Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1922-05-26
Va 0iOrCrE1

II you have been building all Of those
SIX by six inch units that have been
recommending in these articles, you can
now put together short wave re-
generative" set md you will see what
a neat. looking bit of radio apparatus
they make. And you will also realize
how convenient this system is when
you come TO wiring up your set.
First, the dotted line represents the
wiring for the body capacity ground
You may think have been over en-
phasizing this body capacity business.
but just hook up the set and try TO
work it without a body capacity ground
and you'll change your mind.
! don't mean to say that It cant be
done But It's n nuisance. II you
haven't cared 10 go to the trouble or
"backing' all your panels with tinfoi!:
you Il have to use what friend or
mine always refers 70 as magic
wand. " This is simply stick OF thin.
but stiff. wood about eighteen inches
long on the end of which you wind
tip of insulating tape or rubber or any
thing that has considerable friction 10
il. This wand is TO turn the various
dials and SO make the adjustments
necessary to receive signals.
Not long ago ! saw in one OF the
radio magazines that the same thing
could be done with long lead pencil.
but ] never was able to make II work.
The lead in tho pencil seemed 10 make
Itself a part Of the condenser which the
human body is and | found this body
capacity" effect Just ss bad with the
pencil as without.
The wand, however. does the trick.
But it is great nuisance and 1t Is
frequently very difficult 70 make a fine
adjustment with stick the length
necessary 70 overcome this capacity.
And with this hook up you will often
find an adjustment only the width OF
q pencil line will make the difference
between good and bad reception.
As the units are arranged in the
illustration. you will notice that the
variocoupler and the two variometers
are placed as far apart as possible. This
is to keep them outside Of the influence
of each Others magnetic fields, which
I have already explained. The varIo L.
meters. built in this unit system. would
probably be far enough apart even II the
units were next TO each other. but IN
radio, as in everything else. it's better
to he safe than sorry.
There is no set way Of going about
operating this hook-up. To very
large extent. it Is simply case OF hunt
around until you find the signal you
are after. Then. on succeeding eve.
nings, you can usually find II some
where around the same adjustment
but not always.
OF course. the first thing tn do Is 10
and your desired wave length roughly
on the variocoupler. This is done by
varying the number Of turns of wire
you use in the coils Of the variocoupler
L ) 81 no ~
pling. The coupling is varied, as al.
ready explained. by rotating the bal
back and forth if you are using the
standard vnriocOupler. by raising or
lowering the top coil II you are using
our home made spider coupler and
II you are using an old fashioned loose
coupler. by pulling the inner coil out
OF the larger one or pushing II in. Per
sonally. ! have had very littIe success
with loose coupler with this hook-up
The adjustments necessary are too fine.
I have been able to hear the speech and
music fairly loudly. but have never been
really satisfactorily distinct. | much
prefer the home made spider webs &c
anv other kind of coupler. and by the
knob and thread which have described
you can get the very finest kind of ad-
justments of the coupling.
Be careful Of the brightness OF your
filament in using this hook mp. II you,
phones are noisy, try less current. II
that doesn't stop the noise. use the sa me
amount of current and see il altering
the setting Of one or the other of tb'
variocouplers wont stop it.
When you hear the first faint sound
of the broadcast. get it as clear "a you
can with the coupling and condenser III
you are using oneI and then try slowly
and carefully altering the setting of the
two variocoupers. Try the rheostat
again, too. every now and then. Anc
If you have mounted and tapped the
forty -five.volt "R" battery as | have
advised, try little more or 7sts cur.
rent from that.
That, unfortunately, is al I can tel
you about operating this set. II is a
matter Of sticking az 1t until you mas
ter it.
Copyright. Isge. BY Public Ledger con'pari