{Collins} 32S-3 grid meter pins backwards immediately upon turning on the unit



I have a 32S-3 that I recently acquired that has several problems.?? The first of which is that immediately after turning it on (the FREQ. CONTROL is switched to Trans VFO) the meter, if it's in the grid position, pins backwards.?? The MIC GAIN is at minimum and the position of the MODE switch has no affect on the backward pin.?? This happens whether or not the 5R4 and 5U4 rectifiers are in the power supply. ?? In the ALC position the meter reads 0, and in the PLATE position it reads about 40 ma if the rectifiers are in the power supply or 0 if they aren't which seems normal indicating the meter isn't the problem.?? Studying the schematic I can't see where there would be a source that would provide current through the grid meter resistor (R54) opposite of the normal grid current direction thereby causing the meter to pin backwards.?? At first I thought it may be a leaky bypass capacitor, like C84 or C62.?? I temporarily disconnected C84 from ground but the grid meter still pinned backwards, so that isn't the problem.?? From Fig. 6-7 in the manual it looks like C62 is under the aluminum shield covering the rear wafer of the band switch.?? I removed this shield but for the life of me I can't find C62, a 1000 pf ceramic disc capacitor, there or anywhere nearby as far as I can tell. Was C62 not in the circuit for some units and in it for others? Before powering up the 32S-3 I checked all the tubes and found 6 questionable ones that I replaced, and I made the resistance and voltage checks per the instruction manual (Table 4-2) and the readings look to be reasonable for the most part.?? Any thoughts on what to check would be greatly appreciated because I'm stuck! Thanks.?? 73, Gary W8KM




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