Steve, K1SG asked in his original posting experience with 7/16 DIN connectors from China which are coaxial. Quite possible that Ryan mixed that up already. 73 Peter It seems to me we are talking abou
Who manufactures a 4CX800? Is that not a pseudo designation of the GU74b, as they do with the GU43b which the Russian dealers advertise as a 4CX1000? OR the GI23b as a 4CX1600? My calculations for cl
That is the same efficiency as with a 8877 at that voltage. It will be much better at higher anode voltage. 73 Peter Well, I have finally completed this project...All electronic circuits perform faul
What is a 4CX800? Was never made... But it is true, tetrodes can not replace triodes without a major redesign 73 Peter --Original Message-- From: amps-bounces@contesting.com [mailto:amps-bounces@cont
Hi Roger, Eimac 4CX800 never existed. American amps and other were built for some time by using NOS Russian GU74b, probably dropped from a military storage shelf 73 Peter the So the Eimac the America
Hi Arno, I would prefer you send me a photo of a 4CX800A7. Neither Alpha nor Acom amps have 4CX800 tubes built in, all are GU74b. I can design you a datasheet with whatever you like to include within
Hi Arne, The Alpha amps were made in Bulgaria at the place which is today known as ACOM. All ACOM amps are supplied with GU74b. I don´t remember what year (late 90)Mike Matthews from New Sensor (Elec
Hi Kees, Who is the tube seller? Is that this one: http://www.wvs-tech.de/wvs-tech/index.php?site=wvs 73 Peter Hi Carl, In that case I cannot help you I guess. I do not have connections directly to t
Interesting to read that they even made a 4CX800A7, rumours never end. First time I hear about it. What stands the 7 for? Another tube which will be no replace for the tubes of a Titan 425. 73 Peter
Most probably the GU-81, 800W anode dissipation convection cooled. http://www.pbase.com/df3kv/gu81_at_friend 73 Peter A while back I saw a surplus glass Russian tube that resembled an 813 on steroids
The transconductance of that tube is given in the original data sheet at 23mA/V, so the input impedance of a single tube will be 43 ohms. A 2:1 transformer will match to 25 ohms. 73 Peter I have been
That will work pretty well. The loading capacitor in the Tentec Titan 425 is made that way. There is also a relatively small 3nF unit available in The Netherlands which I bought them for amplifier pr
In a right built amplifier one would not use series connected electrolytic caps in the power supply. Individual, adjustable bias for what reason? How do you bias for best IMD with more then one tube?
I tried that choke in one of my amplifiers without testing it first with the GDO and it just turned into smoke on 10m. 73 Peter ORIGINAL MESSAGE: right at the cold end, made several differences in ci
For my other amplifier I wound a similar aperiodic choke in 1975, that never failed. But that is only 110µH and the amp is just 10-80m. http://www.pbase.com/df3kv/image/33238173/original 73 Peter I t
OK, lets talk about a water tight chassis used for a GG amplifier. The grid of the tube is screwed to the top of the chassis. Under the chassis the driving signal is connected via a pi network to the
Where is that padder cap connected to if not through a hole in the chassis to the band switch? 73 Peter ORIGINAL MESSAGE: REPLY: For the third or fourth time, you are talking about RADIATED RF energy
For the YL105x family of tubes the manufacture suggests to heat it permanently at 3.5V. The nominal heater voltage is 3.8V. The heater voltage of the 4CX10000D in the Racal amps in stand by is heated
Peter, you are right 73 Peter Isn't it the anode voltage swing instead of the anode voltage ? Pse discard if I'm wrong. 73, Peter, PE1E snip...(Peter ) In the case of a tube running _________________
Hi Gerald, Sure, it is not critical at all within limits. But the results will be quite different when tubes with high screen voltage are selected for an amplifier. Just to answer the question by Pet