Wiring
Wiring
Use a 2 x 25 to 30Vac / 100 - 120VA transformer.
Connect the transformer to the AC power connections of the PCB.
The Velleman transformer colour scheme is specified on the pcb.
Careful : Other brands may feature a different scheme !
Do not change the BIAS-adjust trimmer!
Make sure to put a 1A T (slow-blow) fuse in series with the primary winding of the transformer (see diagram).
ADVICE: For safe first-time testing insert a 60W light bulb in series with the AC power and the transformer. If the light
bulb lights up continuously, disconnect the transformer and check all your wiring and assembly. Reconnect the power
supply. If the lamp remains off, everything is OK, replace the light bulb with a fuse.
If the TR8040 transformer is used there is a selection of primary AC voltage :
120Vac: black / brown.
230Vac: black/orange.
IMPORTANT: Insulate the wire that is not being used.
NOTE: Two amplifiers and two transformers are required for stereo. Never attempt to run two amplifiers from a single
transformer!
4
Y: yellow, R: red, B: blue, G: grey.
SOLDER
Y
R
G
B