Im confused. You said AM aligned fine, but then you said that you got nothing on TP5 or TP6. Didn't you use TP5 when aligning AM?
I wouldn't expect to see anything at TP6. That test point is fed via a 5pF cap. Whatever probe you have likely has way more capacitance, plus the counter input of 15-20pF. You should be able to see the signal at the emitter of the oscillator with a 10x probe, but the probe will certainly load the oscillator and shift its frequency some. Can't do alignments that way without an active probe, and even then, it will still shift it by 5-10Hz.
You said AM aligns fine, but neither sideband will go lower than 10.71MHz. That makes me think the band switch isn't sending power.
The first step in troubleshooting frequency problems in a crystal oscillator is to have an understanding of what direction added reactance will pull a crystal.
Relative to a crystal connected to ground with no pulling, adding inductive reactance lowers the frequency and added capacitive reactance raises it. The two extremes to that are when there is so much inductive reactance that it behaves more like a LC oscillator (loses benefit of having a crystal) or so much capacitive reactance that the oscillator fails to operate or becomes so sensitive to its surroundings that it becomes a useless theremin.
With the frequency being way too high, I am led to believe that the tuning inductors are not in circuit in sideband. When I was playing with high-Z jfet oscillators, they would still oscillate even if the lower crystal leg was lifted and not touching anything (just at a higher unstable frequency). Your situation is similar where the inductive portions don't seem to be in the circuit.
Since probe loading adds capacitance (and therefore lowers the overall capacitive reactance), I would expect a decrease in frequency in response to the oscillator being probed, so I don't think this 10.71 is due to probe loading. Also, with two paths sharing the same problem, that makes me think a lack of voltage, not a bad diode or lost coil continuity.
I would check for voltage at R162 in each mode to ensure the band switch is sending sufficient voltage to each leg of the oscillator. If voltage is not present in sidebands, trace it back to the switch verifying diode health and coil continuity etc until you find it.
I wouldn't expect to see anything at TP6. That test point is fed via a 5pF cap. Whatever probe you have likely has way more capacitance, plus the counter input of 15-20pF. You should be able to see the signal at the emitter of the oscillator with a 10x probe, but the probe will certainly load the oscillator and shift its frequency some. Can't do alignments that way without an active probe, and even then, it will still shift it by 5-10Hz.
You said AM aligns fine, but neither sideband will go lower than 10.71MHz. That makes me think the band switch isn't sending power.
The first step in troubleshooting frequency problems in a crystal oscillator is to have an understanding of what direction added reactance will pull a crystal.
Relative to a crystal connected to ground with no pulling, adding inductive reactance lowers the frequency and added capacitive reactance raises it. The two extremes to that are when there is so much inductive reactance that it behaves more like a LC oscillator (loses benefit of having a crystal) or so much capacitive reactance that the oscillator fails to operate or becomes so sensitive to its surroundings that it becomes a useless theremin.
With the frequency being way too high, I am led to believe that the tuning inductors are not in circuit in sideband. When I was playing with high-Z jfet oscillators, they would still oscillate even if the lower crystal leg was lifted and not touching anything (just at a higher unstable frequency). Your situation is similar where the inductive portions don't seem to be in the circuit.
Since probe loading adds capacitance (and therefore lowers the overall capacitive reactance), I would expect a decrease in frequency in response to the oscillator being probed, so I don't think this 10.71 is due to probe loading. Also, with two paths sharing the same problem, that makes me think a lack of voltage, not a bad diode or lost coil continuity.
I would check for voltage at R162 in each mode to ensure the band switch is sending sufficient voltage to each leg of the oscillator. If voltage is not present in sidebands, trace it back to the switch verifying diode health and coil continuity etc until you find it.
