repair TKO 115 Bass Amp

[Maxrocks]

I need help on how to take apart my Pevey TKO 115 amp, it was working fine approximately one month ago, my wife moved the amp and now when I turn it on no sound once connected to Bass Guitar, I used another guitar amp and all worked well.

So how do I disassemble this amp, it is either a fuse or switch, I have no clue how to take it apart without damaging the exterior. Can anyone help the amp has been used maybe 20 times in 20 years.

Thanks Bob

[Mick Bailey]

Hi and welcome to the forum.

Does the power light come on?

[g1]

Have you filed for divorce?
Before any disassembly, connect a patch cord between "pre-out" and "pwr in" and see if you get sound.

[Enzo]

Unplug it from the wall. Up top are two metal straps, near each side end . Two screws in each. Those four screws come out. In some versions there may be no strap, just black screws. In any case, not the handle, and not the corner protectors, but the other top screws come out. Now look at the rear panel, the bottom edge of the rear panel should have three, four, maybe five screws down into the wood. Those come out. That should free the chassis, which slides out the rear. I don't think on this one, but SOME amps have a screw or two in the side panel into the chassis, so look.

The chassis may snag on the top edge of the speaker grille, or be wedged there. it will come free if you work at it. Also, it is possible a corner of the chassis could snag on the edge of the tolex or something inside.

be prepared to have the wires from the speaker hold you up. usually there is enough slack in the wires you can get it halfway out. Then you disconnect the speaker wires from the circuit board. You may have to cut a plastic wire tie to free the wires. I suggest when you get to this step, turn the amp on its side or even upside down, so you don't have to fight gravity or work up under the chassis to free the wires.

[oc disorder]

After you check and report back re Mick's question G1's suggestion reflects a common problem
where the sound cannot get through the power in jack's internal switch due to a dirty connection.
That pre-out and power in loop ,allows you to put an external effects unit in the audio pathway
and when you unplug it, a small internal contact is supposed to close allowing the pre-amp to
directly connect to the power amp like it's supposed to when not being used.
Sometimes it gets a bit of grit or oxidation that breaks the signal/sound flow.
See this reference that has been made a "sticky" in this section.
(Post #22 has a working copy of the PDF.)
See here:-
http://music-electronics-forum.com/t28549/

I should point out here it also may have a headphone socket which disconnects the speaker when
headphones are plugged in.

This can suffer from a similar fate - ie the contacts won't close properly as some spider or whatever
has dirtied up the contacts.
Plugging headphones in there will tell you if the sound is there and often pushing in and removing a
jack plug there may free any trapped gunk.

All the above can be checked before removing the head from the cabinet, the details of which
Enzo has just posted.

[Maxrocks]

Hi and welcome to the forum.

Does the power light come on?

Yes the power light does come on, I do here the input jack when plugged into Guitar, I used different wires, nothing, however taking the unit apart was easy, even though I took almost every screw out before I realized how easy it was.

[Maxrocks]

Hi Enzo, thank you for the great instructions, learning curve. I have the unit apart and circuit board out, speaking disconnected, also I have 3 fuses which seem to be ok. I tried to open oc-Disoder PDF, however I get a blank page.

[oc disorder]

Post #22 on that page

Here's a direct link to the PDF Jazz P. Bass posted

http://music-electronics-forum.com/a...ck-problem.pdf

[Maxrocks]

Thank you oc disorder, I will try this and let you all know if I got my amp working. Thanks for helping

[Maxrocks]

I want to thank everyone for your help and guidance, who say' you can't teach an old new tricks...................
I cleaned all the amps in and out inlets, made sure all connections were secure, put it back together, turned on, I can hear the amp is working, connected Bass and BAM we have a amp.

Again thank you all for the advice and help. Bob