Metropoulos Forum

Hello all,

This is my first post. I'm currently building a jtm45 and I'm having a few issues.

1. I had a stray washer fall into the underside of the power transformer while I was connecting the circuit board. I've tried everything short of taking apart the thing to get the washer out. My question is, would it cause any problems to have a loose piece of metal floating around in there when I turn it on?

2. All my voltages look correct. However, I turned down all of the controls before I flipped the power switch. When I did turn it on, I heard an ungodly buzz. Almost as if the speaker can it was hooked up to was oscillating at its peak volume. Any idea what this could be caused by?

I've tried looking up the problem but all my leads turn into dead ends..

Thanks all

Personally, I wouldnt be leaving the washer floating around in there. Its a good idea to cover the gaps between the windings & laminate core with tape during construction of the amp, just to be sure of avoiding anything dropping in there. Cheers

dont use it with a washer inside the PT

The noise you heard is likely caused by your OT primary leads being on the wrong power tube socket. Simply swap the wires going to pin 3 of each power tube socket and try the amp again. This is a fairly common issue with new builds and is easy to cure. As for the washer....have you tried using a strong magnet to pull it out of the PT?

danman wrote:The noise you heard is likely caused by your OT primary leads being on the wrong power tube socket. Simply swap the wires going to pin 3 of each power tube socket and try the amp again. This is a fairly common issue with new builds and is easy to cure. As for the washer....have you tried using a strong magnet to pull it out of the PT?

Thanks for the advice, I switched the OT leads and it solved the problem! As for the washer, I'm going to continue trying to fish it out

Happy to hear that you got it up and running! I also had a washer slip into the PT on my first build. I ended up having to remove the PT to shake it out. Hope you get it!