Little tech questions from your day

[numberthirty]

Has anyone ever had any luck replacing those cheesy switches on the top of an EXH Polychorus?

[Tommy]

Has anyone ever had any luck replacing those cheesy switches on the top of an EXH Polychorus?

Do you mean the black slide switch? If so, you probably don't need to replace it unless you've broken it off. Get yourself some DeoxIt D5 and open the pedal up. Put the straw inside the side of it and do a couple of quick sprays. Flip switch back and forth a couple of times.

If your switch is wobbly (or falling out) you can fix that too. It just means the casing isn't crimped tightly anymore. Needle nose pliers can fix that.

[Adam P]

I've been thinking about adding a master volume to my Traynor YBA-3A. Looking at the schematics here, from Scott's site, it appears that the master volume on the later models is just a 100k linear pot acting as a voltage divider right before the phase inverter. Can anyone confirm this? And what's the extraneous stuff around the pot on the schematic? I'm guessing it's just to illustrate the change made between revisions corresponding with the title block? Just want to make sure I'm not overlooking anything.

[greg]

I've been thinking about adding a master volume to my Traynor YBA-3A. Looking at the schematics here, from Scott's site, it appears that the master volume on the later models is just a 100k linear pot acting as a voltage divider right before the phase inverter. Can anyone confirm this? And what's the extraneous stuff around the pot on the schematic? I'm guessing it's just to illustrate the change made between revisions corresponding with the title block? Just want to make sure I'm not overlooking anything.

Looks that way.
The grounded, dashed lines means there's shielded wire going to and from the pot.

[Adam P]

Great, thanks.

I'm assuming the shielding would just be soldered to the back of the pot (assuming its grounded) or the lug that is tied to ground?

[greg]

You could tie it to the same ground point as the bottom leg of the pot (like the schematic shows). I wouldn't use the chassis or case of the pot as your ground. Use whatever circuit ground buss tied to the power supply or star-ground.

[japmn]

I was testing shit in my non-working Peavey Bass 400 head and found a transistor that isn't passing any continuity between any of the pins. It is marked "60142 7420" and I cannot find one on the inter net at all. Anyone have any ideas. I'll most likely have several more questions about this thing the more I dive into it.

[numberthirty]

I was testing shit in my non-working Peavey Bass 400 head and found a transistor that isn't passing any continuity between any of the pins. It is marked "60142 7420" and I cannot find one on the inter net at all. Anyone have any ideas. I'll most likely have several more questions about this thing the more I dive into it.

http://forums.peavey.com/viewtopic.php?f=20&t=7697

[japmn]

I was testing shit in my non-working Peavey Bass 400 head and found a transistor that isn't passing any continuity between any of the pins. It is marked "60142 7420" and I cannot find one on the inter net at all. Anyone have any ideas. I'll most likely have several more questions about this thing the more I dive into it.

http://forums.peavey.com/viewtopic.php?f=20&t=7697

Thanks, I also found this and it is good.

http://www.scribd.com/doc/29319120/Peavey-Semiconductor-Cross-Reference-List

[numberthirty]

I was testing shit in my non-working Peavey Bass 400 head and found a transistor that isn't passing any continuity between any of the pins. It is marked "60142 7420" and I cannot find one on the inter net at all. Anyone have any ideas. I'll most likely have several more questions about this thing the more I dive into it.

http://forums.peavey.com/viewtopic.php?f=20&t=7697

Thanks, I also found this and it is good.

http://www.scribd.com/doc/29319120/Peavey-Semiconductor-Cross-Reference-List

Jeez. You've got to be Indiana Jones to fix a Peavey.

[japmn]

I was testing shit in my non-working Peavey Bass 400 head and found a transistor that isn't passing any continuity between any of the pins. It is marked "60142 7420" and I cannot find one on the inter net at all. Anyone have any ideas. I'll most likely have several more questions about this thing the more I dive into it.

http://forums.peavey.com/viewtopic.php?f=20&t=7697

Thanks, I also found this and it is good.

http://www.scribd.com/doc/29319120/Peavey-Semiconductor-Cross-Reference-List

Jeez. You've got to be Indiana Jones to fix a Peavey.

I know. Good thing is, if the transformer is good, I could replace pretty much everything inside it for around $75.

[PEPPER!]

hey, does anybody have one of these?

if so, what's the voltage for the AC adapter? it's not listed on the unit and the Internet doesn't seem to know . . .

[numberthirty]

hey, does anybody have one of these?

if so, what's the voltage for the AC adapter? it's not listed on the unit and the Internet doesn't seem to know . . .

Are we talking you have one? Are you thinking about buying one?

[PEPPER!]

yep, going through the basement & I have one. no idea which adapter goes with it though. guess I can start trying 'em out till one works

[numberthirty]

yep, going through the basement & I have one. no idea which adapter goes with it though. guess I can start trying 'em out till one works

It seems like phantom is usually 18-48 volt. Is there anything marked 18 volt?

[Tommy]

I'd just email their support:
http://sterlingaudio.custhelp.com/app/ask

or call them: (888) 621-2154

[Teacher's Pet]

Here's a little tech question from my day:

What's the deal with talk show mics?

Are those mics on the desk actually on?
Seems like they always have boom mics going, and sometimes clip-on mics.

I'm curious if the desk mics are just for show and nostalgia. I seem to remember Dave whacking his deck mic with a pencil, but maybe I'm wrong.

What kind of mic does Conan use? Is that an AKG 414?

Yes, I am watching TV, but I am thinking about microphones.

[Paid In Full]

Here's a little tech question from my day:

What's the deal with talk show mics?

Are those mics on the desk actually on?
Seems like they always have boom mics going, and sometimes clip-on mics.

I'm curious if the desk mics are just for show and nostalgia. I seem to remember Dave whacking his deck mic with a pencil, but maybe I'm wrong.

What kind of mic does Conan use? Is that an AKG 414?

Yes, I am watching TV, but I am thinking about microphones.

The mics are props, and a standard decades-old feature of the talk show format, along with a desk for the host to sit behind and a couch for the guest. A throwback to the old radio show days.

[rgauss]

I hope this is an alright place to post this.

Does anyone have the schematic for a Moog MKPE Parametric EQ?

Word on the net is that the schematic was usually placed inside the EQ. Mine doesn't have one. Only a block diagram.

[bassdriver]

I hope this is an alright place to post this.

Does anyone have the schematic for a Moog MKPE Parametric EQ?

Word on the net is that the schematic was usually placed inside the EQ. Mine doesn't have one. Only a block diagram.

not sure if that's the model you have:

http://www.effectsdatabase.com/model/moog/pareq