Evening star., 1925-07-21
FIFTEEN MINUTES OF
RADIO EACH DAY
Charting the Trouble Spots. Part T
BY JOSEPH CALCATERRA.
All Rights Reserved Repro. Prohibited

Charting the Trouble Spots. Part I.
The greatest task in curing ailments
is locating the source OF the trouble.
The remedies for various kinds Of sick
ness, whether they are those which
affect the human body or the many
machines which serve US, are fairly
we'll known, but II is often difficult to
locate the source OF the trouble.
In this series / am going TO outline
the places where trouble is likely TO
occur. The matter in which the
trouble spots should be eliminated
will be practically self-evident, and
YOU will have no trouble in eliminat.
ing them once you know where
trouble Is likely TO be found
One OF the best ways TO keep an
automobile running in good condition
Is TO go over it occasionally before
the bolts have a chance to get loose
and drop off or before the electrical
contacts have chance to loosen up
and cause poor operation. II you will
follow out the same system with YOUR
radio set, going over the parts occa-
sionally as a mechanic tunes up
his car, you will. get more enjoyment
out OF your set by eliminating trouble
before 1t makes its appearance.
Examine Aerial System First.
The first thing to look after is YOUR
aerial system. See that the poles are
fastened rigidly; that no joints are
loose; that the insulators are in good
condition: that the lead-in over the
edge Of the roof is free and clear: that
the wire does not touch the side of
the building; that the lead-in enters
the window through a lead-in insu-
lator; that there is no undue strain on
the aerial wire which would tend to
under electric power lines: that the
leadin wire inside of the building does
not touch the walls unless II is insu-
lated therefrom by a good insulating
material: that the aerial wire is at
tached firmly to the proper aerial
binding post
Then look to your ground wire.
See that 1t makes good contact with
the ground connection and that the
point where il makes contact is clean
and not covered with rust or CRIME:
see that the other end of the wire
makes good. firm contact with the
proper ground binding post and that
the wire has not been broken.
Inspect the lightning arrester to
make sure that il is not short-circuit-
ing the aerial installation by making
direct contact between the aerial
and ground.
coils very carefully to see that there
are no poor electrical connections. 1t
is a good plan to go over every sol
dered joint with a hot soldering iron
occasionally just to make sure that
the joint is properly made.
Check Up on Short Circuits.
Make sure that the insulation has
not been removed from any of the
turns. thus causing a short-circuiting
between turns. If the unit is sealed
up, disconnect IL from the circuit and
test out the windings with a battery
and voltmeter to make sure that the
windings are intact. A set will often
work even when there is an open con-
nection in one of the coils, but it will
not operate as efficiently.
If q rotor winding is used, check up
to see that the connections made
through the shaft are really making
connection. Where pigtail or flexible
wires are used to make the connec-
ton from the rotor winding to an out
side binding post, the constant turn
ing often causes the insulation or
wires to break. See 10 1t that this
has not happened in your case. Where
the contact is made by means of fric-
ton washers, the constant turning
often weakens the spring. Take out
the bearing If necessary. and strength
en- the spring and tighten the stop
collar