Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1922-04-29

ANY man who uses crystal receiver
without test buxzer Is like the dog
who sat OH a tack and just sat there
and howlcd because he wns too lazy to
Z ~ up. without buzzer to assure
YOU that your catwhisker is on a sensi-
tiye spot on the crystal, you might turn
YOUR knobs all night and not get the
faintest breath Of a signal. And you
would blame the set and say that radio
q q fake anyway and the man who
sold you the apparatus was a swindler.
II is, Of course, possible to work
crystal set without buxzer. II IL
possible to do almost anything in radio.
The great thing about the buszer is that
your detector is oil right. Then. II
you don't gct signals, you are justified
In looking to the set for the trouble.
Neat little buzzers are made especially
for this purpose, but 1t isn't necessary
10 buy one. An ordinary buzzer such
as the boss uses to call the Office boy
or such as are put on some front doors
instead of bells will do exccllent'y. And.
II you have an old electric bell. just
take off the bell, break off the clapper
arm and you are all fixed.
On all such buzzers, there are two
binding posts with screw tops for til.
wires from the battery. You wire one
Of these posts to your switch or push
button and the other to one pole of an
ordinary dry cell--not the kind used
for pocket flash lamps, but one Of the
old.fashioned cylindrical ones. Run
another wire from the other post Of the
dry cell to the other screw Of the switch
or button. .......
You will notice that the little vibrat.
ing arm that does the buzzing vibrates
between two coils and metal upright.
Tastcn n wire to this little upright
preferably by solder, but a good tight
twist will do, and run the other end Of
the wire to any part of your ground
wire. It is usually best to fasten II
directly to the ground binding post on
your receiving set.
The process Is this:
Put on the phones and press the but;
ton to make the buzzer buzz. You will
probably not hear it in your phones at
first. The sound will come obviously
from the buzzer. Keep the buzzer buzz
ing and feel around on the face Of the
crystal with the catwhisker wire and
soon you will strike sensitive spot.
This will be indicated by the sound Of
the buzzer coming unmistakably in the
phones.
Even when you are receiving signals,
you should press the button once in u
while to make sure that your contact Il
still good.
With a good spot found on the crys.
tai, you are ready to "tune in" First
move the switch blade or else the slider
Of the part Of your coupler marked
''primary" and set it to include about
twenty turns of wire.
Then. with the primary left that way,
change your ''coupling" (pu'ling inner
coil in and out with loose coupler; re-
yolving inside coil with variocoupler or
opening apart and closing with fiat
coils) at the same time, with the other
hand. turning the knob of the variable
condenser around first one way and then
the other.
If you don't get n signal, alter the
primary switch or slider to include
about six or eight more turns Of wire
and repeat the process with the other
apparatus. Keep on this way, giving
yourself all possible combinations, and
you will soon hear signal.
When you do. vary your primary by
single turns until the signal is Ioudest.
Then move the coupling a trihe and also
the variable condenser to see If you
can i'm rove it. If not, you've got 1t
at Its best.
Copyright. 1898. 1y Public Ledger Company