Limited Warranty - Audio Research VT100 Manual

Model
VT100
Output Tube Bias Adjustment
As shipped from the factory, the output bias
adjustments are set for a nominal 65mA per 6550C tube.
Under these idle conditions the tubes are each dissipating
approximately 27 watts of their 41 watt rating (35
watt plate, 6 watt screen). This point of operation provides
"enriched" Class AB 1 , and will satisfy the most critical
listener.
For best results, operate and adjust the VT100 at the
normal rated line voltage listed on the rear panel. Adjust-
ment must be made under zero-signal conditions after at
least 15 minutes of uninterrupted stabilization time.
A digital voltmeter capable of accurate measurements with
lmVDC resolution is preferred for accurate adjustment
(must have 3112 digit display). Use the plastic alignment
tool provided to make the adjustment. The test points are
accessible from the top of the circuit boards above the out-
put tubes. For the VTlOO and VTIOOMKII adjust the bias at
one place on each channel for an average reading of
!30mVDC (0. 13 Volt DC) between test points (across 0.5
ohm resistor). For the VT!OOMKIIl adjust the bias in 2
places on each channel for 65mVDC (.065VDC) between
test points (across 0.50 ohm resistor). Caution, resistor is
420V above ground.
Cleaning
To maintain the new appearance of this unit, occasionally
wipe the front panel and top cover with a soft. damp (not
wet) cloth to remove dust. A mild, non-alkaline soap solu-
tion or dilute isopropyl alcohol may be used to remove
fingerprints or similar smudges. Cleaners containing abra-
sives should not be used as they will damage the anodized
finish of the front panel. A small, soft paint brush is effec-
tive in removing dust from bevels, the recessed nameplate
and other features of the front panel.
4
Limited Warranty
Audio Research Corporation products are covered by a 3-
Year Limited Warranty (all products except CD players,
transports, and vacuum tubes). a 2-Year Limited Warranty
(CD players and transports), or a 90-Day Limited War'ranty
(vacuum tubes). This Limited Warranty initiates from the
date of purchase, and is limited to the original purchaser, or
in the case of demonstration equipment, limited to the
balance of warranty remaining after original shipment to
the retailer or importer.
In the United States, the specific terms, conditions and
remedies for fulfillment of this Limited Warranty are listed
on the warranty card accompanying the product in its
shipping carton, or may be obtained from the authorized
retailer or from the Audio Research Customer Service
Department. Outside the United States, the authorized
importing retailer or distributor has accepted the responsi-
bility for warranty of Audio Research products sold by
them The specific terms and remedies for fulfillment of
the Limited Warranty may vary from country to country.
Warranty service should normally be obtained from the
importing retailer or distributor from whom the product
was purchased.
In the unlikely event that technical service beyond the abil-
ity of the importer is required, Audio Research will fulfill
the terms and conditions of the Limited Warranty. Such
product must be returned at the purchaser's expense to the
Audio Research factory, along with a photocopy of the
dated purchase receipt for the product, a written descrip-
tion of the problern(s) encountered, and any information
necessary for return shipment. The cost of return shipment
is the responsibility of the purchaser.