[AMRadio] ceramic tube tester


Peter Markavage manualman at juno.com
Thu Oct 9 20:22:37 EDT 2008


QRZ bio, and on your home page, you indicate your "favorite frequencies" 
are 3870 KHz and 12.263 MHz (Collins Radio Group).

Pete, wa2cwa

On Thu, 9 Oct 2008 16:30:26 -0700 "H.L." <hl at sfsu.edu> writes:
> 
> I finally got my 1966 TMC linear amplifier operating, but with a 
> modulated AM (MCW) input, my Wattmeter indicates an anemic 25 Watts 
> 
> into a dummy load with a total PA plate current of 200mA (nominal 
> current reading according to the manual) for the two parallel 
> 4CX250b's. The manual claims 200 Watts CW! Perhaps one or both tubes 
> 
> are weak. Perhaps a resistor or capacitor has changed value. I just 
> 
> don't know yet and may have to put it on the bench again.
> 
> If anyone knows of specific tube testers that will test ceramic 
> transmitter tubes, such as the 4CX250b or the 4CX350a, please share 
> 
> them with this list.  Many amplifiers and transmitters use these 
> tubes.
> 
> 73 Hal KK6HY
> 
> P.S. I am still interested in TMC transmitter and amplifier original 
> 
> prices to share with the group.  So far, no one has responded.  TMC 
> 
> certainly seems to have kept their prices well hidden.


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