The Washington herald., 1922-04-22
Questions and Answers
First Installation.

set to listen in on the many radio
phone messages. AS we have never
had experience with a radio set we
do not know what to purchase. Wish
you would name a book on radio
and name some Washington dealers
where may purchase, a radio set
]. w. M.
A. can suggest no set or ap-
paratus in particular. but would ad-
wise that you visit local dealers.
look over the various sets and
watch them in operation. After a
half day spent in tina, manner you
will know more about radio re-
ceiving sets than You could learn in
many hours of reading. Ask the
dealers for their trade literature
and read it when you have time.
Pick up as much information as
possible. An elementary book on
radio is THE Wireless Expert
acser' Racher. ) and S"%TS aThe A BE Of Radio"
by waldemar Kaempffert, both for
sale by local dealers. Follow The
Herald radio page.
Two Aerial Problems.
Q. Another boy and ! live in the
cru HOuStS VI iCSpCNNiNtis
We each have receiving sets. He
has no aerial as yet, but my aerial,
100 feet long, is extended between
the houses. Can he swing his aerial
directly over mine without messing
up both sets? think he will use
vacuum tube, I use a srystal de-
tector.-C. D.
A. The. Herald some time ago re-
quested full names and addresses
on inquiries. AS often stated, re-
ceiving aerials should be al far sep
arated as possible. and IL near each
other then. at right angles. 9th
erwise when either of you are tun-
ing to a particular station, the other
may as well stand by. or else be
aggravated as each tries to get the
station.
The Bureau of Standards. which
probably conducts more experiments
than aRy other single laboratory.
finds that two antennae, spaced ten
feet. resulted in extremely poor re-
suits, the radiation between the re-
ceiving antennae being greater and
more noticeable than that from the
transmitting station. When antenna
wires are near to each other II may
be we'll to have the leads as far
separated as possible. Persons
troubled with too little space Tor
antenna room would best use the
same receiving set. il possible one
antenna, longer and more eficient
would then be possible.
Your friend having a tube set
may be equipped with radio fire.
| quency amplifiers, in which case ne
could use an indoor loop aerial,
thus eliminating some of the trou-
BILE.
Low Wave Lengths.
Please answer the following
! questions:
a. Are the Arlington type loose
couplers capable of tuning down
to the low wave lengths (that is,
| $50 meters)? Capacity of trans
former. 1000 meters.
| b. May honeycomb coils be placed
in series with the primary of
loose coupler to increase capacity?
C. Is there any advantage or dis
| advantage in use of an aerial with
| lead-in from center over one with
lead in from end?
a. For the wave length you men
tion, no tuner l am familiar with
is very efficient. A variable con-
dehser series with aerial circuit
might give you the necessary wave
length adjustment. AS explained
with Fig. in The Herald of April
13. there is circuit which will
permit tuning to extremely long or
| extremely short wave length.
b. You may vary wave length by
such a series connection. but the
effect of inserting honeycomb coils
would be to increase inductance
not capacity.
| c. The T type aerial. which takes
lead-in from the center (exact cen
teri has a lower fundamental wave
length, due to the fact that the
total inductance is less. Except for
this there is little difference be-
tween the two types. Aerials are
| designed to afford the maximum
efficiency for the wave lengths
which will be most generally re-
ceived. The Marconi Company, for
example, uses the standard com
mercial wave length of 500 meters
also $50 or 400 meters are used
This company, for a fiat top aerial
in excess of 125 feet in length, will
attach the lead-in at the center
while below that length it will be
attached to the end. This works
best for three standard lengths and
gives good values of antennae cur.
rent.
Crystal Detector Set.
Q. Will you please publish th
best hook-up for a crystal detecto
set?
| (b) I should like to know a rea
sonable dealer in electrical goods
&c. r.
A. Crystal detector hook-ups ant
thei: relative advantages were de
scribed in The Herald of March 2
and 81. April ana 13. Addres
Circulation Manager. Herald.
Insufficient Data.
Q. have an aerial 40 feet high
$50 feet long. get local concerts
but no distant stations. What =
| the cause of this?
OBJ I have it grounded to watel
pipe in the cellar.
(c) often during concerts I an
bothered by telegraph code. Wha'
is the cause of this? l inclose dia
gram of my aerial.-C. L. w.
A. without more data your ques'
/ tE.f