Ceramic Mushrooms

(The G0MJW Valve Pages )

There are many valves about suitable for amateur use. What I am trying to get together here is a set of data and possibly a few designs for the VHF/UHF bands. A few recommendations from the experts as well if they will share their knowledge. I have gathered some short form data for some popular devices. I am still putting this information together so please Email me if you have any additions or corrections.

A great supplier is RF Parts. Most of the valves listed are available in the UK, but at greatly inflated prices. The internet helps in this regard. Eastern European valves are available from several sources, e.g. Alex UR4LL.


  1. 2C39A - Only 100W but good to 13cms
  2. 3CX100 - Similar to 2C39A
  3. 3CX400 - 400W. Good to 1GHz but expensive, used in old Henry Tempo amps
  4. 3-500Z - Well used at HF zero bias valve. Full ratings to 110MHz but can be used to 2m.
  5. 3CX800 - 800W. Just manages 70cms, used in the Henry Tempo 2002A,2004A
  6. 3CX1200 - 1.2kW a big 3CX800 or a little 3CX1500. Useable on 2m. Tough 50W grid dissipation.
  7. 3CX1500/8877 -1.5kW on 2m? Expensive but good for the ego. Can work on 70cms at a struggle
  8. GS35B - A Russian coaxial tube, with 1.6kW dissipation and good to 1GHz (Cheap!). Excellent buy.
  9. Miniature Microwave Valve - Not all russian Triodes are huge.


  1. 4CX250B - Surely everyone has one. Usable to 500 MHz Abusable to 400W
  2. 4CX250R - Ruggedised version of the 4CX250B - The one to buy new.
  3. 4CX250K - Coaxial base version of the 4CX250B rated to 1.2GHz.
  4. 4CX350A - An upgraded linear 4CX250 capable of 400W to 144MHz
  5. 8938 - What is this doing here - It is essentially a 4CX250R with a bigger anode rating.
  6. 4CX400A - Svetlana have released this. It is like a 4CX250R but 400W dissipation.
  7. 4CX600J - Some 500 watts on 70cms! Only needs a small mortgage. Delicate, odd base pin out.
  8. 4CX1000 - 1 kW dissipation. Hard to make work at VHF but great if you can.
  9. 4CX1500 - 1.5 kW and much easier to use than the similar 4CX1000.
  10. 7213 - 1.5 kW through 23cms - More common DOD006 is similar and cheap - don't be put off by the ones with welded wire connections as these are easy to remove.
  11. YL1050 - A Siemens valve with 1600W dissipation up to 400 MHz
  12. GS-23B - Russian tetrode. 1600W dissipation to 1 GHz and cheap.
  13. 4CX3000A - 3kW on 2m ? This is getting silly. EME only.
  14. 4CX??? - I wonder what this is ?

Last Modified 26st August 2000