New-York tribune., 1922-07-23
super.regeneratlve Trouble

Question: have constructed The Arm
strong supef-regenerative hook-up from me
Information obtained and also from your
advice. ] have adhered 70 thls hooN-us
very rigidly regarding the voltage ani
polarities as shown and also regarding the
various inducfivo elements, Win inc 81
cepti0n Of the two choke coils IN pace
OF the 100 miiiihenries iron core chohe
coli 1 have used an Acme iron choke coil.
with approx imstoly 1000 turns of wire IN
tho coil I DO not know tho rating OF this
choke. but ] have figured. according To
standard formula. about ffty milihenutH.
1 have also substituted the primary ana
also secondary windinRs ~ trantiormefs
for choke coil For the ten inillihenfles
choke coil have used various -. !"
honeycomb coils from 400 20 500 turns
The substifution of these various elements
does not seem 10 alter the results 20 that
you can notice it and az the same TIME
40 not get the proper results / can llf
barely hear WIZ on the indoor coil Ihis
indoor coil is constructed or standard
aerial wire. twelve turns spaced ohe-hali
inch. measuring three feet on tho dlagonsl
ana Ia similar In shape 10 tho one demon
strated at Havcmeyer Hall Ihe Nafl0
coupler that J. use ~ % Tuska varo-couller
with an antl-capacty switch for ioa1lhk
the secondary. ! get WIZ on the position
81 This switch for 200 meter waves. but
not AZ the other positions. ! have also
tried this hOOk-up on the offiai WIN .
little better reruit. but 90 not ger any
resuffa when the ground connection -
made .Of course / understand that ~ Is
practically imperative on an aerlai con
nection. but ! do not understand why
am unable 10 get the proper Iesul ron i,
this arrangement. and hope you can
enfchten me Are hOneycomb coils al
right for the ten millihenries chokts IN
the above hook-up / use hve-watt tune
and my B batteries are made up or elEht
storage B batteries tOtaling an even zoo
volts also notice that there is great
deal of body capacity about THIS hooh-up,
which ] suppose, II on account OF NOV
having the elements moro compact IN ar
raneement I have also found thai "a
00Os variable condenser across the Naflot
coupler secondary terminals mas htlpe"
sorreyhat on this hoOk-up with the mat'-
,tsi on hand that 1 have used. In adjust
ing the above hOok-up ] IND that me
variation of the condenser IN sefleS WIN
the 100 millihenrics choke coil ana the re-
sisfance has no effect whateFcr' regard
I as OF the setting of the condenser.-
Answer-Your trouble with the
suner-regenerative circuit seems 20 lie
| in two places First, the feed-back
coil. and second, in the iron core choke
Of the filter circuit There should be
no condenser across the feed back coil.
/ | do not think that you will get the
same results through loading as you
will by having the coil compact.
would suggest that you rewire the sec
+ ondary Of the vsrio-coupler, putting on
about twice the number OF turns that
II has al present and eliminating the
switch. The fact that the variable
condenser in series with the iron core
choke you are using does not vary the
cor ditions would indicate that the
choke coil is not suitable. ! think
that YOU can obtain one Of these CHOKE
coils through some telephone supply
house. You can use the 40O-turn duo
lateral coil for the 10 millihenries high
frequency choSe.