Univox Uni-Comp Model CO-105 schematic and board pics  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...

Univox Uni-Comp Model CO-105 schematic and board pics  [schematic]

Postby Bside2234 » 02 Apr 2011, 20:06

Just picked this up and couldn't find any info about it here so I thought I'd add it.
IMG_3230sm.jpg
IMG_3229sm.jpg
IMG_3227sm.jpg
IMG_3228sm.jpg
Uni-Compcomponents.jpg
You do not have the required permissions to view the files attached to this post.

For this message the author Bside2234 has received thanks: 9
bmxguitarsbmx (24 Jan 2018, 03:16), borislavgajic (02 Apr 2011, 22:59), Dan N (06 Apr 2011, 02:14), jb351 (02 Apr 2011, 20:12), jonescg (05 Apr 2017, 23:26), modman (23 Jan 2018, 23:40), Nocentelli (02 Apr 2011, 21:37), sinner (02 Apr 2011, 21:07), Steven_M (03 Apr 2011, 00:10)
Bside2234
Solder Soldier
 
Posts: 219
Joined: 30 Jul 2007, 20:35
Location: Kennewick, WA
Has thanked: 5 times
Have thanks: 52 times

Re: Univox Uni-Comp Model CO-105 schematic and board pics

Postby reddesert » 22 Jan 2018, 07:33

Great pictures and work.

There is a 33 uf cap on the board that is not in the schematic. This should go from the collector of the transistor (+ end of the cap) to the emitter / ground.

There are several schematics floating around for the Uni-Comp and they're all a little different.
1. Bside2234's schematic above.
2. one at http://www.davidmorrin.com/home/trouble/troubleeffects/univox-uni-comp. Here he has a 3.3K and 1K resistor in parallel from +9V to the vactrol. This doesn't make sense and I suspect that one of them is supposed to be a 10 uf capacitor.
3. one for the seemingly identical Melos Comp at http://files.effectsdatabase.com/docs/files/melos_minicomp_schematics.jpg. This has a 2.2K resistor and 10uf cap from +9V to the vactrol.

Finally, there are unverified vero layouts at http://tagboardeffects.blogspot.com/2017/03/univox-uni-comp.html, for the David Morrin and Melos schematics (but the comp pot is backwards). And there's a DIYSB thread at http://www.diystompboxes.com/smfforum/index.php?topic=119185.msg1111474. The tagboardeffects gang and Mark Hammer on DIYSB appear to agree that the rectifying diode D1 should be a germanium or Schottky. Not sure about the clipping diodes D2 and D3.

I built one with D1 = BAT46; D2, D3 = silicon, using a LED+LDR in place of the vactrol, after cleaning up the various errors, and it does work.

For this message the author reddesert has received thanks: 2
Manfred (28 Jan 2018, 23:50), modman (23 Jan 2018, 23:41)
reddesert
 
Posts: 11
Joined: 03 Jun 2016, 18:01
Has thanked: 6 times
Have thanks: 12 times

Re: Univox Uni-Comp Model CO-105 schematic and board pics

Postby Manfred » 28 Jan 2018, 23:48

I have created a PCB layout clone for all vintage fan.
Layout:
Univox Uni CompLayout.JPG

Ready to print files, print as original size:
Univox Uni Comp PCB Solder.pdf

Univox Uni Comp PCB Components.pdf

SprintLayout6 file:
UnivoxSPL6.zip
You do not have the required permissions to view the files attached to this post.

For this message the author Manfred has received thanks:
reddesert (31 Jan 2018, 21:21)
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times


Return to Vintage Stompbox Corner ( ... - 1975)

Who is online

Users browsing this forum: No registered users and 4 guests