• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

K-502 Left Channel is out

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I just assembled the kit. First run it worked great. :) I was excited... its my first DIY. I had trouble with the pot on second run and decided to replace it since all solder joints were good. I replaced the pot with a radio shack A100KX2. Its a 100kOhm .5W Dual pot. I grounded it with the lug. I turned on the amp and had lost the left channel totally, except that it still pops when powered up. All tubes glow. I replaced the pot with an exact match to the B100K that it came with. Still the left channel is missing.
I got out the multimeter and tested every resistor and cap. I think the multimeter is bad (its a chinese cheapy from ebay). Maybe I need to get another, but multi's that read caps up to 2ooouF are expensive. It read many caps and resistors but some of them it would not read AT ALL. I figure a bad cap will still give some reading and a bad resistor should still have some resistance.
I have yet to hook it up to the transformers.
So far, any suggestions? Has anyone dealt with this before?
 
Well, I had removed the first pot and used a copper braid solder wick to remove the solder. I was again using the multimeter and working through all caps and resistors when I noticed that there was a tiny piece of that copper braid shorting two legs of the pot on the left side. I removed it and still no music out of the left channel. So while the amp was on I wiggled each wire (I soldered 6" 24gage copper wire legs from the board to the pot). When I wiggled the wires the RIGHT channel went out and I could hear a faint bit of music coming from the left. Dear lord give me patience :) and a better soldering hand.
So I will resolder all those joints and see what happens. Probably should use a another new pot just for good measure.
I will post results within the hour if my parents dont show. They will be here soon for Easter Weekend. I hope you all have a fun and happy Easter :)
 
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