New TMB w/reverb Build

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foreverstrung
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New TMB w/reverb Build

Post by foreverstrung »

First pic of the progress so far.
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Re: New TMB w/reverb Build

Post by foreverstrung »

Wired the pots in tonight.
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Re: New TMB w/reverb Build

Post by foreverstrung »

So, shielded wire question. Does this pic show the correct way to use the shielded wire?
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Re: New TMB w/reverb Build

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Well... the shielding of the shielded wire should only be connected at one end. Te other end should be clipped and sealed off with heatshrink. I can't see if you did that because you only show one end of the wire.
For good practice and result it's best to connect the shield at the input ground, not at the tube socket side.

And if that's V1 and the resistor shown is the grid stopper of V1a ( input tube 1st amplification stage).. then you should remove that 2M resistor and put a 10k instead.
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Re: New TMB w/reverb Build

Post by foreverstrung »

Here's a better pic. The V1 resistor is 10K, no 2M
At the input jack, you can't see it, but only the center wire is attached and the braided wire is cut back and you can see the heat shrink.
That's a 1M resistor on the input jack
so, if I understood you correctly, in this application, the best end of the shielded wire being grounded is on the input jack side?
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Re: New TMB w/reverb Build

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foreverstrung wrote: ↑
Wed 11/16/22 4:59 pm
Here's a better pic. The V1 resistor is 10K, no 2M
At the input jack, you can't see it, but only the center wire is attached and the braided wire is cut back and you can see the heat shrink.
That's a 1M resistor on the input jack
so, if I understood you correctly, in this application, the best end of the shielded wire being grounded is on the input jack side?
Yes, the input is the noisiest side, and that's where it should be tackled.

And 10k? That resistor is marked 1934, so 1930000 ohms. Thats 1.93 mega ohms in my book. Vishay/Dale would mark a 10k as 1002
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Re: New TMB w/reverb Build

Post by JMPGuitars »

Bieworm wrote: ↑
Wed 11/16/22 11:30 pm
And 10k? That resistor is marked 1934, so 1930000 ohms. Thats 1.93 mega ohms in my book. Vishay/Dale would mark a 10k as 1002
Your book is missing a few pages. πŸ˜‰πŸ˜‰

Those are 10K CMF resistors, which have the actual value printed on them:
10k-1934.jpg

Thanks,
Josh
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Re: New TMB w/reverb Build

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JMPGuitars wrote: ↑
Thu 11/17/22 9:44 am
Bieworm wrote: ↑
Wed 11/16/22 11:30 pm
And 10k? That resistor is marked 1934, so 1930000 ohms. Thats 1.93 mega ohms in my book. Vishay/Dale would mark a 10k as 1002
Your book is missing a few pages. πŸ˜‰πŸ˜‰

Those are 10K CMF resistors, which have the actual value printed on them:

10k-1934.jpg


Thanks,
Josh
How weird ...
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Re: New TMB w/reverb Build

Post by JMPGuitars »

Bieworm wrote: ↑
Thu 11/17/22 9:56 am
How weird ...
Yeah, they're made my Dale also. I never paid attention to those numbers. EDIT: I just looked, it appears those are 4 digit date codes (YYWW): https://www.vishay.com/docs/31018/cmfind.pdf

The other numbers you referenced (which aren't on those) is fairly common with other brands too.
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Re: New TMB w/reverb Build

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JMPGuitars wrote: ↑
Thu 11/17/22 12:53 pm
Bieworm wrote: ↑
Thu 11/17/22 9:56 am
How weird ...
Yeah, they're made my Dale also. I never paid attention to those numbers. EDIT: I just looked, it appears those are 4 digit date codes (YYWW): https://www.vishay.com/docs/31018/cmfind.pdf

The other numbers you referenced (which aren't on those) is fairly common with other brands too.
I only used the dales one time. I usually buy the banded stuff. The dales over here are only 0.4W and I use mostly 1 or 2W. Dales cost way more than anything else too
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Re: New TMB w/reverb Build

Post by foreverstrung »

Re-doo'd.
Re-read grounding schemes and Josh's workbook. It's all right there.
Shrink tube up high for pic. Slid it down and wrapped ground connection after.
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Re: New TMB w/reverb Build

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foreverstrung wrote: ↑
Thu 11/17/22 2:03 pm
Re-doo'd.
Re-read grounding schemes and Josh's workbook. It's all right there.
Shrink tube up high for pic. Slid it down and wrapped ground connection after.
Looks like you forgot the ground wire to the future turret board?
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Re: New TMB w/reverb Build

Post by foreverstrung »

Bieworm wrote: ↑
Thu 11/17/22 4:00 pm
foreverstrung wrote: ↑
Thu 11/17/22 2:03 pm
Re-doo'd.
Re-read grounding schemes and Josh's workbook. It's all right there.
Shrink tube up high for pic. Slid it down and wrapped ground connection after.
Looks like you forgot the ground wire to the future turret board?
No, this is it right here. Just sitting on top of this pot.
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Re: New TMB w/reverb Build

Post by JMPGuitars »

Bieworm wrote: ↑
Thu 11/17/22 1:14 pm
I only used the dales one time. I usually buy the banded stuff. The dales over here are only 0.4W and I use mostly 1 or 2W. Dales cost way more than anything else too
'Murica! We gots the bigun resistors! 🀣🀣🀣
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Re: New TMB w/reverb Build

Post by JMPGuitars »

foreverstrung wrote: ↑
Thu 11/17/22 5:42 pm
No, this is it right here. Just sitting on top of this pot.
It's an illusion, partly caused by the smaller size image. If you don't look closely, it looks connected to the pots. But I knew you got it right anyway, since you got all the docs. πŸ˜‰
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Re: New TMB w/reverb Build

Post by Bieworm »

JMPGuitars wrote: ↑
Thu 11/17/22 7:46 pm
foreverstrung wrote: ↑
Thu 11/17/22 5:42 pm
No, this is it right here. Just sitting on top of this pot.
It's an illusion, partly caused by the smaller size image. If you don't look closely, it looks connected to the pots. But I knew you got it right anyway, since you got all the docs. πŸ˜‰
My bad... you attach the grounds from the pots directly to the ground buss.
I usually add an extra ground buss at the pots and connect the end of that buss to the input ground.
input grounds.png
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Re: New TMB w/reverb Build

Post by JMPGuitars »

Bieworm wrote: ↑
Fri 11/18/22 3:35 am
My bad... you attach the grounds from the pots directly to the ground buss.
I usually add an extra ground buss at the pots and connect the end of that buss to the input ground.
Don't forget he's got the PCB, so it's all labeled and done on the board.
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Re: New TMB w/reverb Build

Post by foreverstrung »

I'm having a hard time understanding the footswitch and manual switch(s) for trem and reverb. Is it smart to add 2 switches? 1 switch?, or just use pedal? If I do just use the pedal and no switches, I'm confused on how to hook this input jack up. It's not real clear.
To clarify, I'd really like to add both manual switches, but I'm confused on how to wire this up.
Recommended switches would be appreciated too.
I understand that this will be linked in after running the amp through a preliminary run and voltage tests.
Thx
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Re: New TMB w/reverb Build

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foreverstrung wrote: ↑
Sat 11/19/22 10:36 am
I'm having a hard time understanding the footswitch and manual switch(s) for trem and reverb. Is it smart to add 2 switches? 1 switch?, or just use pedal? If I do just use the pedal and no switches, I'm confused on how to hook this input jack up. It's not real clear.
To clarify, I'd really like to add both manual switches, but I'm confused on how to wire this up.
Recommended switches would be appreciated too.
I understand that this will be linked in after running the amp through a preliminary run and voltage tests.
Thx
I never make my reverb switchable. It's just as easy to dial the reverb knob to zero when you don't want reverb.
The tremolo gets a footswitch from me. I don't see the point of having a toggie switch as well.. just use the footswitch.
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Re: New TMB w/reverb Build

Post by JMPGuitars »

foreverstrung wrote: ↑
Sat 11/19/22 10:36 am
I'm having a hard time understanding the footswitch and manual switch(s) for trem and reverb. Is it smart to add 2 switches? 1 switch?, or just use pedal? If I do just use the pedal and no switches, I'm confused on how to hook this input jack up. It's not real clear.
To clarify, I'd really like to add both manual switches, but I'm confused on how to wire this up.
Recommended switches would be appreciated too.
I understand that this will be linked in after running the amp through a preliminary run and voltage tests.
Thx
The two switches in the chassis are for the tremolo. One is to turn the tremolo on and off, and the other is to change the speed range for the tremolo. Follow the layout for those switches. If something isn't clear, let me know, and I can help with that.

The footswitch is setup only to turn the tremolo on/off, and to turn the reverb on/off. I would ignore the footswitch itself until the amp is complete. Just wire the footswitch jack per the layout.

Thanks,
Josh
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