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Let me describe what's going on with the very first "null" of the top slug of T-103. I have the HP 8601A set as follows. Frequency is 21.25 MHz continuous. The output is 1KHz AM modulated at 10mV. It is being fed through a 1500pf cap into pin 1 of V2. The coaxial ground lead is clamped to the chassis. The VTVM is set to AC 5V range and was zeroed prior to connection. Probe is connected to pin 1 of V106 and grounded to the chassis. The 10mV RF output is the minimum output strength that can be adjusted to 3V AC but strong enough that interference, like touching the coaxial lead, doesn't cause deflection of the VTVM needle. Tuner is between channels 2 and 13.
I've turned the upper slug in T-103 a couple of turns clockwise and counter-clockwise from the initial position is resulting in no change on the VTVM.
I've checked and rechecked the connections and they are all correct. Is the RF output voltage too low? Shouldn't I get some VTVM deflection with those slug adjustments I made?
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