[sdiy] EFM VCO4e troubles...

[jeff brown]

IIRC, the schematic is right, the parts list is wrong.

C1 and C2 are power decoupling caps, 0.01 or 0.1 uF

The only applicable mods I know of are Yves Usson's for the EFM Wildcat 
VCO's. The oscillators are pretty similar (although drawn quite differently) 
and I applied the same changes to my VCO4E's.

The only problem I had was not normalling the "Sync In" to ground. Mine 
would not oscillate without it. Drove me nuts until I noticed it!

Hope this helps,
Jeff

----- Original Message ----- 
From: "nN AAt e e" <timexheater at comcast.net>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Sunday, February 20, 2005 6:36 AM
Subject: [sdiy] EFM VCO4e troubles...


> ok, i know Julian posted about this about this a few weeks ago... but
> now it's my turn to have trouble. this is what i'm getting confused with 
> on
> my first of two VCO4e modules:
>
>    on the parts list, caps #3 to 8 are listed, but the schem has just C 
> 3 -
> 7, and the board has spots for C 1 - 7... it also want's c4 to be a
> polyester cap, but everything that was included with either kit was all
> ceramic... i'm just getting a little confused.
>
>    i was also wondering why the parts list has R39,45,20,44 but only has a
> quantity of 2... i would assume the resistors not included are part of the
> optional heater, but one of the locations is nowhere near it?
>
>    Jay S mentioned that the VCO4e will work with all the documented 
> mods...
> but i haven't been able to find
> anything about fixes on the EFM message board, and the email archive link
> doesn't work... [and no, nothing obvious in the VCO4e pdf either]... if
> anyone has ANY docs that include fixes, i would greatly, greatly, 
> appreciate
> copies of them.
>
>    so unless there is something pretty obvious that i'm looking
> over, i guess i've hit a dead end. thanks for any help... i can't wait to
> finish these up and try them out.
>
> - nathan
>