Standing Inside a Broadcast Transmitter While it's ON!
HTML-код
- Опубликовано: 27 сен 2024
- See inside a Gates BC-250-GY broadcast transmitter from the 40's era. Lots of big Tubes, Transformers and Capacitors! Check out my Patreon site here: / mrcarlsonslab
Hey! Learn more about electronics, and see more of my video's on Patreon. Check it out here and join the crowd: www.patreon.com/MrCarlsonsLab
plz make tuning video thx bbz
Mr Carlson's Lab k
Hi mr Carlson.
Mr Carlson's Lab I need a 50,000 watt commercial am amplifier for use in CB band
Wow! I thought that was going to be a few kilowatts...
I’ve run pirate radio stations in the uk since 2000s and my 300wt fm transmitter is about the size of the grey box on top right of that am transmitter.
Once we turned a 150wt transmitter on indoors to see if it was what we’d paid for...
within 5-10 secs we started feeling a bit weird..
Felt a bit stunned and like a eiry feeling..
We only did that once..
assumed it was frying us like a microwave 🤣
In 1965 I was trained at ferris state college in transmitter service man does this bring back memories this was way before digital electronics, really enjoy all of your videos you do a super job from Brian WB8IDY in Michigan please beep up the good work 73
i was a army radio operator for the dutch army in 1998 just before they went digital , it was a single side band radio built into a shelter that was put onto a truck that i also happened to be the driver for . i don't really remember what set number it had in there but it was the coolest radio that i ever played with , we had different anteny with it like the straight 20 meter ( or so )pole , we could make a dipole antenna and a cartwheel antenna , that thing had a good deal of range also when using the signal booster that it was equipped with outside the rf protected cabin , man i tell ya when the booster kicked in ( and you had to give it a few seconds to get to full boost before broadcasting) that thing could fry some stuff , it was for that reason the warning no to get anywhere near the antenna when in use for so i was told it could fry an egg .
I remember seeing a huge machine about the size of a bus, that used 50,000 W R.F
to heat & dry toweling running through it. When you open any of the side doors, all
the lighting inside was just numerous Fluoro Tubes, held with spring clips !! No wires.
Just found your channel and enjoy your content very much. 30 years ago I was a Chief Engineer for an AM station that used the BC-1/T (1KW) and a BC-250/T as backup. One night after a huge storm, the roof failed right above the BC-1/T and flooded the cabinet. When I arrived, there was standing water on top of all of the transformers, reactors, capacitors. It was a mess. I removed everything that could soak up water, took those parts to a motor rebuilding shop that "cooked" the transformers, inductors, etc. at a low temperature for a few days. Everything checked out okay. I reinstalled, retuned everything, and the transmitter worked perfectly. Didn't have to buy any replacement parts. Gates had excellent well written manuals. Neat to see the BC-250/GY in this video!
You just took me back 50 odd years, serving in the RAAF starting in Jan 1972 I was posted to Butterworth Air Base, Malaysia. We had a radio broadcast transmitter and studio which collectively went by the callsign RRB, 1KW I believe. I didn't work on the AM broadcast band transmitters such as this but remember the large transmitter hall where it sat dwarfed by the huge HF transmitters we used for communications back to Australia from the base. A mate of mine from the ground radio side showed me the huge complex and antenna farm.
Now I was a radio tech air which meant I worked on airbourne radio comms , navigation and radar equipment. As it transpired I finished up working on the Mirage III Cyrano II fire control radar for 6 years (many pictures of the beast on the net). The RF final and modulator electron tubes you show are bigger than anything I worked on but there were huge water cooled electron tubes in some of the big HF TX's with PEP of several thousand watts. I had not ever seen tubes that big before, I was in my early twenties and had completed a 5 year electrical/electronic apprenticeship at 15 before I joined the RAAF.
I am retired from the RAAF now, spending my last serving years teaching electronics at the then RAAF School of Radio which sadly no longer exists.
Thermionic electron tube theory is fairly basic and easy to understand compared with our world of microprocessor controlled electronics now.
I obtained my amateur licence in 1989 only having to sit for regulations, the theory was waved. I am wondering what band you work with that transmitter as you would have to retune the drive, final and adjust the ant loading every time you changed your VFO frequency.
I am not active at the moment due to wide spread QRM at my current QTH. It's so bad I can't really receive anything except the two local AM broadcast stations and the NDB from RAAF base Sale, Victoria up the road where I had two tours , I am still investigating. Cheers Robert VK3URS
My wife says I have too much stuff but then she saw Paul's electronics lab. Now she just complains about other things lol.
You can never have too much
This took me back a ways. 60 years ago I received my 3rd Class Broadcast license. I was in high school and I worked at our local Radio and TV station in Ohio. It was a great experience
.
Feb 2021: My first impression of Mr Carlson's Lab with this video last year. Back for a replay.
Just gotta say thanks for lighting a well needed fire under my life-long but recently dormant interest in electronics. I've watched a dozen or more of your videos and am marveled at how you take the fangs off of some of the most intimidating repairs and restorations. It's been a welcomed and refreshing boost to my own electronics aplomb. Thanks Paul.
Great to read! You're Welcome.
I felt the same way.... I'm only a Gen Ham License, ... got bored until I found Mr. Carlson...he rocks Radio !!!
What a great presentation! Large transmitters have always fascinated me, especially The US Navy VLF xmitters such as the one that use to exist at Annapolis. I'm a past USN communications electrician and you've really sparked my enthusiasm for electronics again. Thank you for that Mr. Carlson.
Great! You're welcome Scott!
ETN?
When you spoke of the HV interlock switch I was reminded of Max Ferguson's story of the CBC Toronto Xmitter.
One of the non-technical staff would open up the door to heat his meal inside and cut off transmission every night. The engineers couldn't figure out why it was happening.
lol!
Very funny
kaybikerow Or in my case get some winter time heat by putting standby transmitter into the dummy load LOL!
My father designed parts of that unit and built many of them. He worked for Gates Radio Company in Quincy, IL for 35 years till they merged with Harris Intertype to becomes Harris Broadcast products. I used to walk inside those units as they were being built. He also designed towers and antennas.
Great story! Thanks for sharing.
Great video! A trip down memory lane for me...in the late 1960s, I worked for RCA in Meadowlands, PA, building AM broadcast transmitters...mostly 5kw units, in walk-in cabinets like your Gates. Lacing cables, bolting stuff in place, wiring them up. My initials are inside the cabinets of several XRs. As a young guy, it was exciting for me just to be around heavy iron like that! Something magical about big glowing tubes . . .
Thanks for taking the time to write!
Very cool . . . big tube transmitter! Appreciate the detail minutia of operating this beautifully restored piece of radio machinery, it is something of an artform. Have no idea why anyone would give a thumbs down. I remember in the distant days of my youth (a very long time ago) being fascinated with high power tube circuits . . . big transformers, big relays, big caps, big everything! I'm amazed there are engineers today who understand the subtleties of bringing this ancient radio tech to life and keeping the artform alive.
What a Great Teacher Mr Carslson is, he is Pleasant, Courteous and Brilliant in his Delivery
And he looks like he just pooped his pants.
Early 2020: Mr. Carlson and Jordan Petersen, top 2 on my list. :)
Brings back memories, when I was in Electronics class in High School 1965-1967, we had an old army transmitter. It was a bc810? We drove 300 watt light bulbs on the output and had a lot of fun with it.
MIGHTY good entertainment. I have absolutely no idea how this stuff works, or really any huge interest in the radio itself BUT I like watching you talk and explain all the stuff that you do.
Love your style and the deep understanding you have of electronics from before I was born to modern day technology.
Excellent presentation, Mr. C. I have always enjoyed seeing the guts of these older devices perhaps because I started my career in the the era (1960s) when you could walk inside computers even though they were solid state.
Would have never been able to have a tour around an old transmitter like that without this channel, interesting stuff thanks
*Saw the title and thought, If he says, "Don't try this at home," I am never coming back here again.* :o)
In Britain when the CB radio craze was just starting in the 1980s everyone was using illegal AM sets imported from America. It was legal to own them but not to use them to broadcast with. A law everyone and his granny was breaking.
I bought a Plymouth car at auction and in it was an AM CB radio. I had to buy a mag mount antenna for it and the very first time I switched it on was just before sun down on a Summers evening. I switched through each of the forty channels and heard nothing. Then suddenly I heard an American voice. In a few minutes I realised it was a taxi driver calling his controller. Feeling vaguely stupid I keyed the microphone and called out to the, "Guy in the taxi calling his boss" and asked if he could hear me. To my utter amazement he answered wanting to know who I was.
It was a moment of true wonder for me and I became hooked on radio as a result. Pretty soon after I bought a bigger and better rig called a "Ham International" and soon I was surfing the skip on lower side band and talking to people all over Europe. I called it radio fishing. My love for radio was born that day and has never left me. Not bad for a 4 watt transmitter.
That is a great story! I hope do be able to do that soon!
Great story
I'd imagine it must have been immense to hear some random guy on the other side of the world for the first time
Now with the internet it's so commonplace nobody bats an eye
Phones and internet are very good for worldwide comms, but it doesn't replace the magic of radio, kind or hard to explain but I'm going to try.
With the internet you just make a connection and thats it, the message gets through and you're done, however with radio, plugging an antenna into the back of a box, then fiddling around with a control until you hear something breaking through the static seemingly from thin air and in the case of the person above, keying up and replying finding out they're on the other side of the planet is pretty damn cool, especially if you build your own set.
Well said, that's exactly what I thought!
We Yanks were walking across the pedestrian bridges into Nogales or Villa Neuvo Mexico or any other town in Mexico and walking back with illegal linear amps, under our arms, for use on 11 meters, back when CB was super popular. The CB cowboys are still pushing as much as 100,000 watts, on 11 meters, and spreading their charm and wit, or should I say, witless charm, across the airways. So the CBers are still exceeding their legal limits by 40,ooo or 50,ooo Watts, and using all manner of profanities. They are a crusty bunch of characters. I missed the Hamfest in Scottsdale this year, and my mate from London. He found a lovely old ARC Pye mobile made in Cambridge. Imagine finding a London police two way VHF set in Arizona, and it even still had to mounting bracket! These CBers are supposed to be limited to 4 watts AM, or 12 Watts SSB, but they have no problems running 110dB over that. It's all rather silly, but I guess they enjoy each other's company. I have reached Florida QRP with 5 watts, from Phoenix Az. That's not too bad. I can run 1500 with my Amp Supply, or 1200AM, or 900 RTTY, and 1500 RTTY with me solid state rig, and 3000 SSB, but I keep it down to the legal limit, of 1500 Watts PEP.
What a great walk back in time! Reminds me of interesting thing that happened to me shortly after I started to work for WBT-AM in Charlotte NC 57 years ago! I was only 19 at the time but had been a ham since 11.
After being on the job for only two weeks, the chief engineer assigned me to start on the second shift SOLO! That scared me to death because I would have to switch directional that afternoon, and I had not had the opportunity to do that before! Now WBT-AM was a big deal - 50KW from that big ol' RCA BTA-50 spreading from Canada to Cuba blasted millions of ears - a point impressed very strongly on me by the CE. Anyway, the guys who I trained with on the first shift told me NEVER to switch on a modulation peak or it could take the transmitter down! Now the DJ at that time felt there should be no lapse of audio content between music - I never knew him to ""run out of gas."
Well, the time finally came to make the switch. Ty Boyd just would not stop talking! Five minutes after the official time to switch, I finally went for it! BANG! Huge plate breakers in the high voltage bay loudly signalled their displeasure at the current overload when the relays came back in directional mode. Then SILENCE! I almost messed my britches cuz all I could think of was that millions of people all over the world had lost their favorite station and I was the one to blame! I cud just see that pink slip coming! And I was planning on getting married in a couple weeks and cud see that going down the drain!
I deduced that the problem could be remedied by going into the transmitter entry bay and manually resetting the main high voltage breaker. Bad decision! When I reset that breaker the DJ was still talking and the same problem occurred - this time the primary AC breaker tripped and the whole transmitter went black! Not a tube was lit! Now the CE had been trying to maintain some sort of industry record by keeping the filaments on those big finals hot for the longest time since initial installation. I remembered him proudly telling me that those finals had not had their filaments turned off since they were installed several years prior. All that was running through my head and I had no idea how to get that transmitter back on the air without it shutting off again!
After what seemed like an eternity the phone rang. It was the CE. He calmly asked what happened to the WBT-AM signal. With a shaky voice I told him the situation. He had me turn off all the switches that had to do with power and cut the main audio switch. Then he slowly and methodically talked me into bringing everything back up in sequence starting with the primary AC breaker. Eventually, I got the transmitter back on the air and adjusted the various controls to get the directional RF power set to the proper level to drive the three towers.
After I convinced the CE I was OK and the transmitter was doing what it was supposed to, he hung up. I was just waiting for him to come in and fire me. In about 15 minutes I heard him come in the front door and go straight to his office. I was mentally preparing for him to tell me that was my last day as an engineer for WBT-AM! However, at my great surprise, being the tremendously professional he was, he came out and CONGRATULATED me for the excellent job I did in not panicking and getting his beloved station back on the air!
Needless to say, the lesson I learned was to cut the audio at the appointed time before switching directional, regardless of what the DJ was doing, whether talking, playing music or running a commercial!
That experience not only taught me a lot about broadcast transmitter operating procedures it built my self confidence and taught me a lot about managing and dealing with people. I went on to spend 47 years with that company, eventually rising to Vice President of IT for the entire company. When I retired, the company owned 3 TV stations, 17 radio stations and a sports production company.
Keep up the good work, Mr. Carlson! I just joined your world as a patreon! Thanks again for the enjoyable trek back in time and for the excellent job you are doing in educating both old and new about the the wonderful world of radio and electronics repair.
Joe AB4WF
Thanks for sharing that great story Joe, that was a very enjoyable read. Thanks for your kind comment too!
Thanks again for a interesting video.I did the A/C on these transmitter shacks and saw these Gates Transmitters, now I know what I was helping to cool down. Thanks again!
Beautiful! In the early 1980s, I had a transmitter across the street from me in Pennsylvania. WEEP, with a glorious 50kW RCA transmitter.
It has a beautiful four tower Marconi antenna array.
That evening, the engineer was working on the rig, changing an RCA 5671 output tube.
It is the largest tube I have ever seen. Large enough it has its own jack to lift it into position, the apparatus was impressive.
I had the pleasure of seeing the interior of this transmitter as a lad.
Every time you touched a component in there, made me pucker up.
You have D104's! I had one with a 6-wire cable back in the 70's. I ran a Surveyor 23 channel mobile through a salvaged Starduster antenna. I had great range and annoyed a lot of guys with full base stations. They had Browning and Cobra radios and I kept up with them. The D104 brings back great memories!
I just love the look of vac tubes, those two transmitter tubes would make awesome night lights lol. I just love the way they look. I grew up with tube tv's, not just the picture tube mind you. the kind of TV that would take a few minutes to warm up because the tubes were cold and needed to heat up. I would look in the back at the warm glow of the tubes in the back of the tv. I was more interested in what was IN the tv rather than was was ON the tv when I was a kid.
I guess tubes just hold a nostalgic memory to them.
Great video, nicely voiced.
Thanks Mike!
three years later and youtube brings me back here. this is the first Mr. Carlson video i ever saw after falling into a rabbit hole caused by cheap Chinese ham radios. i've been subscribed ever since. Thank you for teaching me so much about the world of electronics and radio through history, and thank Baofeng for sparking my interest in Ham radio.
Nothing like Gates transmitters and a Collins board along with Altec Lansing squirrel cage mic ! I started in 1972 and loved it 👍
As a young teen, I was friends with a lot of Ham operators. So I was exposed to a lot of radio equipment & towers, and repeaters.
Awsome transmitter, thank you for the tour.
Thank you for the succinct , crisp, enlightening information! A real pleasure to watch!
Thanks Chris!
As a ham radio operator, this was right up my street. Loved every minute. MM0SDK.
My late father was a big ham radio operator, loved to sit in the garage with him while he would see who was on the air, W4GTH
84 thumbs down so far. I guess they are from people who hate people who know what they are talking about, and think that "learning" is a bad word. Or maybe they're just jealous of your lab. (...who wouldn't?)
BDW, your videos are gold. I've been in the electronics field for around 25 years, and not only reminds me how much I still have to learn, also how much I have forgotten. Thank you very much Mr. Carlson.
chevylization Absolutely agree. I'll never going to understand the state of mind of the people that thumbs down a top quality video like this.
How to tell if your gs31 is bad
"The damned Earth is flat I tell you, flat! Knowledge? Logic? What is this fakery!?" OK, they are just knuckle-draggers, phew!
If your into radio / electronics, why would you thumbs down this ? Takes all kinds I guess.
Some of em are Swedish girls. Think of all the radiation this thing emits. There's probably asbestos inside.
Last time I saw a beautiful Gates box like this it was in my little station back in the 1970s when radio was still king.
Thank you for the nostalgic journey
I love these old amps, Please do more :)
Paul I love to see all your videos I learn something every time i watch.You are a very smart man I wish i knew just part of what you do thanks again and can't wait for your next one
When the robots rise in 20 years and the great A.I. war begins, If you survive you will be using this thing to broadcast the rebellion. Very cool! : P
When the great A.I. war begins I have a feeling he will be viewed as a superior intellect to them so he will be feared and untouchable... LOL
Or kept alive to repair them like some kinda techno noir egyptian priest : P
The ghost IN the machine....literally....
no.....
Moan....
I love to see history stay alive. Thanks for sharing that and keeping the old great stuff alive.
Awesome video! Thank you so much for taking the time to produce these.
Nice job! Good instructor, very detailed, very professional, very enjoyable to hear you explain the broadcast transmitter. NICE equipment too! Thanks so much. Jeff
We have one of those "shacks" with broadcast tower for CBS AM next to my house. Lot more than 250 watts. So much so anything with a diode, corroded connection, or just unsupported wires (like a toaster) will pick up and "play" the station just fine. Fortunately its mostly sports radio so I can get my update while my toast toasts.
Do you hear it in dental crowns? That'd be convenient! Hahaha
(Myth Busters did a segment on that once, it was interesting)
mysock351C l live behind an AM station and have for many years. I think it's around 25,000 watts daytime. We used to hear it on all our landline phones and on certain TV channels. Basically anything that could act as a receiver would tune it in just fine. Hell, I remember using my tone and probe set to trace some wires in my house and the probe was picking up the station the whole time! They did a mod and upgrade to the station some 20 years ago and that mostly eliminated the Interference.
I used to get the local religious station on the landline phone. Hard to talk to people when there is a voice yelling "praise jesus" the entire time.
You remind me of when I lived near my local fire station and occasionally I would pick up the VHF chatter on my audio amp whilst listening to some music. When I thought about it more, I realsed that a pre-amp is basically a radio reciever, just wired a little bit different.
With 200 watts or more of RF tx, as you say, it will modulate to anything that's got a diode and a coil in it.
That is because your landline telephone had wires connecting it to the wall! If the wires are the length of some even--fraction of the frequency the signal is being broadcasted on, the telephone wire acts as a "receiving" antennae! The signal is then amplified by your telephone. You can either switch to a "wireless" hand held telephone because they have excellent signal rejection qualities---or you can buy several iron toroidal coils, and wrap your telephone wire from the wall around the iron form several times. Do this maybe three times with the coils spaced out a couple feet! The iron cores absorb the extra signals.
Paul, Thanks for the tour! Was a really great look into a fascinating piece of history.
To amplitude modulate a 250W transmitter, you need at least 125W of audio power which accounts for the large audio amplifier and modulation transformer down there on the floor.
A radio DJ for 17 years I have an affinity for old broadcast transmitters. This video was wonderful to view, thank you! I would enjoy more of these as well as seeing how you tune these. w0xs
Beautiful technology, excellent channel, flawless presentation. Thanks a million Mr. Carlson.
I interned at a small AM station that had one of these hooked to a telephone based remote control. You'd hit the right keys on the phone and it would announce, "Plates are ON!!!" So cool... :)
(24:42) - I like the way Paul says *_"Audioble"_* for *_"Audible."_*
It somehow conveys more meaning, though what exactly, I'm not too sure.
*_Go Mr Carlson !_*
>
Audible is just something you can hear. Audioble is something you can hear, then stroke your beard, nod, and go "hm..."
Well done, another fascinating video. There is something rather special about comparatively simple but large equipment that you can can actually maintain.
In my hometown there was an AM broadcast station that _'forgot'_ to switch to night time power on one night. They were heard very clearly in Venezuela ... from North Carolina.
Sean Watts AM dxing still sometimes produces some odd results. I've caught some from Mexico and I'm closer to where your cranked up country station was
The opposite happens all the time. At night, I used to always get as many mexican stations as american... in tennessee. I say mexican, but honestly, I don't really know if they were speaking Spanish or Portuguese, so some of it may have been south america.
When I used to dx AM stations at nite in northern Indiana, very quickly I found that conditions were such that you either had good Canadian reception OR good reception of Mexican stations. Never both. But those (much!) higher-powered Mexican outlets were alot further away!
I've managed to pull in a fire & brimstone preacher, from Florida I believe, in North Wales one evening. that's about the extent of my DX'ing though lol. I recently acquired an old Sharp music centre though that seems to have a particularly hot tuner so might set up some antenna and see what it brings.
Good of you to take the time to share with us. Please keep going.
Thanks a mil! looking forward to watch the next ones!!
Mr. Carlson, your videos are quite literally the best of the entire subject of electronics on RUclips.
Thanks for your kind comment Andiar!
People like you are the reason I love RUclips.
REALLY cool video. Not too geeky, not too basic...just right. Thank you and please do more. BTW: reminds me of 500W AM daytimer I worked for in Midland Texas in late 60s KNAM. When it got really cold, I would have to go to work an hour early and turn on the electric space heater in the transmitter room to heat up the transmitter enough for it to function. Other DJs would light the teletype copy on fire with a cigarette lighter when I was trying to read the news literally straight off the wire....a broadcaster's practical joke. Great fun for a teenage kid. I really enjoyed the video, please keep them coming.
Dude... you've impressed me beyond comprehension! Total y awesome and looking to watch more of your video's!
An outstanding video Paul, I enjoyed it very much. I worked as a student broadcast engineer at WOSU while attending Ohio State university in the late 1060's. Their old AM broadcast transmitter was literally a large room you walked into full of large transformers, inductors, and tubes (circa the mid-1920's). Their transformers made yours look little in comparison, maybe the size of a small mini refrigerator. You video brought back memories of walking into that room and being amazed. The old transmitter was replaced with a new one about the size of a standard refrigerator and was mostly solid state except for the final.
And us, I would enjoy learning more about your transmitters and the tuning of these old monsters. Thanks again.
Thanks for the story Chuck, and taking the time to write.
Sorry about the spelling, should not write replies on my phone. LOL
Hey Paul, The local radio station here has it's tower just behind the station. I've been in the building once or twice and seen lots of tall gray boxes in the back of the station that I now wonder but what this is what they were. The station is WSLM in Salem, Indiana and has been around since 2-14-51. I always thought the place was kinda neat. A good friend's father used to work there and he'd let us look around and hang out with him in the deejay booth. That booth had two turntables, low voltage incandescent bulbs on the phone lines coming into the station in place of the bells n the phones that the phone company was less than thrilled about. All four walls were loaded with shelves from floor to ceiling of 78 rpm records that they play on the stations anniversary (Valentine's day) every year. Their jingles and identification jingles are all vintage from back in the 50's and they still use them, lol. Stuff like "Little weather bird look in your crystal ball, is the sun gonna shine or the rain gonna fall? Bwackkk, cloudy and coolerrrrrrr" or a quartet singing "In the heart of the hoosier hills, wslm salemmmmm". I imagine if you ever went to this station you'd either get a kick out of it or shake your head at how antiquated everything is in it. They even have an old flatbed truck parked in back with a vintage World War II anti-aircraft million candlepower G.E. spotlight on the bed they use at special events and stuff. Take care, Gary
Thanks for taking the time to write Gary, great story!
Holy Cow! I have not seen a beauty like that in a very long time. I operated a Gates BC-1G back in the mid-90s. I loved the way the old RCA, Collins and Gates transmitters looked. Very Art Deco.
Thanks for the playlist link to my WLW video. The views peaked!
Looking forward to seeing your other heavy iron!
Gear like this transmitter must be the type of template from which game designers built the props in games like Portal 2. I could swear I regularly tried to flip all the switches, twiddle all the knobs and press all the buttons; alas, no reaction, not in the game, that is. Nice to see a real one! Cheers!
How could one not appreciate the craftsmanship involved - no wonder these beauties were so dependable. I enjoy your knack for introducing complex things clearly with just enough info to whet ones appetite to learn more. I've just discovered your site and became your latest subscriber. Thanks for sharing your gear and knowledge.
Welcome Mark! Glad you're enjoying!
Yessss!so very interested in old timey technology and vacuum tube equipment!pls do more!
Hey, great video Paul. Thank you. I was amazed to see the big components, especially the vacuum tubes. Then I watched a video about a local station, WLW 700am, a 500 KW station. Very interesting.
Mr. Carlson,
I have been following your channel for quite some time, and I have been overtly enthused by your deep knowledge of electronics. I own a small, vintage Hi Fi repair shop here in Austin, TX in the US. I must know, did you go to school for this or did you accumulate all of this knowledge on your own (apologies if this has been covered before)? Keep up the excellent work! I learn something every time I watch, and it's crucial to keep this kind of information freely flowing.
Thanks Drew, I have lots more to share, it's all about finding that time. I may do a "Bio" one day, I don't like to talk about myself (that's no fun) I like to talk electronics :^)
Used to work in radio. We had a beautiful 250w Raytheon backup for the 1kw Gates of 1960's vintage which was used about 13 hours per day. The engineer allowed me to work on these under his supervision since I was a night DJ with a strong electronics background. These are all beautiful works of technical art. Really enjoyed your presentation. 73's de KB4MC /DSTAR via K4CPO Nashville.
Thanks Warren!
"Welcome to another episode of Mr. Carlson glows"...
Valves...Ahhh. My era. Great video around some vintage gear. Oh the memories :-)
Dig it man. I'd like to see you detune the amp and walk me through the setup. Always been fascinated with AM and vacuum tube amplifiers. Even tried reading ham books from the fifties, but never got the hang of it. Love the walk through though.
Wonderful vid! I always love to learn how to use outdated equipment no longer in use!
Wow. Can't believe I've not found you before this. All the stuff I love in one channel. De KE9PW. Subscribed! Thank you.
Wow, that's an impressive instrument! Thanks for sharing!
You're Welcome!
I would love to see how you tune one of these from the very start. Also, could you maybe show a basic bloke diagram of the stages how these AM transmitters work? Thank You!!!
paulscats17 you make a screwdriver from a broom handle,and use it to turn the ferrite slugs 😂
love the tour through the transmitter. I am a ham and not on am so don't have this type of equipment. nice to see its still in use.
This reminds me of the Interocitor from "This Island Earth". As a matter of fact, Mister Carlson looks a little like a younger Exeter himself. Hmmmm........
I really enjoyed your video as it brings back memories of my days working as a Tec'n for an AM station in Ontario from 1974 to 1986. We operated at 630khz 10kw/1kw and had Continental Transmitters and a tower array we switched between day and night. We had a 416C for the 10kw and a smaller 1kw which I have forgotten the model #. I remember when lightning took out the 416C with a big bang. It blew out some of the paper caps and made a mess inside the transmitter. We later upgraded to two 316F Transmitters. Each was setup for 10/1kw so we had one always as backup. The 316F was equipped with a magniphase which would shut down the output in the event of lightning strikes. That was a big improvement at the time over the old ones. I left the broadcast business in 86 for a career in Transformer manufacturing.
Great story Roy, Thanks for sharing it with us!
the station i work for broadcasts at 50,000 watts during the day and 30,000 at night, we recently went to the AM site last week and it was my first time so its fitting to find your video now, we still have the beast from the 60s in the shack, its a continental electronics, its absolutely beautiful not like the new one, its very utilitarian with a touch screen.
That is bonkers.
It's very pleasing to see someone so young restoring vintage electronics, well done that man.
Beautiful rig. Would be interested in hearing more about your VFO design. Have come close to buying a broadcast rig on a couple of occasions, and wondered how I'd manuever it into the ham band.
What's the efficiency of that rig? I'm betting it uses 4 to 6 kW to generate .25 kW of AM. Am I close?
Jason: Great question. There are actually two "efficiencies" in transmitters. The first is the overall number given to apparent and true power consumed from the power mains. This number is generally given as 0.98 or 98%. The power company uses this number. The other efficiency is power output from the tube or final stage. This number can run between 65% to 78%. This number comes from dividing the measured RF output by the DC plate power. AM radio is different from FM because of the class amplification used for modulation.
Your first number is power factor. Your second is plate efficiency. However, between the two is a lot of losses. there's all the drivers and filaments, fans, etc. All the drive power doesn't end up out the antenna, either. Ancient Modulation (AM)* is pretty inefficient because half the power is just carrier when it's fully modulated, and at zero modulation you're still using those kilowatts to put out zero information. So DSB is much better efficiency wise, and SSB is twice as good as DSB in using bandwidth. *Just kidding, of course
James: Yes, indeed, there are a lot of losses in a transmitter. Engineers realize that a reasonable comparison between what it takes to power a transmitter and what it finally puts out is not equal. The power supplies for most, if not all, vacuum tube transmitters are linear. Therefore, not all that efficient. A switching power supply rated for 10,000 volts at 3.1 amps would be a very complicated affair. However, in a linear power supply, the HV transformer weighs 485 lbs, the filament transformer is rated at 10 volts, 165 amps. The filter capacitor(s) are 8 mF 13 Kv. A choke is rated at 15Kv. The rectifier stack has diodes that are really huge. What I am saying is the power supply is relatively simple; it's just big and heavy. The only efficiency factor the FCC requires is either stated by the manufacturer or computed by the ratio of plate DC to final output the the antenna or phaser/matching circuits. You are correct about SSB and DSB, but it's lousy for music.
What I'd like to know, if you'll forgive my silly question, is: When transmitting at 250W, how much power is the rig consuming? Very much enjoyed your video and subscribed.
I really appreciate the effort you put into these video. Things like using a good mic. Getting close-ups. Switching to a wide angle lens to go inside. And taking the time to show what each thing item does. Thanks for making these so professionally. It's really great!
Thanks James!
Absolutely Fascinating!! Thank You, Paul.
Insane to see this again. I worked as an electrical engineer co-op for a navy lab. One of my jobs was to work on this amplifier. We retrofitted it to drive a shaker table in the vibration lab. Amazing that I actually got it working - had to add some reactance in the feedback loop used in the vibration application.
No RF burns? :-)
Not at 250 watts at AM broadcast freqs.
I got an RF burn from a 50 watt rig. Started smelling burning hide, but didn't feel a thing. The rig was on 1180 kilocycles, middle of the BC band. Yes it was a bootleg station. Year was 1959. Reakon the Statute of Limitations has run out by now.
As I remember it, transmitters had interlocks (1975 era) that would sound alarms and shut down.
Loved your vid! Brings back fond memories. As a teenager in the '50s I scratchbuilt a rig using paralleled 6DQ6 finals, plate-modulated. Mod. transformer consisted of TWO 25-cycle power xfmrs connected back-to-back (primary to primary). Two 6L6s in p-p drove the center-tapped HV winding of the first xfmr; the center-tapped winding of the second xfmr carried plate current of the RF final. Audio had a sharp roll-off above 5000 cycles, perfect for voice.
Dumb kid shouldn't think power transformers aren't good for audio, but they worked great.
Idk i remember growing up late a night I could pick channels I usually couldn’t during the day.. some would be from far away an have some static
Awesome job as always!
Thank you!
This is fascinating! Love your work Paul.
Thanks Colin!
How the hell did you get this monster into your house?
Tony through a big door
And the even bigger ones he's got somewhere else!
In pieces....I would guess...as they always tell you ....some assembly required...lol
Step 1: chloroform the wife.
Step 2: Have a beer
Excellent discussion on old technology. I'm always amazed how science and electronics were developed in my time. Your repair Technics on later transistor equipment is fascinating as well as informative. As a Mechanical Engineer I have always been involved and associated in the field but not to the depth of details you explain. Good work and thanks.
Hi, in 1954/1955 I worked at an AM broadcast station transmitter after school and on weekends with several other guys from school. It was a 250 Watt AM station in Upper Michigan and one of the Engineers got several of us involved and mentored us to becoming Hams. I believe our Gates was a 250 C. All of us went on to become Extra Class Hams and to work in various Radio and Communications fields. I was 14 when I worked there, got my Novice ticket in October of 1954.
Lots of good memories of those days. Even got to listen to Detroit Tiger Baseball and Toronto Maple Leaf Hockey as part of Network feed. Nite time down at the Studio, we listened to Elvis's first recordings after hours.
Thanks for all the memories. Best 73's
Bill W6SDI
Thanks for sharing your story Bill!
thankyou for showing us some more of your equipment. your videos always inspire and i enjoy learning from you verry much
That was probably one of the best videos I had ever watched on youtube, thanks for sharing...
Smiling!
Good video sir!
We always called them bread slicers.
I sold lamps to the studio business in So. Calif and was able to see the DC power building at Paramount. Studio cameras did not match up to the alternating power so they converted it to DC. Built in early 1900s. It is beautiful to see. All constantly polished brass and copper wiring with huge transformers. Your analysis of the broadcast transmitter recalled it to mind. Also see huge steam engine at Buffalo Water Works. Same craftsman work.
Really cool video love seeing all the big iron ,and well Big everything inside that transmitter makes working on old tube amps feel like building models on a 1/32 scale. You have a diverse and very interesting channel im very thankful that you share your knowledge.
Would love to see more setup and configuration of the Broadcast Transmitter. Very interesting. Thanks for all your insight and hard work!
Thank you so very much for this tour of your transmitter. I most certainly would like to see further presentations of all that you
mentioned especially tuning the transmitter output.
Those tubes are nuts! Ive never seen anything like that before
I've been waiting for you to demo some of your AM gear for a long time. Please keep it coming!!