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Another aspect, is to know if the TX crystal is the one HIGHER than the expected RX frequency?

Because to the system, the TX side uses that offset - but the High/Low switch that gives the radio all it's bands - can throw you for a loop - so the D33 and D123 have to be verified that they are working.

The other offset? Deals with TR30 - the TX 10.697 X4 - see if that frequency is supposed to be what it is. It is not used in the PLL side - but the RX does have a deviation pot VR5 - now it affects the Varactor, for the PLL.

So if FM-2- AM issues show up - it may be in this area - VR5 and the two Diode splitter D31 and D32. It may not affect the frequency directly - but if the cap used to "vibrate" the Varactor with audio - can fail - and load down the line that the Varactor tunes with. That fluctuation as a frequency shift, can show up on TP2.

<blockquote data-quote="Handy Andy" data-source="post: 785669" data-attributes="member: 52309">Another aspect, is to know if the TX crystal is the one HIGHER than the expected RX frequency?Because to the system, the TX side uses that offset - but the High/Low switch that gives the radio all it&#039;s bands - can throw you for a loop - so the D33 and D123 have to be verified that they are working.The other offset? Deals with TR30 - the TX 10.697 X4 - see if that frequency is supposed to be what it is. It is not used in the PLL side - but the RX does have a deviation pot VR5 - now it affects the Varactor, for the PLL.So if FM-2- AM issues show up - it may be in this area - VR5 and the two Diode splitter D31 and D32. It may not affect the frequency directly - but if the cap used to &quot;vibrate&quot; the Varactor with audio - can fail - and load down the line that the Varactor tunes with. That fluctuation as a frequency shift, can show up on TP2.</blockquote>

[QUOTE="Handy Andy, post: 785669, member: 52309"] Another aspect, is to know if the TX crystal is the one HIGHER than the expected RX frequency? Because to the system, the TX side uses that offset - but the High/Low switch that gives the radio all it's bands - can throw you for a loop - so the D33 and D123 have to be verified that they are working. The other offset? Deals with TR30 - the TX 10.697 X4 - see if that frequency is supposed to be what it is. It is not used in the PLL side - but the RX does have a deviation pot VR5 - now it affects the Varactor, for the PLL. So if FM-2- AM issues show up - it may be in this area - VR5 and the two Diode splitter D31 and D32. It may not affect the frequency directly - but if the cap used to "vibrate" the Varactor with audio - can fail - and load down the line that the Varactor tunes with. That fluctuation as a frequency shift, can show up on TP2. [/QUOTE]

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