Every video of yours I get into I find myself cursing the RU-vid algo for preventing me from finding this channel years ago. Your stuff is great and I’m learning a ton. Thank you!
I'm unlikely to build something like this but enjoyed the learning curve. Especially the differences in AM and SSB amplification and their requirements. The efficiency characteristics were an eye opener too. Looking forward to part two. Thanks for doing this Mike.
Thank you very much for this video. I've been trying to teach myself about tubes and biasing networks etc. I find there's not enough of these kind of videos on RU-vid for people interested in two amplifiers. I would love to build myself a high-powered all mode tube amplifier someday like possibly an 8:11. But I am going to start small and keep it simple at first until I understand more about the subject. Thanks again and best 73s
That great. I use AL572 amp with 572/B tubes. with amps like mine or 811A type running AM is hard on them. reduce drive to save tubes. MY AL572 has a special bias when running SSB between words the bias cuts down saving heat. for FM and CW you can bias class C . also large AM transmitters are using AMC modulation big saving's on input power. and the station I worked at can go 120% mod. on AMC . Funny I just ordered some 6164B Russian tubes. I have China and GE 6146W tubes now. I made AM transmitters. I used cathode modulation. with 6164B , 73's
For what it's worth, The question brought up by folks as why you didn't use a SS linear because it's simpler, both of the amps look about the same to me with regard to skill. I'm glad you're using a tube. 😉 👍
It is always better (6146 circuit) better to derive the screen supply from the plate supply to avoid losing the plate supply while maintaining screen Voltage. (which would burnout the screen wires) The 807 and 826 tubes (used in class "B push pull) are zero bias minimal plate current and distortion for linear amplification. Ron W4BIN
Some tubes (many peanut tubes) have the suppressor grid brought out separate from the cathode. Super easy to modulate with some negative V and an electret mic into a step up audio transformer. I used a carbon mic just to match the project as it was written in 101 Easy Ham Radio Projects. The vids before go through the little TX.
I suspect there were mobile transceivers that used 12V vacuum tubes with a 12V B+ i.e the tubes that were developed in 1957 when the transistors of the day were not ready for prime time.
Yes all of the two-way radios used tube drivers and finals late in the semiconductor era; development continued well into the 60's. The 12V versions of the 6146 are many.. 6883, 8552, 8032 etc.. The Compactrons and other really high performance tubes like the Motrac Finals were manufactured up until the 70s.
Can't wait for part 2. Don't use up all the 6cl6s and 6146 tubes, I have a couple HW-101s left to rebuild. Where did you get the shirt btw? I just put that sticker on my toolbox. Also I fully support your decision to not build with cold heartless solid state.
Mike, I too had problems getting 'purported' power out of the 5763s. Even in class-C, I've heard stories of north of 10-12 watts! I finally ran across some Tungsol data that showed useful power at class-C to be 6.4 watts; which is more in line with what I've seen Also Mike, did you consider the 2E26, I would think that it would fit perfectly in what you are doing and be loafing at it (?). Finally, I have some (REALLY) bizarre dual VHF/UHF tubes that would probably be cute as CW transmitters! 73...
There's a few folks running 50-100kw AM on 11M so I see what you're saying about 100w is enough -- Average person can't afford to go higher (price and legality).
