Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Craft,
published 1929 - 1953. All copyrights are hereby acknowledged.
This Radio Service Data Sheet covers the
Ford-Philco radio model FT9, 6-tube auto-radio receiver. Most - if not all - electronics servicemen had subscriptions
to these magazines because they were a ready source of not just these service sheets, but because of the extensive
articles offering advice on servicing radios and televisions. In fact, many electronics manufacturers had a policy
of supplying service data only to bona fide shops. A large list is included at the bottom of the page of similar
documents from vintage receiver schematics, troubleshooting tips, and alignment procedures. They were originally
published in magazines like Radio-Craft, Radio and Television News, Radio News, etc.
I scan and post them for the benefit of hobbyists who restore and service vintage electronics equipment.
Ford-Philco Radio, Model FT9, 6-Tube Auto-Radio Receiver Radio Service Data Sheet
A fully-charged, heavy-duty battery should be used when testing
this set. For all alignments an output meter should be connected
to the plate of V5 and to chassis. The lead from the signal
generator must be connected to the cap of V3 through a 0.1-mf.
condenser. The tone control must be set at "brilliant" and the
volume control set at maximum. The attenuator on the generator
is set so that the signal is audible but not loud. Adjust C8
and then C7 for best output. Then remove the generator lead
from V3 and connect it to the cap of V2 through the 0.1-mf.
condenser. Adjust C6 and then C5 for best output. Remove the
lead from V2 and connect to the cap of V1 through the same condenser.
Adjust the signal generator to 1,600 kc. Turn the tuning condenser
plates as far out of mesh as they will go, and in this position
balance the high-frequency padder, C3, and the R.F. padder,
C2, for best response. This setting should correspond to 160
on the dial. Turn the receiver condenser to about 580 kc., 58
on the dial, and adjust the signal generator to the same position.
Rock the tuning condenser back and forth at the same time turning
the low-frequency padder, C4 for highest response. The high-frequency
position should now be readjusted. Turn the receiver condenser
plates out as far as they will go and adjust the generator to
1,600 kc. Then adjust the high-frequency padder, C3 again for
maximum reading on the output indicator.
The antenna circuit is now tuned. Connect the antenna lead
of the set to the antenna lead of the generator through a 125
mmf. condenser. Revolve the receiver tuning condenser to 1,400
kc., and set the generator dial at the same figure. Adjust C1
and C4 for highest output.
If the above procedure has been carefully followed the receiver
will now be in alignment.
When the antenna stage is adjusted with the receiver installed
in the car, the receiver antenna lead must be connected to the
car antenna in the usual manner. The signal generator lead must
be connected to a wire placed near the car antenna, but not
connected to it.
No voltage readings are given for this set, since the manufacturer
feels that they would be misleading, due to discrepancies in
battery voltage, resistance of leads, and other variable factors.
A slight change in signal voltage produces a relatively large
change in operating voltages of the set.
Posted October 22, 2015
Radio Service Data Sheets
These schematics, tuning instructions, and other data are reproduced from my
collection of vintage radio and electronics magazines. As back in the era, similar
schematic and service info was available for purchase from sources such as
SAMS Photofacts, but these printings
were a no-cost bonus for readers. There are 227 Radio Service Data Sheets as of
December 28, 2020.
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