Search found 22 matches

by e_just
Mon Mar 16, 2015 5:10 pm
Forum: Moog Music General Topics Forum
Topic: Moog/Realistic MG-1 Mod Guide
Replies: 41
Views: 69993

Re: Moog/Realistic MG-1 Mod Guide

One thing I failed to mention is that I installed a new 50KA peat emph slide pot from Syntaur. I wonder is the pot is bad or possibly the wrong value.
by e_just
Mon Mar 16, 2015 3:59 pm
Forum: Moog Music General Topics Forum
Topic: Moog/Realistic MG-1 Mod Guide
Replies: 41
Views: 69993

Re: Moog/Realistic MG-1 Mod Guide

I did not, how difficult is it to recalibrate?
by e_just
Mon Mar 16, 2015 3:33 pm
Forum: Moog Music General Topics Forum
Topic: Moog/Realistic MG-1 Mod Guide
Replies: 41
Views: 69993

Re: Moog/Realistic MG-1 Mod Guide

Has anybody else compleated the minimoog filter mod? After instaling this mod, the peak emphasis does nothing untill it is turned up to about 90 %, then quickly goes into self oscilation. Im not sure if this is normal.
by e_just
Fri Feb 20, 2015 9:59 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

The problem ended up being a bad IC9. I replaced it and now the filter is back to normal, I think... Now the audio is distorted. The distortion effects all audio, not just the 2 OSCS. I guess I now have a bad VCA? It never ends :?
by e_just
Tue Feb 17, 2015 9:03 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

You can rule out the slide pots by de soldering them and using a different pot in their place. You could try jumping the emphasis pot with a wire/clip to see if bypassing it entirely gives you the effect you would normally have when fully up. I would verify voltages on all the ICs and transistors i...
by e_just
Sun Feb 15, 2015 10:47 am
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

Hey Gang I am still having trouble with the MG and wanted to post an update. First, here is a new video of the problem. m As you will notice, the filter only allows audio through it when the cutoff slider is towards the middle. The peak emphasis has some but very little effect, you can't really hear...
by e_just
Sat Feb 14, 2015 8:41 pm
Forum: Moog Music General Topics Forum
Topic: Moog/Realistic MG-1 Mod Guide
Replies: 41
Views: 69993

Re: Moog/Realistic MG-1 Mod Guide

Yeah, already shipped but no big deal. I need to place another order with them anyway because I forgot a few things so its all good :mrgreen:
by e_just
Sat Feb 14, 2015 5:17 pm
Forum: Moog Music General Topics Forum
Topic: Moog/Realistic MG-1 Mod Guide
Replies: 41
Views: 69993

Re: Moog/Realistic MG-1 Mod Guide

**I'm posting this early. Over the next couple weeks I'll be adding more pictures and details. I could use any help I can get for this work in progress. Please correct any errors, add any additional ideas, or any other way to contribute. It's a pretty large project!** In order to do this, you will ...
by e_just
Wed Feb 04, 2015 11:27 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

There are 6 connectors on the bottom pcb. If you are talking about the four that are close together (next to the power section on the left), those are the power connectors. It wouldn't make any sense that your synth would work without those connectors. Maybe the caps held enough of a charge for a m...
by e_just
Wed Feb 04, 2015 11:26 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

Well, I'm making some progress! After studying the service manual I decided to test the voltage of some of the ICs. I noticed that IC 10 seemed to be dead. Since I had a few 353 ICs left from a previous MG1 project I soldered a new one in. That seemed to fix the muffled filter problem but I am still...
by e_just
Tue Feb 03, 2015 11:40 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

I tried reversing the mod but it didn't fix the problem. One thing of interest to note is that after I reversed the mod, I powered up forgetting to connect the four plastic connecters to the bottom board. I thought for a second that everything was back to normal because the synth made a normal (not ...
by e_just
Tue Feb 03, 2015 10:03 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

Thanks for the walk through. Everything looks good so far. I measured +12. / -15.4
by e_just
Tue Feb 03, 2015 9:20 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

I have limited experience in the testing area but I do have a multimeter handy. Can you walk me through this? I really appreciate your help.
by e_just
Tue Feb 03, 2015 8:49 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

http://youtu.be/vS6ij5QGNQ4

Here is the video. Not the best quality but I think it will do. Notice how the filter makes a poping sound. Any advice?
by e_just
Tue Feb 03, 2015 3:02 pm
Forum: Moog Music General Topics Forum
Topic: MG1 Filter Problem
Replies: 23
Views: 1099

Re: MG1 Filter Problem

I already resoldered those pins and removed, disassembled, cleaned, reassembled and resoldered both the cutoff and res sliders. I am starting to wonder if some black gunk that I have missed is shorting something out inside. As for the filter slider, it works but the range of the cutoff is way off. I...