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previous: andyfuchs I agree with Gil, coax on low level... -- 5/20/2000 8:39 PM

Re: Shielded input cable question

5/20/2000 9:56 PM
Lee M.	Re: Shielded input cable question Re: my AX84 November oscillation problem: Today I rewired the channel 1 jacks. I found one mistake, I had the shield of jack #2 grounded to the shorting lug instead of the ground lug. I replaced the RG174 shielded cable on jack #1 (which was about as short as it could be) with a longer length of plain wire which I routed along the end of the chassis and then (making a 90 deg) turn, over to the terminal strip (to which the grid stopper resistor is attached.) This reduced the oscillation dramatically (although I still get it on certain notes) but I may be getting more hum, especially with the gain up high and the (single coil) guitar close to the amp. Question: should I go back to shielded cable now but use a longer length to keep the new routing or should I play with more lead dress changes until the oscillation is completely eliminated? Thanks. Lee

5/20/2000 9:56 PM

Lee M.

Re: Shielded input cable question

Re: my AX84 November oscillation problem:

Today I rewired the channel 1 jacks. I found one mistake, I had the shield of jack #2 grounded to the shorting lug instead of the ground lug. I replaced the RG174 shielded cable on jack #1 (which was about as short as it could be) with a longer length of plain wire which I routed along the end of the chassis and then (making a 90 deg) turn, over to the terminal strip (to which the grid stopper resistor is attached.) This reduced the oscillation dramatically (although I still get it on certain notes) but I may be getting more hum, especially with the gain up high and the (single coil) guitar close to the amp.

Question: should I go back to shielded cable now but use a longer length to keep the new routing or should I play with more lead dress changes until the oscillation is completely eliminated?

Thanks.

Lee