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BYPASSING A GAIN STAGE - QUERY
#11
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Thanks for the info and advice, Kevin.

After thinking about the options and inspecting the PCB again; I decided to cut some traces and make the existing relays do the job.
A bit time consuming, but less work than adding a relay and having to worry about loading the switching supply.
It has worked out fine, after some strategic wiring.

I wired the Clean Volume in normal mode, between ground and R6 and wired the wiper to Pin 9 of Relay 1B, Pin 11 to RA5/RA6.
I connected Pin 4 of Relay 1A to the wiper of the Drive pot, grounding it in Clean mode.
I swapped connections on Pins 9 & 13 of Relay 2B and connected Pin 11 to Pin 11 of Relay 1B, which grounds the junction of the Stage 2 output voltage divider, when in Clean mode.
So I now have Stage 3 selecting Stage 1 or Stage 2 output and mutes on the Input and Output of Drive Stage 2 when in Clean mode.

This should now take care of the switching and eliminate any Drive bleed-through. 
I can reassemble tomorrow and see how it sounds.

Thanks for your patience and help.

Noel
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Messages In This Thread
BYPASSING A GAIN STAGE - QUERY - by NGW - 09-11-2019, 12:45 AM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-11-2019, 02:57 AM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-11-2019, 04:40 AM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-11-2019, 11:47 PM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-12-2019, 01:22 AM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-13-2019, 10:23 PM
RE: BYPASSING A GAIN STAGE - QUERY - by NGW - 09-17-2019, 10:44 AM
BLUES DELUXE MODS-UPDATE - by NGW - 03-09-2020, 06:41 AM
RE: BYPASSING A GAIN STAGE - QUERY - by nauta - 03-09-2020, 10:05 AM

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