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G3SEK Tetrode Boards documentation
Mike, Try this: https://web.archive.org/web/20180408212726/http://www.ifwtech.co.uk/g3sek/boards/tetrode/tetrode-1.htm 73 Bill N4LG
By Bill Cotter, N4LG · #40854 ·
Re: Amp modification
Hi, Would anyone have the G3SEK schematic and PCB drawings for download? The link seems to be broken for me: http://www.ifwtech.co.uk/g3sek/boards/tetrode/tetrode-1.htm Cheers, Mike Peace VK6ADA
By Mike Peace · #40853 ·
Re: Amp modification
I have ran into a couple of those online. Wanted to put one in my Thunderbolt, as it uses the gas filled tubes to regulate the screen, but I was gonna try a string of Zeners soldered into an old tube
By Technotronic Dimensions · #40852 ·
Re: Amp modification
The tetrode boards aren¡¯t particularly complicated if you only implement the screen current trip. On my tetrode amplifier, I eliminated the control grid current trip and ALC circuitry. Their primary
By Mike WB2FKO · #40851 ·
Re: Amp modification
Can't beat the simplicity of a triode amplifier.
By mike repinski · #40850 ·
Re: Amp modification
By Billy Pickering · #40849 ·
Re: Amp modification
Sell your 4CX250's and purchase the 3CX400's ?
By mike repinski · #40848 ·
Re: Amp modification
Main reason for looking into the 4CX250 is I have a ton of them, like 10-12 of them, sockets and chimneys as well. My father-in-law who is also my elmer built an amp around the RF deck of a KWS-1 that
By Billy Pickering · #40847 ·
Re: Amp modification
I cut my teeth bringing an old Johnson Thunderbolt back from the grave. (2) 4-400A tetrodes in parallel....learned a lot. Key to that whole applicaiton is the neutralization....and the fact if the
By Technotronic Dimensions · #40846 ·
Re: Amp modification
I would get the 3CX800 checked out and if good go with that. Socket is the same, filament voltage would need changed and maybe the bias. That should be it. Look at all the Alpha amps that have been
By mike repinski · #40845 ·
Re: Amp modification
Hi Billy, I'm not an amplifier guru. I've studied & repaired a few. There's a notion in the RF amplifier camp that says "if your amplifier needs more than one tube, you need a different design." I
By Robin Midgett · #40844 ·
Re: TL-922 tube filament voltage.
You can buy many decent RMS multimeters like the Brymen BM857 that is a fully safety rated and protected meter that is much cheaper than the Fluke. There are others.? There is a Multimeter comparison
By tardivat@... · #40843 ·
Amp modification
Well, I was lucky enough to pick up a Henry Tempo 2006 that did not have any tubes. Yes, 3CX400A7 tubes are expensive so we were looking into modifying it to run 2 or 3 4CX250B tubes instead. I know
By Billy Pickering · #40842 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
I located a spare Johnson #247 socket (8877). Never been soldered on. Make offer.. Dennis, w8nw [email protected]> wrote:
By Dennis Homerick · #40841 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
###? ?If I remember correctly, the 1st DTR-2000L's had this mickey mouse fan in there for cooling.? Local dealer had the 1st one in stock.? ? We all laughed when we saw the small fan...that
By Jim VE7RF · #40840 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
Ah. OK. I have gold plated ones here that I got from Mableaudio many years ago. I know that they do silver as well. I can add that the sockets have nice spring tension on the pins. That goes for the
By Alek Petkovic · #40839 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
Add says silver plated but yes very nice looking product.
By mike repinski · #40838 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
Yep. Sure is. Superb quality. Gold plated contacts and all. Alek
By Alek Petkovic · #40837 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
The porcelain part of the socket are cheap at hamfest, Johnson 273 I believe. ?It gets expensive with the copper grid tabs. Sent from the all new AOL app for iOS
By Louis Parascondola · #40836 ·
Re: Tube socket for 3CX1500A7 tube-socket broken
Is this socket a copy of the Johnson socket with the same mounting hole locations? Mike
By mike repinski · #40835 ·