Check for intermittent preset pots on the 2nd IF board. They're all shot on
mine.
If you replace them, fit multi-turn pots.
On 20-Feb-10 20:25, Jim Shorney wrote:
On Sat, 20 Feb 2010 11:13:53 -0500, Craig Roberts wrote:
HOWEVER, the power meter is now acting up and no amount of
re-calibration will help. Forward power readings are fine -- but keying
the transmitter in the reflected power postion causes the meter needle
to drop below zero. This also happens in the forward power position when
the rig's keyed with carrier or mic gain control at minimum.
Craig,
The zero reference voltage for the meter comes from the 2nd IF/Audio board.
This should not change between RX and TX, so you may need to check the zero
adjust (R1128) as described in section 3-2 (S-Meter adjustment) of the service
manual. This adjustment, as well as several others in the radio, rely on proper
setting of the +10V. If the +10V has changed or been adjusted, you will need to
re-align the S-Meter/ACG adjustments, and probably the fixed passband
adjustments as well. The +10V adjustment is the first adjustment in the service
manual, and must be accurately set before any further alignment is preformed.
Hope this helps.
73
-Jim
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