Peavey KB-1 issue

[gtrplayr1976]

Hey folks,

I was just given a Peavey KB-1 amp. The friend that gave it to me said that when he turned it on it would just squeal with no input. Now he says it powers up ,but has no sound. I will power it up ,and see what I get myself, but thought there may be an obvious answer. Seems I've heard this issue with other amps ,but I just can't remember what the issue was. I'll include the schematics in case someone else has one .

Thanks a heap !

[soundguruman]

A bad op amp, or a broken connection on the jacks.

[Enzo]

The obvious answer is to go ahead and plug it in to see what it is doing. For all we know, the original person had no clue and was using a bad cord.

[gtrplayr1976]

Thanks folks. I did check it before ,and the noise was hit ,and miss. Found the issue as soon as I started taking it apart. The #1 input jack just fell right off the board. Resoldered the jacks, and it works fine.

[misterc57]

Can anyone point me to a KB-1 schematic? I cannot download the one in this thread.

Also could use some advice on a KB-1 issue. Channel One has a ghost wind type noise. It is present with nothing plugged into the amp. It gets louder as you increase the volume pot. Channel two works fine.

I have the board out and there are no obvious issues; no broken connections, etc. traces look good. I am going to step through the components in the schematic path once I obtain a schematic. Any suggestions would be appreciated.

Thanks!

[Enzo]

PV customer service will send you any schematic you ask for.

sounds like a noisy semiconductor, probably the op amp in that channel.

[misterc57]

op amp test?

PV customer service will send you any schematic you ask for.

sounds like a noisy semiconductor, probably the op amp in that channel.

Is there any way to test an op amp without a scope?

Thanks again!

[gtrplayr1976]

Can anyone point me to a KB-1 schematic? I cannot download the one in this thread.

Also could use some advice on a KB-1 issue. Channel One has a ghost wind type noise. It is present with nothing plugged into the amp. It gets louder as you increase the volume pot. Channel two works fine.

I have the board out and there are no obvious issues; no broken connections, etc. traces look good. I am going to step through the components in the schematic path once I obtain a schematic. Any suggestions would be appreciated.

Thanks!

If this doesn't work I can repost, or email it to you.

[Jazz P Bass]

If this doesn't work I can repost, or email it to you.

You cannot simply repost a file from the crashed archive.
The file SIZE must be changed.
I use CutePdf Writer & 'reprint as a pdf' the file, which changes the size.
Done deal.
Note: I know it's a PITA but that is the only way to get these wonderful files back up in 'the MEF Cloud'.

[gtrplayr1976]

I did not know that. Thanks Jazz !

[misterc57]

email pdf, thank you

If this doesn't work I can repost, or email it to you.

Peavey is closed for the week, so I will not be able to request a schematic from them until next week.

Thank you!

[misterc57]

schematic received

I have been emailed the schematic. Thank you!

[Jazz P Bass]

Peavey KB-1 Schematic

Here is the resized file.

[misterc57]

I am waiting on a replacement 4560 op amp to arrive. It is currently on back order.

[Enzo]

A 4580 will work fine, as would a TL072.