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Old October 5th 03, 03:50 PM
W3JDR
 
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It really doesn't matter what frequency the application is, modern
transistors have good gain well into the UHF range and VHF parasitic
oscillations can occur even in an audio application

Joe
W3JDR


"Paul Burridge" wrote in message
...
On Sun, 05 Oct 2003 13:27:59 GMT, "W3JDR" wrote:

John,
Can you post a picture of your unit somewhere(top and bottom views) so we
can see what the PCB & wiring layout looks like? Many times an improper
layout can lead to parasitic oscillations that will raise DC power
consumption without delivering RF on the proper frequency.


It's worth a try, John. But 7Mhz is practically DC these days so
strays and paracitics shouldn't be too much of a problem. One thing I
meant to suggest in my earlier post was that the OP should try
transmitting into a known good 50 ohm dummy load and seeing if his
final tranny still gets as hot. That ought to be a real good clue as
to whether he does have some probem with his matching/antenna/feedline
etc..
--

"Windows [n.], A thirty-two bit extension and GUI shell to a sixteen bit

patch
to an eight bit operating system originally coded for a

four bit
microprocessor and produced by a two bit company."