Re: UHF FM Transmit Power


Helmut Wabnig
 

On Sat, 24 Mar 2018 08:05:37 -0700, you wrote:


Replacing the UHF PA is relatively simple.  But getting to it takes a little work.  The driver board is soldered to the PA board, so it has to be unsoldered. 

No, you do NOT remove the PA board to replace the UHF transistor.
You have to remove the PA only for the driver.

Just remove two screws, unsolder the cover which is over the UHF
transistor, plug in the new one, screw&resolder the cover shield
and that's it. Takes 30 minutes.
No adjustments necessary, although it is ok to do with older IC7000
units because electrical parameters shift over time.
The adjustments are tricky and complicated,
better leave as is.
The main difficulty is to get exactly 3, 20 and 30 mVolt 1500 Hz
at the microphone input. Everything else is straightforward.
And you must provide exactly 13,8 Volt at the transceiver DC input
during transmit!

OE8UWW

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