, If you are going to spend all that money on radio gear and the sundries, why spoil your shack using cheap coax, ie RG58 always buy the best you can, anyway at the end of the day, as uncle Albert says "do as you bloody well like" lol. I love all these different views it makes a good talking point. good luck Tom. Thanks again.
Agree 100% Brian
I use string, very cheap and plentiful.
Good short video. It makes you realize there isn't a big difference really in using thinner coax mobile or portable.
Indeed!
Hi Tim. Well put & I'm inclined to agree with you.
I'm not a big fan of RG-58. I have previously slated it in a couple of my videos. To be fair I did also say that RG-58 has it's place in mobile & portable setups. I use RG-58 for portable (SOTA & WWFF) & also mobile operations on both HF & VHF.
As you correctly point out, I wouldn't use RG-58 in a fixed (home base station) setup.......at least not on VHF. Even on HF I would probably be looking at something slightly more heavy duty (RG-213 or similar) if I was going to go to the trouble of installing a new coax run.
I know a lot of people do use RG-174 for SOTA. I personally don't. I've found it to be a little fragile compared to RG-58.
Each to their own I guess.
Exactly James some good points there
Other coaxial myth is "multiple 1/2 lambda" length. Real context is very rare, bad tuned antenas preffer multiple 1/2. Second argument: impossible to cut "multiple 1/2" for wide range.
Thank you.
I have used RG 58. It works fine.
Whether on 2M or HF, the biggest problem is interference and atmospherics. Where you locate your rig,
transmission line and antenna is much more critical, especially in reception.
For my friends who are seriously competitive contestors, yes it appears to make a difference. NOQFT
Good points Glen
Nice to see these figures here.
I have 20' of RG58 to my h/b 4 element collinear and could probably cut it to around 8' as my collinear is right outside the window, and almost horizontal as I never got round to putting it vertical. I must get some pvc water pipe to run it inside and put it vertical. One day! I need to get a Round Tuit.
About 45' of RG58 on my outdoor 60m inverted vee and about 25' to my 20m and 17m loft dipoles. Need to get the 15, 12 and 10m dipoles up now the bands are waking up.
G4GHB
Thanks Bill 73
I am wondering because I don't know. 1dB isn't much but under the 2 following situations does it still not matter? 1) you have a good deal of distance between you and your contact and are trying to get as much antenna gain as possible. Obviously moving your antenna up will help but that means more coax.
2) you are running a low powered rig (5 watts) and are trying to maximize the reach of your signal. Again up helps but at the cost of more coax.
Great analysis Tim. It is a game of choices. There is no doubt that (decent quality not eBay rubbish) RG58 "works". It is all down to the marginal gains (excuse the pun!), that you have control over. Frequency, power and length of run are all factors here as you say. Once you begin to analyse these things, shaving off dBs may become obsessive - particularly if portable or QRP as you demonstrate. However if I have shelled out 1500 quid for a radio and spent hours (days) on my antennas, then I am not conecting them up with RG58, period. For the average mobile 100W radio - RG58 is fine. For any keen enthusuiast's home set up with investment and a yearning to maximise efficiency at a relative low cost - good (better) coax is the right choice. We can't all have Yagis and linears - but we can all have good coax for the price of a few Costa coffees.
Nice points Tom. All swings and roundabouts. Mind you if 10m opens like it did last night then a dB here and there won’t matter a bean! 73
One of the best improvements most amateurs could make is to learn to fit coax plugs properly
Now for a proper roasting, point out the tiny differences in *measured* performance between PL-259 and N type connectors :)
And yeah, I did wonder how you'd managed to make loss non linear
I've seen measured losses for various connectors and converters being around 0.01dB so I'd have to stack a load of them to notice a real-life difference. Mine are BNC as much as possible because they are more reliable and easier to deal with for portable - so many cycles of attach & detach...
What I find MOST surprising is how many operators will buy the BIGGEST BADDEST antenna on the market, and a 1Kw Linear and then run some old shitty RG-213 or similar coax they found in the back of the cupboard under a few dead mice, and then wonder WHY their mate with a cheap as chips antenna gets out better than they do, with his new clean RG-58 coax. Even RG-58 works if you set your station up well in the first place. I use a 60ft length of RG-58 into a homemade copper j-pole and I can open 144mhz repeaters 50klm away with 800mW output from my Baofeng UV82L. It's seems to work OK for me....opens the local 440mhz one's aswell on the same j-pole....gotta love those harmonics. 440mhz patterns might be all over the shop, but both bands are 1:1 SWR.
Good info
Good and fair assessment, Tim. Thanks! de NY3Z
Thanks!
Excellent
Thank you Kenneth 73
For short runs it's certainly negligible. Greats points.
Agree - thanks!
I think if you look more at 70cm and a more typical home rig where you might be using 20m of coax, you could be looking at 6-7dB loss (depending on which RG58 you pi ck) vs. 1.9 for LMR400. 4-5dB alone may not sound significant, but it isn't a vacuum. You need to look at your signal to noise ratio. 4dB can make a big difference.
Most pre-made antenna setups run around 6m of coax, giving a 2dB of loss. (37% power loss).
going a a well trimmed 4m of Ultraflex7 (between 213 and lmr400) you are looking at about .5dB
RG58 is fine for jumpers, but for a VHF/UHF setup, you are better off with a well trimmed run of 213/LMR400.
Thanks for the info 73
Hi Tim, hope your well. Good video again. This might shock you, but I've got no idea what coax iam using hi, I cannot afford to be too picky so iam using a length of coax I was given on 80m through 6m, not sure of the length or losses but I know along with my home brew vertical ant, I get into eu from zl most evenings on cw and ssb.
Maybe I should be worried and checking your calculations, but
My old dad said, if it works lad, leave it alone hi hi. Get on the air and give it a go with what you have at hand I reckon. 10 years and it's all working well so far hi.
Best wishes Tim, keep up the good work. Zl3xdj
It gets you on the air - thats what matters Brian 73
100% Tim. People get their nickers in a twist over coax. I've long since made peace with it and have no issue using RG58, RG316 and RG8 for short runs.
Totally agree Colin
Going off on a tangent (hope that's okay), coax losses come in to play at VHF UHF. My observation is most (all) stations use coax at VHF UHF. I've never seen open wire feedline used at VHF UHF. Is there a reason(s) why coax is preferred over open wire? I'm assuming open wire has the advantage of less loss at these higher frequencies so what's the trade off that makes coax the preferred feedline? Thanks for any thoughts/comments.
Interesting point - sheer convenience?
Also watch the braid on coax. I bought some RG58 at a rally years ago and got it home and was disappointed because the braid was very open weave. Maybe okay at h.f. but I wouldn't like to use it at 2m. I think I used it on my 60m inverted vee.
I want to see the braid now before I buy any more.
G4GHB.
Good points Bill
Interesting video. I started primarily using RG-8X for portable. Since I am mostly QRP tough for parks whete I am operating from or near the car I typically use LMR-240UF these days. I do carry RG-174 in my KX2 pack. I don't disagree with what you saying but 1db of loss can be significant when only running 5 watts so I try to avoid the loss when I can.
73 de KJ5T
Fair points - QRP is more critical for sure
There is a use case for any type of cable. I look for the 1.5db point and if that is with in the length of run I need, any more than that amount of loss and I look at the next larger cable size. At the end of the day there is no wrong choice really as long as it meets your philosophy of use.
Good point about the 1,5dB and I share that same outlook 73
I'm using 10m RG8X on VHF/UHF and RG58 low loss on HF, low loss is the type with foil next to braid! how does that type compare?
i would like to see someone make a homebrew 2m/70cm plantpot antenna out of 213, would need a tube as big as a dustbin to wind the coil round, and if its Mike MoMSN him rolling round the kitchen fighting with it. Rg58 cannot be that lossy seeing Mike use's it on most off his seff builds. Another great vid Tim. Aka NOT the timmy tool time Tim 😆73's M7RLL
Thanks Richard!
G5TM Tim,
Been messing about wid coax since first ticket in 62 so didn't expect to learn much but you pleasantly surprised me. Jolly good show but why is your steering wheel on the wrong side?---73 W8IMP JD LAS CRUCES NM USA AR K
Ha! I never spotted that. 73
I tend to use RG8 mini for everything. Somewhere between RG58 and RG213 for losses (a little closer to RG58 if I recall), but its lightweight and manageable. A good compromise I think. At this point in my Ham hobby/life, the small loss differences are not the most important thing to me. If I got deep into satellite and serious QRP, then I might consider the 'proper' stuff.
Good points
you buy the best coax you can, well if you think of all the money you spent on radios and all the sundries, you should.
Good vid, thank you for putting it together. There's absolutely no shame in using RG58 for under 100 foot runs...you'll lose far more signal strength ( Rx and Tx ) to good old Gaussian distribution....8dB of normal signal fade in the UHF bands makes 3dB in cable performance differences downright trivial. No need to sweat over a couple dB.
Totally agree
You should do a comparison on RG-8 and RG-6. I use RG-6 on all my base and short repeater runs.
Ok good suggestion
@@timg5tm941 I threw up some satellite TV coax (RG6?) on my home made 5 element 2m/70cm quad just to try it as it was what I had in the house, expecting to replace it later. Funny thing, it seems to work very well, even with a reasonably long run I'm still getting into 70cm repeaters 50-60 miles away from the bottom of a valley with my antenna in the attic.
All engineering is about time, space (or weight) and money. We can set velocity factor aside, save for the calculations, so that takes care of time. So it's all about space (weight) and money. Roman Roads were labor intensive and used too much stone. But some of them are still around today. "Over Engineering" say with RG-213 might make sense if you can envision a high powered rig in your future, even if you are QRP now, since you've eliminated a weak link. Good Antenna comes first, but we use what we have on hand or can acquire and afford. That being said, I would like to see something on using 72 Ohm coax for the 50 Ohm radios if you have some of that lying around. And then there's the open wire, twin lead argument (and solution) that would also make for a good video. How to use what you have, even speaker wire or lamp cord or even a roll of mains wire for antennas/feedlines. You never know what situation you may be in, or what junk is actually in reality valuable surplus that can be used in a pinch. 73 DE W8LV BILL
Great points made here - I have loads of old twin core electrical cable I happily strip and use for my antennas. All are therefore brown and blue - could be my trademark! 73
@@timg5tm941 Before you strip it, try using it as 72 ohm twin lead feeder for a dipole, see how that does. I've used mains solid core electrical cable to wind all my un-uns/baluns.
RG6 is a great cable and cheap. I use it routinely as others. little mismatch and not to much loss.
Thanks for sharing
What about RG174 on those micro magmounts for 2m/70cms? They are typically a 3m or a 5m run. Terrible loss or bearable?
HF - not an issue. UHF - not great.
The advice is; Use good quality coax, with good shielding. RG-174 can take about 197 watts on 50 MHz and nearly 150 watts on 2 metres. Even more on the lower bands. The problem with these coax cables is when using very long runs.
Indeed
One of the subjects you're missing here is ERP. On 11m, many would run 20m or more of RG58 for their home base. Now if you have a high gain antenna, you could be missing out on a lot of potential performance. Many would see only 60-50% percent of the power reaching the antenna. Some are running a kilowatt or more! (I know it's highly illegal and abnormal, but this is a fact). So if you do the maths on a 6, 9 or say, 11.5db antenna, the effective radiated power figures go through the roof if you were to run half inch Heliax. Even when compared to RG213. Punch the figures into one of those loss calculators. And yes, I understand what this translates to an S meter, but why compromise if you have already invested so much, and remember it works on receive too.
The RG 174 is ideal for getting the feed into a car if you don't want to drill the body work as it will pass through the panel gaps and won't be crushed either. Ideal in short lengths. Negligible loss.
Agree Peter
I use RG-58 in the same scenario and don't get it crushed in my car. I've found the best place to route it out of the back door though.
hi good evening. i want to learn rf cable testing analyzing. could you please suggest me the which is best course to learn
You mean coax losses? Google coax loss calculator - lots to choose from and all very useful
You certainly pick a topic full of misinformation. Like people have said theres coax then theres coax.. every situation will have its own specific needs if your trying to get that last dB of signal. What i have found over the years its not the coax its the issue its more the connectors and amount of connection points. Try and keep to a straight run and best connections you can, from there its your antenna, location and lastly coax. Luckily at HF wet string would nearly work. One reminder though is power power peak voltage vs coax flash over especially for HF. If RG58 doesnt foot the bill theres multitudes of others LMR195/LMR240 and upwards. I did have a giggle of using LMR400 in a mobile situation my want the ultraflex for that application! Anyway great video. Glad i found your channel
Thank you, Phil, for both your kind words and the great information. 73
Laymans translation, 1.5 dB is about 25%
I use RG58 for mobile and SOTA 2m VHF and for in the car. If using the mast on rallies its RG213(but VHF low band)
Home use its RG213 for HF and VHF/UHF
Good info thanks
Personally, I think that there is no use for RG-58 as RG-X or LRM-240 are better and there is no significant cost or weight difference. RG-174 has it uses usually as short lengths (< 30cm) for use as strain relievers for HT attachment and to sneak coax through a car door or hatchback. The purpose of a transmitting antenna is to convert as much energy into radio waves as possible. A 3db loss means that half the power is lost in the Coax. For non-resonant antennas extra losses due higher SWR also have to be considered. My basic opinion is that coax should not limit the station performance. For an antenna with Z=200 ohms fed with 100 feet of RG 174 at 28 MHz the loss will be 7.9 dB for LMR 400 the loss will be 1.3dB.
Great info. I am running a cp22e+ 10m rg58 for my vhf reception. Does it have any factor with the reception coz i am able to receive only 3 local repeaters where a nearby Ham with same cp22e + rh213 is able to access almost all repeaters (10+) in 200 km radius.
Hi there. Yes it will be poorer than the thicker coax at vhf (I presume you mean 2m band). It also depends on the quality of the coax too.
@@timg5tm941 thank you so much... I made an upgrade today to lmr400 and increased the mast height to another 6 mtr and could see a considerable difference 🙏
@@HarishKottayam I’m sure it will
75 ohm squad reporting in.
Noted!
I thought of using 75 Ω on h/b tcvr but other gear is 50 Ω so went with 50.
G4GHB
Losses increase dramatically as wavelength decreases (1/lambda^1/2). Plot it up. The examples cited were for 2m wavelength for RG-58 and 10m for RG-174. Try rerunning these calcs for 70cm. Losses at 70cm are about 2x the losses for 2m and 4x for 10m. 70cm has greater range than 2m in urban environments. Our local volunteer emergency responders use 70cm ham and GMRS bands for emcomms for this reason.
Sure but I have no real interest in UHF
hello, can you tell me what is a good cable to use on the "HELIUM PEOPLES NETWORK" it is 1watt of power going in and it is 915 Mhz
hmmmmm...
hi i have 1to 1 at ground lever on rg58 but at 12ft up mast its 1.5 on 19 meter
the most important thing with vhf is height as we all know but with uhf there is a slight loss and they recommend n type fittings its basically up to the individual at home rg213 in the car rg58 thanks tim 73 m3hnl
Agree with you. 73
Then what would be best between a 5 watt handheld 2m/70cm and say a J pole 5m away?
Very interesting stuff
If you are up a hill and need a lightweight pack then for 5m use rg58. The j pole should be resonant or close.
@@timg5tm941 thanks Tim
Disagree
Probably for 2M-FM,
But for 2M-SSB i dont use less than LMR-400 for short jumpers, and LMR-600 or better for the rest.
Remember dB's add up 1.2dB coax loss plus 0.5dB per-PL259 and a couple more on the SWR meter all of the sudden your at 3.2dB-3.5dB loss which is terrible!
After many years of QRP, I've learned every dB matters and save losses where you can.
Maybe you can give me your .2 I’m getting into 10/11 meter running 1kw and my current coax is lmr400 but it’s just too difficult to work with for jumpers/patch cables. What’s my next best option ?
You will need really good coax to handle that power. I am unsure what is out there for you - look at the Messi and Paloni website for guidance on losses and power handling. Some outlets do bespoke coax lengths and plug fittings.
"Many people think"... LMAO let me add "Many people are M O R O N S"... Keep up the good work
Thanks!
What is the power handling of them though?
Rg174, the thinnest of this bunch, 100 watts peak without a problem on a well matched antenna.
I just use Hyperflex 5 which is basically the same as RG-58 but has around half the loss.
Good point
I use RG58 on 2m and 70cm about 10M run. It's cheap and lightweight. I have a 100M of Ultraflex 10 in the shed. Only used it once.
Thanks for the info
Can I put 100w into 174?
Absolutely!
"right tool for the job", short runs, backpack carried, in vehicle, use thin stuff as you won't lose much, it doesn't weigh much and you really won't get RG213/LMR400 round the door seals of your car! at home, if you want 2 meters on a 7 to 10 meter tall mast, LMR400 all the way. on a personal note, i find RG58 awkward to fit to compression fit connectors. RG8x seems much easier to use.
Good points
I use RG213 at home for 2m/70cm, and purely because the RSGB recommends a coax of 'at least 10mm' for those frequencies.....my RG213 is 9mm, so I still have 1mm to find!?!
Wrap the coax COMPLETELY in 3 layers of electrical tape and you'll be 1mm thicker......
Nice!
Im sure it will work
RG58's shield braid isn't very efficient at blocking stray signals passing through it and can leak rf causing problems with electronics.
Depends on the quality
Depends on the quality
I just put a comment about some RG58 I bought at a rally, very open weave braid so I want to see that before I buy any more at a rally.
G4GHB
How many dB is equal to 1 S unit? I think it's 3dB = 1 S Unit?
It’s 6
I use RG 8 MINI X HF VHF UHF 10 and 15 Metre runs works OK for my set up other peoples performance may differ
Yes - its what works for the individual
I think it's only a Matter of economics. If dubbeling the output power is more expensive than using better coaxkabel that will have 3 DB les los, the choice isn't All that difficult.
Yep that’s logical
hi tim i go with rg58 and rg 174 runs under 5 m fore the longer runs usualy rg213 only vhen i run 25- 50 m radio to antenna usualy this hapens highy up in the mountains wher you cant deply antena and have at the base of the antena the radio not too muchy room so you need usualy other spots to deploy radio 73
Noted
I use 400 Max (aka LMR400) for everything other than portable, which I use LMR240 Ultraflex. Why? Because I can buy it in bulk and save money and in the case of my shack, I can put what ever antenna at what ever location I want. I bury my cables and have 4 different locations my antennas are at. As far as RG174, the vast majority of it is NOT suitable for use in adverse weather conditions. For POTA/SOTA sure, but to put it up in your back yard year round, no way. Also, there is the fact that it can't handle a lot of power (most of the time it is only rated at 72 watts @ 50MHz).
Good points - thanks
Very interesting thank you. I think that you're confusing columns with rows ie the Portable is the middle row not column. There is no middle column with 4 columns.
Probably! Lol
I think the biggest problem these days is finding good quality coax, I bought some rg58 off eBay and it was absolute rubbish the outer braid just fell apart as I was trying to fit a PL 259 to it so buyer beware
I got some of that! I bought it deliberately as the cheap stuff is copper coated aluminium which is very light, a lot lighter than copper. It's a bit more of a pain to work with and solder but I've found that it works very well for my portable setup of maybe 8 metres or so...and did I mention it's light? :-)
For the decent (heavier!) stuff, go to one of the amateur radio stores, Martin Lynch or Waters and Stanton or the like. They have mail order/ebay sales as well I think.
How about RG 136
I think it's down to what your happy with and you have to take into consideration, quality, price, weight & purpose ? I use RG58C/U Mil Spec for everything HF, UHF & VHF. I find it supple, good quality, good price, not too heavy and PL259's are cheaper using RG58 than larger diameter coaxes. I used to use any cheap RG58 back in my old CB days in the late 1970's, but now realise that any signal you do receive at your antenna isn't lost too much on the way down to the rig. Same with power going up to the antenna, especially if you are a Foundation licence holder where every watt counts. I think you should also consider the run length and have it as short as you can and check regularly the condition of your coax and connectors. Which is a must whatever coax you are using ? Sun, frost, wind and rain are the culprits for deteriation of coax, so check regularly and if suspect get new coax. If you value your receive and signal, I would change the coax every 5-10 years ? 73's Andy M6APJ.
Good points Andrew
The first myth is that LMR400 is the only good cable available.
Indeed
So I heard that 3db is a 50% loss. Assuming that's true.(not sure it is) wouldn't every db matter. That means every tenth of a DB is 1.6 percent loss of power. 1 db of loss is about 16 percent. That's a big number. Sure it's just 1 db but percentage of loss matters. Thoughts?
I compare it to s units. 6dB is a single s unit. 3dB is half an s unit. So overall 1-2dB isn’t a huge deal breaker from my perspective 73