New-York tribune., 1922-09-17

Sffcuit inc rotor is we'll brnced and
positive IN it's movement.
Ihis set may be used Satisfactorily
with an outdoor aerial and for reason.
able reception distances viii rive q
strong signal when using head phoncs
hanuiacturcd by Mortimer Radio Cor.
poration.
RaHo-Frequcncy transformer
This transformer is neat and comnnci
IN appearance, the w,ndings beiny com
pleteiy encased in II black compositior
cylindrical shell two inchos high ana
one and three quarter inches in diam.
cter. The four black knurled bindino
Iosts arc mounted toccthcr on its TOP
'wo extensions with screw holes arc
provided at either side OF thc base for
attachment to the panel.
lhc windngs Of this transformer arc
'aid in slots around short length Of
insulated tubing. An air core provides
q path for the inductivc flux. and fine
iron filings form shield for the wind
ings, thus making the transformer
comparatively stable in its operation
Leads from The windings are embedded
in special insulativo wax to prevent
short-circuit. Made by the Radio Serv.
&c Laboratories.
Audio Frequency Transformer
Thin steel Nominations shaped in I
rectangular loop folm the closed mag
nctic circuit o this transformer. Tbs
I9minatlons arc gripped between cast
aluminium standards, which also scrrc
as mounting supports. The primary
and secondary windings arc insulated
with lmpregnated paper and wound in
the form of cylinder about the lower
part Of the magnetic circuit Leads
from the primary and secondary coil
terminate at binding posts mounted
upon rectangular strip Of bakeiite
along one side of the tran sformer.
ASIDE from the fact that this tran,.
iori"er is somewhat more difficult. ia
mount. due to inadequate extension Of
the legs, it will be found perfectly
satisfactory as an ampliiication unit
~ any auolo frequency circuit Over
ail the transformer stands inches
nleh and VIII require a space 21% bv
Hches Tor mounting Made by th,,
Acme Apparatus ompanv.
Head Telephone Receivers
these phones are 1900 ohms impe-
IN construction for their type and very
sensitive. The diaphrann is slipbtly
more than = inches in diameter and
inc Two small magnets that actuatc il
are wound with fine enameled wire. The
whole unit. including Che magnet and
diaphragm mounting. may be readily
separated from the aluminium casino
for inspection of tho terminals. tho nc,
tiNc parts being held in place By the
rubber ear pieces
The head spring is of round steel
tempered wire covered with brown wo-
ven cotton tubing. The phones NAV be
readlly adjusted to fit over the cars,
Made by the DictoGraph Products Cor
poratioQ
Cnmountcd Condenser
"A a. plate condonsey. with half
DISK plates on the rotor s2ih inches in
diameter, spaced nine and half to
the inch. with brass washers. Three
brass bolts support the stator plates.
triangular supports OF 3-16 inch
hiack composition at either end sup
rort the stator bolts and rotor shaft.
Stops arc provided to prevent the con-
denser going beyond the minimum and
maximum positions. Good positive
contact is made by brass spring
pressing against the rotor shaft end.
Made by the ANA lgamated Radio Sup
ply Company.
Enclosed Detector Stand
glass inclosed crystal cup mounted
horizontally upon polished black com
position base 2x3x4 inch, with
knurled rubber binding posts ct one
end for connections. A glass tube one
inch in diameter surrounds the crystal
and is easily removable.
The whisker mounted OH the end of
sliding arm. through a ball swivel
may be readily, adjusted to any point
OF the surface of the crystal. All con
ncctions are soldered. Made by the
-aDlalgamated Radio Supply Company