Trinity TC-15 Combo BuildI took these pictures while building my first guitar amp, the Trinity TC-15 combo. I thought these pictures might help anyone doing their first amp build project. For more info check out: The first step was to solder all the components onto the eyelet board. Masking tape helps hold each part in place while soldering. I tried to mount each cap so that its value (printed on the side) was facing up. This helps a repair tech if he/she needs to work on the amp later. The wires sticking out all over are called "flying leads". They will be trimmed back later and soldered to other components mounted in the chassis (tube sockets, pots, etc.) Here's the front of the eyelet board when completed:
And here's the back of the board:
Then I mounted the tube sockets and tag strips into the chassis:
I decided to substitute #6 screws for the #4's provided with the kit, #6 fit the screw holes without any drilling and seemed a little stronger to me. Once again, I found masking tape works well for holding a screw in place while trying to start the nut. I decided to mount the transformers and can cap next:
And then I mounted everything on front of the chassis - front panel, pots, jacks and switches:
At this point I thought it would be a good idea to test the power transformer, so I wired up all the leads as shown here:
The red wire sticking up on the left side of the picture comes from the standby switch. Everything up to that point is wired now. I used a piece of test equipment called a Variac as an added precaution to bring up the power to the amp slowly:
The voltmeter is measuring the AC voltage from the transformer's high voltage secondary. I watched the current draw on the Variac meter while increasing the line voltage slowly. The current should stay well below 2 amps. I also watched for smoke, sparks, etc.!! NOTE: You do not need a Variac to test your amp, the fuse will protect the transformer when you power on. Like I said, this is added protection when starting the amp up the first time. I connected the heater wires, output transformer, impedance selector switch, rectifier and filter cap next:
I used the Variac test to power up the amp after wiring each part (i.e. heater wires, then test, output transformer, then test, etc.) to check for any shorted wires or wiring errors. During this step I found a "solder blob" had run down inside one of the tube socket pins. I tried to clean it up, but was not happy with the way the socket pin looked afterward. I emailed Stephen Cohrs at Trinity Amps about it and he sent two new sockets to me, the same day, free of charge! This is an example of the great service the folks at Trinity offer their customers. The next day a winter storm blew through Nebraska, perfect weather for building a guitar amp!
I decided "Classic Queen" would be appropriate on the MP3 player while building a TC-15, in honor of those great Brian May Vox amp tones:
Today the first thing to do was mounting the eyelet board into the chassis and soldering the flying leads to the tube sockets and tag strips:
You can get a good look here at the optional "crunch/munch switch". I installed it into a spare hole in the chassis. I was curious just what the difference in tone would be between the 8K or 5K output transformer primary windings. This switch makes it easy to compare the two with a quick flip. (BTW - I'm glad I added the switch, it gives the amp two very different tones when turning up the Master Volume and overdriving the output tubes). Setting the chassis upright (with the tube sockets on the bottom) makes it much easier to soldier the sockets:
Here's what the connections look like to the pots:
The tone contour switch is wired outside the chassis:
Here's what it looks like when completed and installed into the chassis:
I used insulation stripped from hookup wire to cover the leads of the caps mounted on the tone contour switch. The input jacks are much easier to wire outside the chassis. I mounted them into a scrap of cardboard while soldering things together:
Here the jacks are mounted inside the chassis: I put knobs on next. Gotta love the white knobs on the black panel!
I used JJ Electronic tubes with this build:
A close-up of the preamp tube wiring:
And the power amp tubes:
A good look at channel 1's wiring:
And channel 2:
The switches, indicator light and filter cap:
Here are a couple of aerial shots:
After going through the final power up procedure explained in the Amp Builders Guide, I plugged the amp into a 12" Tone Tubby alnico mounted in an old Marshall combo cab. This is me the first time I heard my TC-15:
This amp is awesome!!!! |
