Evening star., 1924-06-02
How to Build a Supersensitive In
door Aerial Receiver. Part Nv.

The flament circuits of the radio
aihpiiner stages are completed by
connecting together the F2 terminals
OF sockets "a. 27 and 2s and the A
terminal of rheostat s, according to
oasrams previously published with
lnis series. The filament circuit of
the oetector stage is completed by
connecting the F2 terminal of socket
oo with the A terminal Of rheostat Q.
Inc niament circuits of the radio
ampiiner circuits are completed hy
connecting together the F2 terminals
OF sockets 80 and SO and the A t.ru;-
nal OF rheostat 10. a 'erfni-
- ne rest OF the wiring to comnIeto
ri -ne srld and plate circuits of tha
ases Is a very simple matter
with ith"nect nee Inc terminal Of socket 81
former =, Terminal of vario-traus-
socket q sfaneef slth sss the P tss terminal Of
tar;a U;-transformer ~. Connect Tho p
ninaI reir,n1nas of socket 2s with the n Ter
The g g ter tsarlo. transformer ~.
II is connected with the q terrni-
var,i oi socket 81 The G terminal nf
wit transformer 12 is connected
Ne Nert ahe III u terminal Of socket 2s.
tarrsI run wire connectinp The d
terminals OF vario-transformas. ne ~ %
ana 81 ~, the B terminal Of condan, 20, -
90 ana binding post 26. A"ehser
detect. 10 complete the wiring of the
minai OF sage: uast Connect the G ter
ia, Lne q terminal OF grid condenser and
Then connect the p ta-ni
,,.it o! the grid condenser ana Iaak
the G terminal of socket so
Other Connections.
nectad tefmin2l of socket 80 is con-
G1 The % with with the a spring of jack is.
connected GO with the B sprinp ns iacS iS
-. me terminal of transformer "a
10 Ionnected with the C. terminal ~
isch q no ~. The d terminal of Jack is
The nd g termioaf WITH tn binding post 81.
connected with the G terminaI rs rs
socket 80. The G. terminal nf tr.no ol
ttormer 10 is connected with the q
eerHninaI OF socket 49,
socket 32 with the A terminal of iack
-. Inc terminal Of transformer Is
snould be connected with the r Ter.
.nIndi OF jack 20. The b terminal of
ur:ansiorner 10 should be connected
WIN the terminal of lack 90
Next connect the p terminal of
so SOCKET 80 with the A terminal of jack
q. Ihen connect the d terminal of
JACK "a ~ with the B terminal of lack
wirinae W hna " With IN binding post s5. The
~, inS OF the receiver is completed
py joining the F. terminals OF trans-
FORMERS II and Is together and with
tne volt terminal of C battery "a
II Wv 2O1A or wv 199 tubes are used
,hroughout connect the negative r
oattery lead with binding post %:
uimuihs ,,.i.l. post 70 should be connected
with a voltage of from As to 67I1
volts; binding post 81 should be con-
nected with a voltage of from Ak IA
o. y volts. and binding post 35 should
oe oe connected with voltage of about
80 volts If a soft detector tube Of
the wv 200 is used as a detec.or
binding post 81 should be connected
volts. y
A little practice is required before
pest results are obtained. When i'm
properly operated there is tendency
to howl This bowling can be elimi-
mated by adjustment of the poten-
tiometer and the vario-transformers.
In operating the receiver the trans
former dials should not be set at their
pest point TO start with, but rather to
one side or another of the wave
length to be received. If a low wave
length station is desired. the dials
should be set SO that the transformer
= = set for a higher wave length. II
high wave length station Is to be re-
reived, the diaIs should be set to
lower wave length. The signal can
then be tuned in by means Of the
switches and s. the variable con-
denser and the potentiometer
Strengthening of Signal
The dia1s OF the tranfor7ners are
hen adjusted to strengthen the
'ignal. AS they are moved the
.trength OF the signal increases until
I point is reached when a click is
heard or the set goes into oscilIa-
ion. When this happens note the
setting at which this occurs The
lial should be turned back and the
process of readjustment gone through
gain without carrying IL to the