Page 36 - Triwatt Custom Lead Amp Builder's Guide

If all is well, solder in your transformer’s low voltage secondary leads (120 or 230 volt primary).
Don't solder in the High Voltage (HV) secondary. Also solder in your Output Transformer (OT)
secondary.

Install your pilot lamp and the slo-blo mains fuse. Switch to standby for 1 second just to see the
pilot come on nice and bright. This checks that the 6.3VAC supply line is not shorted and is
properly connected to the lamp. If the lamp did not come on, check to see if the fuse blew. If not,
try another lamp and do the 1-second power thing again. If the fuse blows, there is a short on the
PT or mains. If the fuse survives, then it's likely that the 6.3VAC is not properly connected to the
pilot lamp. Use your AC voltmeter to check for 6.3VAC (actually more like 7VAC with no tubes
installed) at the lamp and all the tube sockets.

In the following steps, B+ is going to go to full voltage. Be extremely careful.

Assuming you now have a bright pilot light, connect your AC voltmeter to the power
transformer’s High Voltage secondary (which is still not soldered into the circuit). Turn the power
on just long enough to get a reading to verify it is correct. You should get a value 10 to 20% higher
than the rated output voltage of 700 VAC. Measure the AC voltages to ensure they are within spec
of the provided transformer schematics and specs.
If you get a value less than the rating, shut down the amp and check the fuse. If you get a proper
value from the HV secondary, power down and solder the secondary to the recto tube or diodes.
Hook your Volt Ohm Meter (VOM) to the HV secondary again.

BE VERY CAREFUL at this point. Your B+ will charge up for this power up.

Connect up the Power Supply Filter Capacitors. If not already done, install the two 50+50uF
can caps onto the chassis. These are held in place by a large clamp bolted to the chassis. Take
special note of the polarities of the can caps. Identify the two positive terminals and orient the
cap connectors as per the layout diagram. Attach the 1K5W filter and 220K 2W bleeder resistors
to them. Connections to the ground terminals and chassis ground are now made. Also, install the
jumper across the first filter cap between the two positive terminals. Wiring to the board will wait
until the board is installed.

5 Turret Board Construction
If you do not have a pre-built Trinity amps turret board, now is the time to build it.

Install the 6 jumper wires on the underside of the board. Follow the pictures below.

TrinityAmps TRIWATT Builders Guide Ver. 2.31.docx- 36 -