Mainline stepped volume issue

Loquah · 1577

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Offline Loquah

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on: August 16, 2022, 11:35:04 PM
My Mainline has been working gloriously for years now and I love it to this day. Just in the last little while, I have begun noticing that a slight pressure on the coarse side stepped volume knob can cause a large jump in volume level and to the right side channel more than the left (perhaps entirely in the right channel - I'm trying not to hurt my ears with extended testing).

Before I reflow the entire attenuator, does the described issue of placing slight pressure on the volume knob off to one side (it doesn't seem to matter which direction I push) lead to any obvious places to focus my attention? To be clear, it takes only as much pressure as you'd use to adjust the volume so it seems like a broken joint or crossed connection that's being altered with minor movement of the attenuator itself or the spline within the attenuator.

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Offline Paul Birkeland

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Reply #1 on: August 17, 2022, 04:32:38 AM
I would suggest looking at where the coarse resistors come off the attenuator switch and connect to the black ground wires.  The resistors on the switch themselves aren't really going to know that you're putting pressure on the switch, as they are all mounted to the switch themselves.  If the right channel resistor to ground on the coarse side is just every so slightly loose, this is the exact problem I would suspect.

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Offline Loquah

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Reply #2 on: August 17, 2022, 06:31:19 PM
I would suggest looking at where the coarse resistors come off the attenuator switch and connect to the black ground wires.  The resistors on the switch themselves aren't really going to know that you're putting pressure on the switch, as they are all mounted to the switch themselves.  If the right channel resistor to ground on the coarse side is just every so slightly loose, this is the exact problem I would suspect.

Perfect! I'll start there and reflow those connectors once I get the C2A up and running

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