Where to ground tremolo jack 5G9 Tremolux?

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Phil_S
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Where to ground tremolo jack 5G9 Tremolux?

Post by Phil_S »

I'm unclear. Where is the best place to ground the sleeve of the tremolo foot switch jack in a 5G9 Tremolux?

I'm building it pretty much PTP with three separate filter caps. Since the tremolo is bias modulating and that is all tied into the second filter cap, I want to place it with that filter cap ground. Then, I got a wild hair devil sitting on my shoulder, whispering to me, just ground it directly to the chassis near the jack. I think that devil is just trying to mess me up.

I'm working with three star nodes, one at the ground side of each filter cap, which then all run to a single bolt on the chassis.

(If it's OK with all of you, I'd prefer to avoid the discussion of whether this will work for me. Let's just say, I want to see for myself. I've read many discussions of how to run a ground scheme, even participated. This particular build revealed itself in a particular way, as it is a donor chassis from an organ.)

Where would you ground the jack? Node 2?

I'll post photos when it's done. That's when you can have your fun with me 8)

Thanks.
Firestorm
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Re: Where to ground tremolo jack 5G9 Tremolux?

Post by Firestorm »

I'd be inclined to ground it with the screen supply ground since that is where the oscillator sources its B+. But you may have to experiment. Fender did it right at the jack, and not that Fender were grounding wizards, but they sometimes deliberately grounded things in the "wrong" place to compensate for some other randomness.
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Phil_S
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Re: Where to ground tremolo jack 5G9 Tremolux?

Post by Phil_S »

Yeah, so you agree; also, the devil is Leo himself! What really prompted the question is the Fender layout diagram shows nothing for the sleeve. I figured that meant they were relying on the nut mounted to the panel. Since I'm using a Neutrik/Rean jack, there is plastic at the chassis, I have no choice but to attach a wire at the sleeve connection and place it somewhere. I appreciate your input. If nothing else, it make me feel like I know what I'm doing. As I said, we'll find out when I fire it up. I'm close to being done.
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ChrisM
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Re: Where to ground tremolo jack 5G9 Tremolux?

Post by ChrisM »

Phil_S wrote:Yeah, so you agree; also, the devil is Leo himself! What really prompted the question is the Fender layout diagram shows nothing for the sleeve. I figured that meant they were relying on the nut mounted to the panel. Since I'm using a Neutrik/Rean jack, there is plastic at the chassis, I have no choice but to attach a wire at the sleeve connection and place it somewhere. I appreciate your input. If nothing else, it make me feel like I know what I'm doing. As I said, we'll find out when I fire it up. I'm close to being done.
That's how I'd ground it too. I would add a star/tooth washer though mind you.

This ground point isn't terrible important so I'd tend to ground it with the pre-amp/trem ground wherever that is.
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martin manning
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Re: Where to ground tremolo jack 5G9 Tremolux?

Post by martin manning »

Hi Phil, the footswitch ground 's only purpose is to stop the LFO, so it's probably not critical by any stretch. The most direct place to get that done, though, is at the LFO cathode resistor's ground end.
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Phil_S
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Re: Where to ground tremolo jack 5G9 Tremolux?

Post by Phil_S »

Hi Martin,
I was waffling between the cathode and the - end of the cap. The cathode is going to the same cap. I opted to go to the cap. We'll see how it goes! Thanks.
Phil
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