Evening star., 1924-10-24
How To Bald the. "BiE Brother OF
the SuPeFsensitive One-Tube Set.
;. Part Nv.

How to Butld the. ~HiH Brother OF
the SuPeFsensitive One-Tube Set.
IS Part Nv.
Now connect the p terminal Of
socket II With the A terminal of
tickler coil 6 Of the variocoupler. This
terminal Is shown on the real bear
ing Of the Yariocoupler. near. the
shaft.
The other terminal Of the tickler
coil. on the front mounting bracket
OF the instrument, Is connected with
the A terminal Of jack Z and with the
A terminal of, condenser 1S. i.
The B terminal Of jack is con-
nected with the = terminal of trans
former -. The c terminal OF jack
z is connected with the b terminal
Of transformer -,
The G terminal OF transformer 10
should then be connected with the G
terminal. Of socket 60.
Next connect the p terminal of
socket 20 with the A terminal Of
jack II. Ths. B terminal of jack II
should be connected with the p ter
minal Of transformer Pin The c ter
minal of Jack II should be connected
with the B terminal of transformer
81. =
The D terminal Of jack can then
be connected with the D terminal OF
jack IL, and this connecting wire can
be connected in turn with the posi-
tive b battery terminal "a
Now connect the q terminal OF
transformer 21 with the q terminal
OF socket 26.
Connections to Jack.
The P terminal Of socket % is then
connected with the \ terminal OF
jack Is. The B terminal of jack IS
l. to- nal n
transformer 81. The G terminal OF
jack Is Is connected with the b ter
minal Of transformer q.
Next connect the G. terminal or
transformer % with the G terminal
of socket 20, and the A terminal of
condenser 80.
The p terminal of socket 20 should
then be connected with the A term
inal OF jack 10.
Then connect together in the or
der named, the B terminal of jack
Is: the D terminal OF jack Is and the
positive r battery terminal 20.
The wiring is completed BY con-
Meeting together the negative termi-
nal Of c battery IS. the A terminal OF
transformer 81. the A terminal or
TRANSFORMER 81 and the A terminal or
transformer 1s.-
In some transformers the grid re-
turn feavf of the secondary winding
is marked F instead of A. II such Is
the case with your transformers
merely connect the F terminal where
the A terminals are mentioned apoNe.
To mount the set in cabinet you
will find II necessary 10 cut a rectan-
eular hole in the back OF the cablnet
to allow the binding post panel to go
through. unless your cabinet Is more
than seven inches deer.
The Battery Connections.
The negative A battery lead is con-
nected with terminal 2s: the positive
4 battery and negative + battery
lead IS connected with terminal "a;
terminal - is connected with the 4o-
volt terminal OF the r battery, while
terminal % is connected with the
highest voltage OF the + battery. This
voltage can be as high as lSo volts.
although 90 volts VIII give ample
The tuning of the set is simplicity
itself The best settings of the
switches can be determined By trial.
trying different combinations and
then moving the condenser and tick
Ter coil throughout their ranges.
The tickler coil should be set so
that its axis is al right angles to the
axis of the stator coil when first tuR-
ing in station. After the proper
switch settings have been made. the
only critical adjustments are those
of the condenser and Of the tickler
coil. The rheostat settings are not
critical.
When only one tube is being con-
troiled from a rheostat. the resist