Those tubes will be rather used in class B. Without grid-current they put out 1200W at 3,5KV anode voltage, with a total of 13mA grid current it will be about 1600W. On using the formula Ep/x*Ip one
Hi Peter, Is it also the same weight? There are also pretty small vacuum variables around, much smaller then any breadslicer 73 Peter There's an interesting article on a 1500 watt Class E amp in the
Hi Frank, What did you wrong with your 4CX3000A amplifier? 73 Peter The class e Amplifier project can be down loaded for free by going to the ARRL QEX site. Then down load the sample article for Nov/
Hi Patrick, I built one in push-pull about 20 years ago, worked fine and is still in use at a friend shack. Nowadays I would use the GS-35B in PP, much easier 73 Peter Hi all, Almost everything is in
Hi Tom, The wideband RF-preamplifier in the TA1800 by Racal uses 4 parallel 2N3553 in common base, transformer coupled in and out, it does 10db, but standard level of that stage is 50mW in 250mW out.
Hi Tom, I put diagrams of the Harris linear and the Racal widebanddriver on the following website: http://www.pbase.com/df3kv/gallery/linear By the way, the TA1800 also uses 10db of negative feedback
Marv, You are a lucky man with only such few parts missing. I am also busy with 5 or 6 amp projects and a lot more is missing, by the way also the Comet CV03C-1000 and the small fixed version around
All the tubes of the 4/400 family (tetrodes) manufactured by Valvo, Siemens, Telefunken etc. have graphite anodes. Those anodes are already dark red at idle current and become dull red or orange at t
There is another tapped coil made of tube visible. One complete winding to move from 10 to 11m is too large with that tube and its high output capacity. The taps on the coil above the tube are for 10
In a 3-phase environment which is standard nowadays in central Europe that is no problem at all, at 20KW input you need 28A per phase. It is very unlikely that you get corona on the antennas with jus
The difference in gain of a 1/4 wave vertical with 16 1/4 wave radials over good ground and a dipol at 1/2 wave height is also 8db... Stations with beams should never compete with owners of simple an
I would not pay 1$/Euro a watt. It looks as old amps like TL922, L4B,SB-220 etc. cost more used then new. I would not consider an amp kit selling like mad, who is able to properly solder a PL259 plug
you are right nobody should believe what is told on the reflector ;-)) The name of Huber and Shuner could not change as the company is and was not existing. You mean Huber+Suhner in Switzerland (HUBN
Geert, what capacitance did you take into your calculations for C-tube-input, choke and strays? 73 Peter Von: "Geert Hofman" <Geert_Hofman@Jabil.com> An: <amps@contesting.com> Gesendet: Dienstag, 3.
I guess the GS31 is pretty similar to a GS35b, from the data sheet the input impedance of those are 25-40 ohm per tube 73 Peter Von: "Phil Clements" <philc@texascellnet.com> An: "'Geert Hofman'" <Gee
Hi Chuck, I think your anode voltage will be a bit high. The GU84B is a medium voltage, high current tube and normally sees 2,2KV. With the high impedance at 4KV you will run into trouble on 10m as t
yes, with yours there will be no problem on 10m, the output Ra is pretty low with 500 ohms and 130pf minimum c-tune are fine on 10m for a Q of 12. Chuck with one tube, the higher voltage and lower ou
I don´t think so, as a 8171 is much cheaper to obtain and it is well known for its reliability 73 Peter --Ursprüngliche Nachricht-- Von: "PA3DUV" <pa3duv@planet.nl> An: <amps@contesting.co
Hi Tom, those two were 1000MP Mark V used on different locations. It happened almost incidently to both rigs during a hot summer period. Both rigs were installed in a typical shelf put on a desk with
I have the impression that will be used for a ht-meter circuit, that can´t be done with a normal resistor, a 5kv type will be required, the 5x1M Ohm might do it if they are spezified to handle