Fisher 60 61 65 Service Manual

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SERVICE AND
MAINTENANCE
NOTES

MODELS 60, 61, 65

COMPRISING:

60-R TUNER
60vA AMPLIFIER
60-AP POWER SUPPLY

FISHER RADIO CORPORATION
, NEW YORK, N. Y. '

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,2 GENERAL INFORMATION

iTHE FISHER Custom Sixty has been designed for those
fdesiring an FM4AM receiver of professional quality. It com!
lprises a. two'band superheterodyne circuit and employs completely
iindependent RF and IF channels for AM and FM. There are
lthree stages of IF and a ratio detector on FM, one stage of IF
ion AM and a tuned RF stage ahead of the first detector on both
2AM and FM. Automatic Frequency Control (AFC) is incorr
lporated on FM to assure accurate'tuning and complete freedom
from drift. The Fisher Custom Sixty is supplied with built'in
{FM and AM antennas. Terminals are also provided for connec'
ition of external antennas, where the latter are desirable The
Sextemal FM antenna input is designed to operate either with
ISOO'ohm balanced lead'in or 72'ohm coaxial shielded lead-in.

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§The sixtywatt audio amplifier employs push'pull parallel power
goutput to assure extremely low distortion even at high power.
EThe carefully designed flywheel tuning mechanism is unexcelled
sin simplicity and ease of station selection. «The slide rule dial
iglass has large, easyeto'rcad numerals, edge lighted There are
findividual channel indicator lights. Receptacles are available
,for instant connection of the FISHER Dynamic Range Expanr
der. An auxiliary input receptable is furnished for connection
to the sound channel of a television receiver, microphone
pro-amplifier, etc. The receiver is connected to this jack when
the Channel Selector Switch is turned to the TV" position.
An AC receptacle mounted on the roar apron of the chassis
supplies current for the Operation of a Television Receiver when
the Channel Selector Switch is turned to the "TV position.

OPERATING INSTRUCTIONS
ANTENNAS

The builtvin FM antenna is of the folded dipole type and is
satisfactory in most urban locations. Where reception is desired
either from weak or remote FM stations, we recommend the
use of the specially matched, FISHER FM Antenna System.

The AM antenna consists of a loop mounted inside the speaker
compartment. It is the only antenna required for rcception of
local broadcast stations, except where the receiver is used in
unusually noisy locations or at a distance from broadcasting cen'
ters. In the event that an outside antenna is required, we recom-
mend the use of THE FISHER Noise'Reducing Antenna
System. This system offers optimum elhciency in bringing, from
the roof to the receiver, the signal available in the location in
which the receiver is to be used. CAUTION: NEVER dis'
connect the AM loop antenna plug, whether or not the receiver
is used with an external antenna.

ON-OFF SWITCH

The OneOff Switch and the Bass :Tonc Control are regulated by
the same knob. When turning the set on continue the rotation
of the knob to that point which gives the desired degree of bass
intensity. For further details see Bass Tone Control."

TONE CONTROLS

TREBLE TONE CONTROL This control can be used to
regulate brilliance. For a more intimate tone, turn to left; for
brighter tone, turn to right. Set it at the point you find most
pleasing, for the particular program being played.

BASS TONE CONTROL. Should be set to minimum (extreme
left) on male speaking voice. For music, according to personal
taste. When playing music at low volumes, the usual loss in
bass intensity (due to ones inherently reduced hearing efficiency
at low volumes) can be compensated for by turning the control
clockwise to the desired degree.

THE FISHER DYNAMIC RANGE EXPANDER
(Optional Equipment)

THE FISHER Dynamic Range Expander is designed to restore
to records the full accents and crescendos of the original perform:
ance, usually monitored out of the recording at the time it was
made, because of the limited dimensions of the groove. Turn
the control to the right, to the desired degree. It will then operate
automatically. The main volume control should be set at that
point where, with the amount of expansion produced, the
maximum volume will be within the desired limit. NOTE: If
the Expander is purchased after the delivery of the original set,
it can be instantly connected. Simply remove the jumper that
will be found on the two receptacles marked Expander" on
the rear apron of the chassis. Connect the input of the Expander
to the receptacle on the chassis marked Expander Input"; con'
nect the output of the Expander to the receptacle on the chassis
marked "Expander Output.

CHANNEL SELECTOR SWITCH

Turn Channel Selector knob to the desired channel whether
Broadcast, FM, Phonograph, or Television Sound input. Lights
on the dial scale indicate the channel to which the knob is set.

AUTOMATIC FREQUENCY CONTROL ON FM

THE FISHER FM Receiver is equipped with an Automatic
Frequency Control, designed to simplify tuning. You will find
that when the dial pointer is brought within the vicinity of the
desired channel, the station will automatically lock in and remain
correctly tuned. It cannot drift out. The control regulating the
range of lock'in is located on the rear apron of the chassis and is
pFE'SEt at our laboratories. In some locations, however, where
a weak station is separated from a strong station by only two
channels, the latter will tend to operate the control circuit and
make it difficult to bring in the weak station. Should this occur,
turn the Automatic Frequency Control (knurled brass shaft on
the rear apron of the chassis) counter clockwise to the degree
necessary to eliminate the above condition.

ALIGNMENT PROCEDURE
AM IF ALIGNMENT

NOTE: For the following IF and RF adjustments the signal
generator should be readjuéted as necessary to maintain the
output below 2 volts across the voice coil.

1. \Vith the Selector Switch in the Broadcast position, set the
tuning capacitor for maximum capacity.

2. Feed a 455 Kc amplitude modulated signal to the signal grid
of the 68136 converter tube (pin 7 of V9) through a 0.1
mfd capacitor.

Set the Volume Control at maximum.

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Conncct an output meter across the speaker voice coil.

Adjust the top and bottom cores of the lst and 2nd IF trans:
formers (Z3 and 26) for maximum. If noise causes exces:
sive meter deflection, the Volume Control should be turned
down slightly.

BROADCAST ALIGNMENT

l. \Vith the tuning capacitor completely closed, set the pointer
to the index mark on the dial. (The first graduation mark
appearing at the extreme left of the dial scale markings.)

Connect an amplitude modulated signal generator to the
AM antenna terminals. A 200 mmfcl capacitor should be
inserted between the high" side of the generator lead and
the antenna terminaln

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