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Re: Diezel VH4 Pedal

PostPosted: 06 Nov 2017, 17:57
by caspercody
What do you use to attach the voltage regulator to the board? To help heat sink it.

Re: Diezel VH4 Pedal

PostPosted: 06 Nov 2017, 23:38
by bmxguitarsbmx
caspercody wrote:What do you use to attach the voltage regulator to the board? To help heat sink it.


To sink what heat? Not being snotty, but the TO-220 package could easily be dropped to a TO-92 package and use only air cooling:

https://www.mouser.com/ProductDetail/ON ... %2fRhHA%3d

^100mA TO-92 12V linear regulator

Re: Diezel VH4 Pedal

PostPosted: 07 Nov 2017, 16:07
by caspercody
I ordered a kit, and it came with the LM2940CT-12.

Re: Diezel VH4 Pedal

PostPosted: 08 Nov 2017, 17:25
by Svullgo
First I wanna say thanks to all you heroes who put down a lot of time in this community and sharing your results and knowledge!
You have helped me a lot in learning and understanding the electronics of pedals!

I have built this after Alex Vero at tagboardeffects and everything works. (I needed to up the the 47p capacitor to 560p as reichi suggested to get rid of the oscillation/feedback on higher gain levels)
I wonder if the presence and resonance works as the original (which I never have tested)
The presence lowers the the perceived volume a lot when turned down and resonance feels like its to much in the lower midrange. (but thats what Bajaman on page 4 says that they should do but have anyone have had the opportunity to A/B-test it with an original?)

Re: Diezel VH4 Pedal

PostPosted: 09 Nov 2017, 18:44
by Daza
I set the bass version, and I also have oscillation with high gain (around 12 o'clock) I'll see if it goes down changing the 47p

Re: Diezel VH4 Pedal

PostPosted: 09 Nov 2017, 18:49
by Daza
Daza wrote:I set the bass version, and I also have oscillation with high gain (around 12 o'clock) I'll see if it goes down changing the 47p



I set the bajaman version, and I also have oscillation with high gain (around 12 o'clock) I'll see if it goes down changing the 47p

Re: Diezel VH4 Pedal

PostPosted: 09 Nov 2017, 20:02
by brejna
It does, but pedal sound muddier...

Re: Diezel VH4 Pedal

PostPosted: 09 Nov 2017, 21:37
by bmxguitarsbmx
The real way to tame oscillation is to examine the layout. IMO

Re: Diezel VH4 Pedal

PostPosted: 10 Nov 2017, 01:23
by Daza
It would not be good muddy sound.
I put shielded cable and it improved a bit. Increasing the depth increases the oscillation considerably

Re: Diezel VH4 Pedal

PostPosted: 10 Nov 2017, 03:06
by Daza
Will you have a problem with the input impedance the scheme?
I put a buffer before the pedal as recommended by Brejna and the oscillations disappeared!

Re: Diezel VH4 Pedal

PostPosted: 10 Nov 2017, 06:07
by J0K3RX
I wouldn't bother with shielding the output... I would shield the input and definitly the gain pot! Poke around with an audio probe and it should lead you right to the source of the oscillation...

Re: Diezel VH4 Pedal

PostPosted: 11 Nov 2017, 00:07
by bmxguitarsbmx
I wish I could attribute this quote pertaining to pcb layout:

"rarely will stray capacitance to ground cause the problems that stray capacitance between any other traces have".

Shield it up! Proximity/phase is also worth considering.

Re: Diezel VH4 Pedal

PostPosted: 12 Nov 2017, 18:24
by sego91
Im gonna try to replace the 7660s with another IC to eliminate the oscilation and squeel, maybe a 1054 im gonna check it out .