Sudden increase in B+ voltage

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Re: Sudden increase in B+ voltage

Post by Bieworm »

Yes correct. But Josh advises to put them after the filter cap. This means you have to put in a solder terminal. Wire from rectifier to the 1st filter cap - zeners between 1st filter cap and solder terminal - dropping resistor from terminal to 2nd filter cap. Branch off the wire to the prim side CT of the OT at the terminal, after the zeners and before the dropping resistor… look at the downloads section for a layout on the Tremolo TMB amp…
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Re: Sudden increase in B+ voltage

Post by riley0 »

Due to PCB layout, more trouble-free going before 1st filter cap, plus the ECL82 plates need to come down.
On orders few different 1N53 values.
Will report back soon!
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Re: Sudden increase in B+ voltage

Post by Bieworm »

riley0 wrote:
Wed 02/22/23 3:43 pm
Due to PCB layout, more trouble-free going before 1st filter cap, plus the ECL82 plates need to come down.
On orders few different 1N53 values.
Will report back soon!
The plates will come down more accurately when wired as described above. They connect after the zeners after the 1st filter. But either way is good… my way isn’t as accurate as Josh pointed out
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Re: Sudden increase in B+ voltage

Post by riley0 »

Just a quick update - Managed placing zeners after 1st filter with success.

Amazing results, dropped 30v.
Do you guys believe it makes any changes to feel/tone? I can't make judgment just yet, need to play through it for a while...
But what an easy mod anyone can make..
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Re: Sudden increase in B+ voltage

Post by JMPGuitars »

riley0 wrote:
Sat 02/25/23 10:03 am
Just a quick update - Managed placing zeners after 1st filter with success.

Amazing results, dropped 30v.
Do you guys believe it makes any changes to feel/tone? I can't make judgment just yet, need to play through it for a while...
But what an easy mod anyone can make..
Yes, the voltage can make a big difference in feel and tone. Not the Zeners themselves, but the voltages. Circuits are typically designed with voltages in mind, and if they're far out of spec, then the amp isn't going to sound or respond as expected. If the voltages now are where they were before when you used the amp previously, then you shouldn't notice much of a difference, if any at all.
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Re: Sudden increase in B+ voltage

Post by Bieworm »

FWIW in sequence of your PM , nowadays I order my turretboard material directly from kunststofplaten.nl
Those are large boards like 1m x 1m. They’re the greenish type. Cost comes down to 50% of the precut material. But that’s if you build a lot of amps like me😁
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