life of the larger cells in the Home Battery
Box.
The longer life batteries should
invariably be used for continuous service.
There are several indications by which the user may determine that
the filament or "A" batteries are becoming exhausted. These are low
filament brilliancy, weak signals, and distortion, the signals becoming less
and less recognizable. When it is found necessary to turn the "Battery" setting
knob up to "10", and the operation of the set is still unsatisfactory, it is an
indication that the filament batteries are exhausted.
Plate or "B" Battery.
When signals become weak with the filaments
burning properly and other conditions normal, or if operation becomes noisy, the
"B" battery should he replaced. If a high resistance type of voltmeter is
available, the batteries may be tested. They should be discarded when the
voltage has fallen to 17 volts per 22 ½-volt block, or 34 volts per 45-volt block.
Grid or
"C"
Battery.
It is difficult to tell when this battery is exhausted
except by measurement of its voltage with a voltmeter. The safe plan is to renew
it whenever the "B" battery is replaced. Indications of an exhausted "C" battery
are distorted signals and a tendency to howl.
If
the difficulty appears to be elsewhere, it is recommended that the
services of the dealer from whom the set was purchased, be enlisted.
If the set becomes inoperative, try interchanging the Radiotrons. The
second tube from the left (when facing the front of the set) is the important one.
Try interchanging this Radiotron with either the third, fourth, or fifth Radiotrons
from the left. Use for the second Radiotron from the left (when facing the front
of the set), the one which gives the maximum response in the loud speaker or
head telephone receivers when listening to a distant station. "Station Selector 2"
should be slightly readjusted whenever the first or second Radiotrons are
changed.
If
no improvement is noted an examination of the batteries and their
connections should be made. It is of advantage to keep a spare Radiotron
UV-199 on hand to meet emergencies.
Polishing the Exterior.
If finger marks result from handling the cabinet, a
little rubbing or polishing with furniture polish will restore the finish. The polish
chosen should be of a grade which will leave the cabinet free from an
oily appearance. Use a soft piece of cotton cloth or cheesecloth free from
lint. Moisten the rag with a small quantity of the polish and rub it on the
[15]
