Don't buy the 3080s or any parts for that matter on eBay. See if Jameco or some reputable seller still has any. If all else fails, I have a high quality replacement submodule on my site...

Assuming you can't scope out the filter in a test circuit, you might consider testing the JFETs out of circuit before you try replacing the OTAs.

Check out my video:



LM301 is the most common failure in them. I'm working on 4 Odysseys in parallel now, two have the 4023 and both of them are bad and need to be excavated and repaired. You won't need to buy a replacement clone.

Unless it's a Chroma where you can configure it to have 16 voices with 1 oscillator each or 8 voices with 2 oscillators each.

Since original Omni 2s are difficult to come by are there any modern hardware alternatives to the Omni 2? I've got a bunch of Omni 2's, and I make them reliable! If you're interested in the real deal, hit me up on my website. Oh? can't you find them under "Synthesizers" on your site... I've not got...

unknownid wrote:Since original Omni 2s are difficult to come by are there any modern hardware alternatives to the Omni 2?

I've got a bunch of Omni 2's, and I make them reliable! If you're interested in the real deal, hit me up on my website.

You'll probably need an oscilloscope to get anywhere with it.

I bought the one listed at 595 OBO and have one other I've been waiting to get around to restoring. It's not working right and needs a restoration. There are really 3 values... Parts/repair like the comps you were shown. Used/100% working, and restored. I'd expect a used/working Explorer I to be aro...

MPS5172 is the same as 2N5172 which is still available. 2N3904 should also work but it has a different pinout (EBC vs ECB).

"Inside the World's Worst Juno 106" photo album on facebook

https://www.facebook.com/media/set/?set ... 705&type=3

Good for who? The buyer or the seller?

In general, I find that when a trimmer gets old, the carbon track gets damaged (indented, maybe?) where the wiper has been parked for years. Then you go to make a slight adjustment and you have erratic behavior close to the old parking spot of the wiper.

I'd recommend reading the active filter cookbook by Don Lancaster. A great book that covers active (transistor-based) filters in detail.

First I'd check the resonance control voltage, ahead of R349 (33k resistor going to pin 9 of the curtis chip) and see if it moves with your resonance knob and matches the voltage on the other voices. Just to be sure. Next you might try swapping U305 and U307 with a neighboring voice. Of everything i...