Search found 72 matches

by Jacob Hunt
Tue Jun 10, 2014 8:36 pm
Forum: HELP!
Topic: OB-Xa - all EGs gone bad?
Replies: 114
Views: 17009

Re: OB-Xa - all EGs gone bad?

I had alot of similar problems with the connecting ribbon cables myself. Sometimes the envelopes would be completely different between boards. I also one time had a slight difference between them that was fixed by calibrating the power supply. The pot board 4051's have been pretty problematic too. T...
by Jacob Hunt
Mon Jun 09, 2014 6:49 pm
Forum: HELP!
Topic: Moog Source Bad Oscillator
Replies: 5
Views: 1666

Re: Moog Source Bad Oscillator

Well, replacing the transistors, diodes, and the 4558 in the temp. And osc. 1 circuit has greatly improved things. Osc. 1 comes in in seconds rather than a half hour, so after a normal warmup time, it's good to go :D
by Jacob Hunt
Sun Jun 08, 2014 6:19 am
Forum: Gear Services & Other Goods
Topic: Wanted: OB-Xa bender pot
Replies: 1
Views: 775

Wanted: OB-Xa bender pot

The old bender in mine is absolutely no good anymore. I got a new pot from radioshack, and the shaft would wobble bad and make the pitch go out everytime I looked at it. Do I need a different type? Does somebody have one they know will work?
by Jacob Hunt
Wed Jun 04, 2014 6:36 pm
Forum: HELP!
Topic: Moog Source Bad Oscillator
Replies: 5
Views: 1666

Re: Moog Source Bad Oscillator

Touching or blowing on any of the temperature circuit parts makes the problem come back, after it takes it's warm up time. This doesn't happen for osc. 2. I don't know much about the temperature circuit, but something must be bad there, just don't know how to tell..
by Jacob Hunt
Wed Jun 04, 2014 4:36 am
Forum: HELP!
Topic: Moog Source Bad Oscillator
Replies: 5
Views: 1666

Re: Moog Source Bad Oscillator

I have, with no luck. I turned the osc. 1 temp trimmer, and it came to pitch, and so fooled around with some of the temp. circuit parts. It seems like it may be better now, I'll wait and see how it does over time.
by Jacob Hunt
Tue Jun 03, 2014 10:24 pm
Forum: HELP!
Topic: Moog Source Bad Oscillator
Replies: 5
Views: 1666

Re: Moog Source Bad Oscillator

Still no luck :cry:
Does anybody have an idea what to look at? Is it possibly a cv issue?
by Jacob Hunt
Mon May 19, 2014 8:40 pm
Forum: HELP!
Topic: Moog Source Bad Oscillator
Replies: 5
Views: 1666

Moog Source Bad Oscillator

Oscillator 1 on my source has quit on me. Before it went completely out it would fail to switch to triangle wave, now it doesn't make any sound for a while. After warming up for a long time, it makes a very high pitch FM type sound and slowly comes down closer to the note it should be, but is pretty...
by Jacob Hunt
Fri Mar 28, 2014 3:15 am
Forum: General Synthesizers
Topic: anyone else like wurly/rhodes/clavinet/organ here?
Replies: 40
Views: 9268

Re: anyone else like wurly/rhodes/clavinet/organ here?

Synthesizers are great, but I could never let go of my Vox continental and rhodes bass, ever. For any reason. I also have a rhodes piano (saved it from the high school band closet) and a cp-70, and love them. The rhodes definitely won't be leaving anytime soon, but the cp-70 sure does eat up alot of...
by Jacob Hunt
Fri Feb 21, 2014 6:25 am
Forum: The Listening Lounge
Topic: Free analog and modular synth music
Replies: 2
Views: 827

Re: Free analog and modular synth music

Virtual values sounded great, very nice, but strangely funky atmosphere.
by Jacob Hunt
Mon Feb 17, 2014 9:04 pm
Forum: HELP!
Topic: Oberheim OBXA Not Saving After Shut Down
Replies: 7
Views: 8608

Re: Oberheim OBXA Not Saving After Shut Down

I have an OB-Xa that did the same thing, even after replacing the battery. My Oberheim DMX did it too. Both of them ended up just needing some diodes replaced in the battery circuit, and maybe a couple caps on the OB-Xa, I believe it had a tantalum in it, and it's always safer to replace those when ...
by Jacob Hunt
Fri Sep 27, 2013 8:12 pm
Forum: HELP!
Topic: Another Ob-Xa Issue
Replies: 5
Views: 829

Re: Another Ob-Xa Issue

Turns out it was the 4051 itself. duh. Glad that's over with, I was getting pretty scared.
by Jacob Hunt
Fri Sep 27, 2013 6:37 pm
Forum: HELP!
Topic: Another Ob-Xa Issue
Replies: 5
Views: 829

Re: Another Ob-Xa Issue

Common sense prevailed, and I checked the voltage verification steps. IC #145 (another 4051) on the upper board is not recieving a proper 5.6v, but a not so healthy 2v. Now to track down the culprit(s).
by Jacob Hunt
Fri Sep 27, 2013 6:18 am
Forum: HELP!
Topic: Oberheim OB-Xa Lower Board Issue
Replies: 3
Views: 742

Re: Oberheim OB-Xa Lower Board Issue

Thanks, but I probably won't be able to afford a whole new card, but I know I'll need at least one CEM for this card, the 3310. But now a whole new problem has come up, making the entire synth almost completely useless for now.
by Jacob Hunt
Thu Sep 26, 2013 10:57 pm
Forum: HELP!
Topic: Another Ob-Xa Issue
Replies: 5
Views: 829

Re: Another Ob-Xa Issue

It seems it is related to key CV maybe. Those notes' boards that go wacky are not getting past 3 volts for the key CV input when I go higher up the keyboard. Strangely though the top boards are getting proper voltage up until past 4 volts. The schematic has key cv as coming out of a 4051 (U47) on th...
by Jacob Hunt
Thu Sep 26, 2013 8:11 pm
Forum: HELP!
Topic: Another Ob-Xa Issue
Replies: 5
Views: 829

Re: Another Ob-Xa Issue

Turns out the bottom boards also start to get crazy after the 3rd B key. They're not distorted badly like the top ones, but they sure don't sound right at all. Thanks in advance to anybody who may have some insight.