majmoog at synthfool.com
Mon Mar 2 11:04:20 CET 1998
I've just finished assembly on my first ASM-1. (Sorry it took so long to
First off, I'm very happy to say that it all worked upon it's first power
However, if some of you already experienced ASM-1 folks don't mind , I have
a few questions to ask.... :)
First a descriptive-
My ASM-1 uses 2N3904s (instead of the MAT02) and KRL 1.87K 3% tempcos
(similar to Arp).
The pairs and tempco are bonded to each other for each VCO.
The FETS are 2N4391's.
I didn't have any 30pf caps for the VCF or 18pf caps for the VCO's.
Instead, I used 33pf caps for both.
It's about 80% 1% metal film resistors (the vco summers and other criticals
are 1%), but the rest are 5% carbon film.
Standard sockets (not machined) were used. (Generally, I use machined but
this is a LOT of IC's :)
Board is wholly defluxed (and gorgeous!)
My current draw is 103ma (+15volts) and 118ma (-15volts).
(Strange for me to see the negative rail drawing more than the positive.)
Everything appears to work fine. Waveforms are of great shape, noise is
good, VCF works, etc.
The VCO's seem very stable too. :)
I haven't really hooked up pots and used or played the unit.
I've just gone through each "module" functionally.
Any thoughts / ideas / tips on the above? Bad choice on caps, resistors or
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