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Tube Complement
V1- 12AX7, Clean Pre Amp
V2- 12AX7, Lead Pre Amp
V3- 12AX7, Phase Inverter
V4 and V5- 6L6 (35) or 6V6 (22) Power Tubes
Each fine production tube is tested and matched to our exacting specifications. External bias adjustment and
test points are located on the chassis near the output tube sockets. A digital voltmeter and small screwdriver are
required for bias adjustment.
BIAS ADJUSTMENTS:
Power up unit and connect proper speaker load.
Set master volumes and effects return controls to zero.
DO NOT
apply any signal to the input during the biasing procedure!
Take unit off standby and allow a few seconds for the circuit to stabilize.
Set voltmeter to Millivolt scale (or lowest volt scale 60 millivolts=.060 volts.)
With meter grounded to chassis and + probe at test point, measure voltage.
A reading of 0.055 to 0.060 volts is normal for 50 Watt amplifiers with (2) 6L6’s or 6V6’s.
If not in this range, adjust by turning bias screw SLOWLY a small amount.
Do not set above .070!
Settings higher than .065 with 6L6 tubes may cause premature tube wear and possibly damage the amplifier.
Keep in mind that tubes vary in quality, and some tubes can handle upwards of 40 ma each (a reading at the test
point of .080!) However, to be on the safe side, use the above as a guide.
WARNING!
No user serviceable parts inside! Refer to qualified service person only.
All Fuses are 3AG Type 250 Volt, SLO-BLO
Export 220, 230, 240 Fuses:
1 AMP - Jet and Jet Signature
Export 100 Volt/Domestic
2 AMP - Jet and Jet Sigmature
Fuse Chart