Building the WHAT compressor

[Kir_For_Pleasure]

Someone with a more completed bom or sketches to share ?
Also photos of stuffed boards are intresting.

 

[mfdu]

was that for the fabio pcb? i'm sure there is a BOM at the start of this thread. i had a look for a BOM. from memory it certainly wasn't comprehensive - i had to use my brain more than i like.
i was sure there was one at the start of this thread?!

http://home.alphalink.com.au/~mfdu/opto.html

aaah - here we go (via link on my page to DIY Pill - there is more. schematics and stuff.)
http://www.thediypill.phx.com.br/joecheep_bom.txt

mfdu

 

[Kir_For_Pleasure]

Thats great !!!
Im not dumb but this project was very hard for me in the beggining, but feels like i have the right tools to sucess now, and the picture is one of them :grin:
The link to the bom on fabios page are not the what comp.

 

[mfdu]

this should stay live for a couple of yars, and will hopefully help out!

http://home.alphalink.com.au/~mfdu/files/fabios_what.zip

(the what, and melcor doa's)

chris

 

[Kir_For_Pleasure]

You are the man !!!

 

[Kir_For_Pleasure]

I dont find a schematic or partlist for Fabios Melcor boards Rev1, i found a schematic on the thediypill.phx.com.br but it dosent display which version it is, someone knows ?

 

[Kir_For_Pleasure]

Done ! up for testing and audio goes throu but it dosent compress ? With full gain you can hear a little diffrence but not much.

Mfdu i think you had something like this, what was wrong with yours ? Have melcors and oep traffo, all the pots and the filter not april.

 

[Kir_For_Pleasure]

 

[Kir_For_Pleasure]

I dont think i have power to the board, maybe the toroid is broken, if i measure at the melcor boards 0 -v +v G i dont get any values at all, completly dead ! before the toroid all is fine 233V

 

[3nity]

but you said you were having audio through it dont you?
Look at the sidechain if its not compressing!

Jorge.

 

[Kir_For_Pleasure]

I have audio throu even if i not power it up ?

 

[StephenGiles]

Forgive me for saying so, but one slip on the keyboard during the word through, pronounced throo, and it turns into trough, pronounced troff - a container that horses drink out of! Folks learning English must have one hell of a time with words containing "ough"!!

Might I suggest that you disconnect the power supply and connect a couple of PP3 batteries to test the various sections of the compressor?

 

[Kir_For_Pleasure]

 

[3nity]

What i like in DIY is that we all come from all over the world! see?
For some of us English is not our first language so you should be a bit tolerant here please!

Pero si quieres hablar espanol, perfecto ( but if you know spanish perfect)

:green:

 

[3nity]

Check the toroidal secondaries please (AC) make sure you have a 0V and the 2 remaining leads have 15V each aprox.... if okay check the psu!!

First things first!

 

[Kir_For_Pleasure]

AC
Red Orange 0,5v
Black yellow 0,3V


AC
Orange 10,34 V
Black 10,56 V
Yellow 10,54 V
Red 14,68 V

This values is measured without ground ?

 

[StephenGiles]

[quote author="3nity"]What i like in DIY is that we all come from all over the world! see?
For some of us English is not our first language so you should be a bit tolerant here please!

Pero si quieres hablar espanol, perfecto ( but if you know spanish perfect)

:green:[/quote]

Hay que tener corazón!

 

[Kir_For_Pleasure]

with batteries voltage works. Need new toroidal !

 

[mfdu]

you've of course checked your voltage trimpots, huh?

when i first built it, i didn't realise but i had +12v / -3v due to not checking the trimpot. and here was me thinking "gee, there's a bit of distortion" . . .

also, i tested and set up my units using the IC opamps. once i knew it was working, i changed over to melcors . . . one less possible are of error . . .

cheers

ps. i have these with adjustable ratio / threashold / output. i love them on bass, on vocals, and to squish room mics.

chris.

 

[flintan]

[quote author="Kir_For_Pleasure"]with batteries voltage works. Need new toroidal ![/quote]

I would check the toroid you already have first. If it's bad or if some lead colour is wrong or just to trace down what is wrong..

1. Make shure wich leads are in the same windings (dc resistance measuring).
2. Then try connect two from different windings and apply mains voltage.
3. Measure voltage between the centertap and end-leads, should be in the area of rated voltage. Then measure between the both end-leads, if it's 0V then you have to connect it the other way. If it's approx 2x rated voltage then you're good!

Just watch out so you don't short the windings!! And to be on the safe side, use a fuse on the primary.

Then you just continue the same way following trough the PSU circuit to spot where the error might be..