Metro JTM45 Build
Posted: Tue Feb 21, 2006 12:05 am
I just got started on my Metro JTM45 kit last week and thought I'd document the process. I really enjoy watching other people's amps come together, so I just thought maybe someone might find this interesting. If you're sick to death of "how I built my kit" threads, my apologies in advance.
I ordered my kit a couple weeks ago and - due to a shipping snafu - I'm still waiting on the output transformer. But I got started last weekend and I'm going slowly, as I always do. I asked George to upgrade the pots to PEC's and I took advantage of Sozo's discount offer to forum members in order to upgrade the caps. Otherwise, it's just the straight Metro kit.
Day one: hardware. I spent some time this morning installing the PT, the choke, and the tube sockets. I had a day full of personal obligations and things to do, so very little time to work on the amp.
Day two: I quickly realized that I wasn't going be happy working on the amp unless I had some sort of jig or cradle to hold the work solidly in place, so day two began with a little jig building project.
Once everything was secure I was able to go to work wiring up the PT.
and the heaters...
Day four: Since I'm waiting on the output transformer to arrive, I skipped ahead to work on the board. Here's a shot of the under board wiring:
George recommends populating the board after it's installed, but I prefer to do it before the board goes in the chassis. So, in the afternoon I started building the board... always my favorite part of the project.
Note the use of heat sinks to protect the (expensive) caps while soldering
Tomorrow will be another busy day for me so not much time for amp building. Hopefully I'll find time to work on the board in the evening. After that, I'm waiting on the arrival of the OT... hopefully by mid-week.
I ordered my kit a couple weeks ago and - due to a shipping snafu - I'm still waiting on the output transformer. But I got started last weekend and I'm going slowly, as I always do. I asked George to upgrade the pots to PEC's and I took advantage of Sozo's discount offer to forum members in order to upgrade the caps. Otherwise, it's just the straight Metro kit.
Day one: hardware. I spent some time this morning installing the PT, the choke, and the tube sockets. I had a day full of personal obligations and things to do, so very little time to work on the amp.
Day two: I quickly realized that I wasn't going be happy working on the amp unless I had some sort of jig or cradle to hold the work solidly in place, so day two began with a little jig building project.
Once everything was secure I was able to go to work wiring up the PT.
and the heaters...
Day four: Since I'm waiting on the output transformer to arrive, I skipped ahead to work on the board. Here's a shot of the under board wiring:
George recommends populating the board after it's installed, but I prefer to do it before the board goes in the chassis. So, in the afternoon I started building the board... always my favorite part of the project.
Note the use of heat sinks to protect the (expensive) caps while soldering
Tomorrow will be another busy day for me so not much time for amp building. Hopefully I'll find time to work on the board in the evening. After that, I'm waiting on the arrival of the OT... hopefully by mid-week.
I tried using George's wire but it was too "springy" so I substituted solid core wire (as you so astutely observed BashCoder)... 18 ga between the power tubes, 22 ga for the rest. A couple years ago someone showed me the trick of twisting wire by chucking it into a hand drill. The first amp I built that way came out dead quiet, so it's been my practice ever since.
