Replacing Turret Board Components

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JMPGuitars
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Re: Replacing Turret Board Components

Post by JMPGuitars »

mkel2010 wrote:
Wed 05/05/21 6:28 pm
OK. I think I see the difference: You're position is that the preamp bus ground is attached at the input jack instead of the chassis ground point shared with the input jack in my layout, correct?

Can you help me understand how the two grounding schemes are different and why one is better than the other (trying to learn is the reason for the question?) I've tried to find explanations that are understandable but haven't had a great deal of success.

If I change the ground bus to the input jack, does it matter to the effectiveness of the ground connection which of the input jack ground lugs is used?
Getting closer. Connect all preamp grounds with as short as possible wires to the bus. Then connect the bus to the input jack, and the input jack to ground. I typically connect all the pot grounds to each other, then run 1 wire to the bus. You want as few antennas as possible.

I just looked at your build thread again. Your heater wiring is also a potential noise problem. Heater wires need to be nice and tight and clean. For example:
heater-wiring.jpg

Lead dress can cause all kinds of issues. Work for a nice clean build, and that's what you'll get. And don't run plate + grid wires parallel or they'll squeal.

Thanks,
Josh
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Re: Replacing Turret Board Components

Post by mkel2010 »

JMPGuitars wrote:
Wed 05/05/21 7:50 pm
mkel2010 wrote:
Wed 05/05/21 6:28 pm

If I change the ground bus to the input jack, does it matter to the effectiveness of the ground connection which of the input jack ground lugs is used?
The way the input jacks are wired, there are 5 potential connection lugs, all connected and then grounded to the chassis. Should I use the same connection point as the ground from the input jack to chassis or can I use one of the other grounded lugs on either of the input jacks?
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Re: Replacing Turret Board Components

Post by JMPGuitars »

mkel2010 wrote:
Wed 05/05/21 8:14 pm
The way the input jacks are wired, there are 5 potential connection lugs, all connected and then grounded to the chassis. Should I use the same connection point as the ground from the input jack to chassis or can I use one of the other grounded lugs on either of the input jacks?
The same exact point where the input jacks are connected to the chassis is where the preamp bus should be connected.

Thanks,
Josh
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Re: Replacing Turret Board Components

Post by mkel2010 »

JMPGuitars wrote:
Thu 05/06/21 8:12 am

The same exact point where the input jacks are connected to the chassis is where the preamp bus should be connected.

Thanks,
Josh
Got it. Thanks.
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