[Boatanchors] Comet Pro Help Needed

[Joe Connor]

>I need some troubleshooting help on a basket-case Hammarlund Comet Pro that I'm trying to restore. Here's the schematic: 
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>http://www.nostalgiaair.org/PagesByModel/994/M0008994.pdf
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>Mine is the early model with the only gain control a pot that varies the voltage on the cathodes of the two 58 IF tubes. This one was a real mess when I got it but I love these old Comet Pros so I want to get it performing well. 
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>Here are my symptoms: There is low distorted audio when the gain control is turned fully counter-clockwise. As I turn the control clockwise, the audio gets louder but gets very distorted. Right as it gets to full volume, the audio gets clear but is very, very loud. I can't get clear audio at a lower volume. 
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>I have recapped the set (except for the 1 mfd cap right after the second detector). I disconnected the gain pot and it turns from 0 ohms to the full 12K ohms. (I used a DMM so I'm not sure just how smooth the change in resistance is). The gain pot causes the cathode voltage on the IF tubes to vary between 0 and 13 V. All voltages in the set are in the ballpark. The resistors all test within 20% or so of spec. 
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>Does anyone have any ideas?
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>As always, thanks for your help.
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>                                      Joe Connor
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