Ensoniq SQ2 trouble shooting advice needed

[Jesse Pearson]

Right, I'm starting to see that I have a short that is dragging down the PSU and that's what I have to find right at this point. I'm studying on the subject...

[Jesse Pearson]

Yes, that big Tantalum cap tested shorted with my ohm meter and did not have the raising ohms to OL while in circuit. My BK ESR/DCR meter showed it had low...

[Jesse Pearson]

GI, that big tantalum cap has .005 ohms in circuit. I guess I should pull one leg out of circuit to see if it still has the same reading. There are a handful...

[Jesse Pearson]

I was having a hard time finding these caps because I wasn't using the right terminology nor did I know how to read the values on them. I went to Amplifier...

[Jesse Pearson]

Thanks Markusbass for the advice. Could you please give me a link for buying some of those caps if possible, because I can't seem to find one. Since I'm so...

[Jesse Pearson]

Thanks guys...Yes Dude, there is a multiplexer that is too hot to touch located at U9 on the main board (MC14051B). It's temp under power on the board is...

[Jesse Pearson]

Anybody familiar with these little yellow components on the main board. I thought they were ceramic capacitors because they have a .i.e. "C89" silk...

[Jesse Pearson]

Thanks Dude, that's Nicklaus from Germany and one of the guys I spoke with. He was kind enough to send me an HD pic of the section of main board I needed...

[Jesse Pearson]

Cool stories...what surprises me about the SQ line, is that there is still no real resource collective on line that specializes in trouble shooting these...

[Jesse Pearson]

Cool, thanks Dude...

[Jesse Pearson]

Thanks Dude...yes, the 18.12 volts is supposed to be + and - voltages but since it is ac voltage coming off the power supply, my meter is giving me the same...

[Jesse Pearson]

Here is the main board that blew. And a close up of the Q1 to Q2 cascading failures and the burnt traces on the back of the board that were visually obvious....

[Jesse Pearson]

Hey guys, I was given a blown up Ensoniq SQ2 synth to keep and fix. The SQ2 went out at a gig. I checked it out the next day and the screen still worked but...

[Jesse Pearson]

Thanks for the heads up G1, reading "the dreaded switching jack problem" now. Wow, duh...I had no idea there was a Trouble shooting, repair section...

[Jesse Pearson]

Thanks for the heads up Enzo, I'll add that to my own kit and research it's different applications to add to my knowledge base. Well, I threw out a cord...

[Jesse Pearson]

Hi G1, I was thinking the same thing and maybe the guitar cord was acting up? Thanks

[Jesse Pearson]

o. k. I just got back to the studio and ran the guitar cord test with the volume down. It's now acting like the expected standard EMI from the strat pickup,...

[Jesse Pearson]

Hi Enzo, I posted before I was able to see your last post. So it's clear we're on the same page, great. Concerning the power tube misunderstanding, that...

[Jesse Pearson]

Yes, now I'm getting hip. The Sovtek is pretty close to the JCM 800 and like the JCM 800, the high input uses both gain stages of V1 (the first preamp tube)...

[Jesse Pearson]

Well I'm looking at the schematic and for the life of me I can't see how the first power tube gets bypassed by the low gain jack when engaged? It looks...

[Jesse Pearson]

The amp has this loud hum/hiss issue when nothing is plugged into the amp or is plugged into the high gain channel, same quality and level of hum/hiss there....