Each fi ne production tube is tested and matched to our exacting specifi cations. 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 proecedure!
Take unit off standby and allow a few seconds for the circut 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 .055 to .060 volts is normal. If not in this range, adjust by turning bias screw SLOWLY a small
amount.
Do not set above .070!
For other tube types (5881, 6550, EL34) check with the manufactureer or contact us for recommendations.
Settings higher than .065 with 6L6 tubes may cause premature tube wear and possibly damage the amplifi er.
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 qualifi ed service person only.
LINE CORD- For your safety, connect to grounded A/C receptacle only.
V1- 12AX7, Rhythm channel
V2- 12AX7, Lead Channel
V3- 5751/12AT7, Reverb Driver
V4- 12AX7, Reverb/effects
V5- 12AX7. Phase Inverter
V6,V7- 6L6GC, Output
V8, V9- 6L6GC, Output (100 Watt)