Please Help with two problems...

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I have installed a new volume pot in my Jolida 302b integrated tube amp. I also replaced the stock signal wire from the RCA's into the main PCB throught the pot.
TWO PROBLEMS: Sensitive pot - very high gain and a LOT of RFI noise through the speakers.
First of all, I used shielded coax cable for the signal wire, one for left channel and one for right. The cable (cheap cable) consists of a vinyl jacket over braided copper shield over teflon coated 20ga. stranded shield over 20ga. stranded conductor. I have tied the stranded and braided shields together and soldered them to the RCA grounds and the signal wire to the RCA positive terminals. I then terminated the other ends of the wires to the volume pot and soldered the grounds from the two cables together and to the volume pot, so that there is a continuous ground from the RCA ground through the pot to the ground at the main PCB.
The pot is a TKD pot from Michael Percy Audio. It is 50kohm which is what the stock pot was. It measures 47.8kohm at min. volume and .5kohm at max volume. The right and left channels measure close to the same, but not equal.
When the amp is on and volume is at a minimum, I still get sound out of the speakers. When I just start to crack the volume on, I get volume out of the right, but very little from the left channel. Then as I crack it open a little further, I get a LOT of volume out of both channels. It is very sensitive and it appears that I have a LOT more gain than with the stock pot. The stock pot in these amps can be found at Radio Shack for about $1.50 - I am not kidding.
Why is this happening? Is the TKD just a lot more efficient (less losses) than the stock pot? The sound is much clearer BTW and sounds great, except for the RFI.
Do I have the input wire shields connected wrong. I wired them in the same configuration as the stock wires. I am wondering however, if I should just ground the shields at the RCA grounds and leave the other end ungrounded. If so, do I still ground both common legs of the volume pot to the main PCB ground?
Any help here would be appreciated, I am baffled and frustrated.
Thanks in advance,
Dan W.

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Topic - Please Help with two problems... - Dan W 09:18:35 07/19/00 (4)

Re: Please Help with two problems... - Dan W 13:47:24 07/19/00 (1)

Re: Please Help with two problems... - tenor39 17:36:45 07/19/00 (0)

Re: Please Help with two problems... - tenor39 12:41:50 07/19/00 (0)

Re: Please Help with two problems... - Dave I 11:17:42 07/19/00 (0)

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