The Washington herald., 1922-08-27
PRACTICAL DATA
| GIVEN CONCERNING
WORKING OF SET
WSB, Atlanta, Is Heard
In Addition to All Lo-
cal Stations.

CdI SIdtlOIlS.
The amateur at present does not
desire to invade the theoretical
and mathematical side of super
regeneration. Rather than know
th4e each oscillation In q certain
circuit makes thirty complete
trips. the amateur at present de-
ires some practical working data.
Al He must know a few underlying
principles and hold them in mind
II he expects results. For instance.
he must know which tube acts as
the oscillator; which tube acts as
delector. regenerator and amplifier.
In putting any .super-regenera-
tive set In operation, first light the
ilament of the oscillating tube
and place the phones In the circuit
10 see IL II Is functioning properly.
Secure the desired frequency of
oscillation and remove the phones
tif they are not in the oscillating
tube circuit) and close the circuit
The tube will continue to oscillate
Next light the tube acting as a
detector- and test II for detection
(if the oscillating tube acts as
detector also test IL for detection).
AuDc Is H6xi
tested and lastly the amplifier
One tube may have several func-
tions and 1t Is possible to make
one tube do all four. but this re-
ouires untold adjustments
Acts As Ampliner.
The nrst tube acts as the regen-
erative amplifer and the second
tuoe as the oscillator and the de-
te1for. Western Electric E tubes
|C& 11s) were used in the above
circuit Moorehead tubes (AP)
also were used and gave good re-
ilts. In fact any hard tube or
nve-watt power tube may be used.
but the above two were the only
ones tested in the given circuit.
The grid batteries need not be
Included in the circuit. but add
greatly to It IL properly adjusted.
Inductive relation Is maintained
between LIS and LIS in this circuit.
Having lighted the flament of
the oscillator tube. adjust the
coupling between LIS and LIS and
the condenser c. until a note OF
very high pitch is heard in the
phones. The condenser c. which
In connection with the radio fire.
1uency choke La couples the grid
and plate of the oscillator tube
will have to be placed in aproxI-
mately the maximum setting. Now
light the regenerative circuit (con-
denser c and the variocoupler and
variometer) until a signal is re-
ceived. II no signals are received
Test the oscillator tube which acts
As detector.
Lower End Used
Only the lower end of the con.
denser c. which is .O005 (21 PLATED
was used in the above circuit and
one Of lower capacity (O0025, IL
pHte) answers the purpose Just as
we'll. The condenser and stator
winding OF the vario-coupler are
to the desired wave length
IN the same manner as usual.
The coupling between the rotor
and stator OF the vario-coupler and
variometer are next adjusted
Honeycomb coils were tried here
but with not nearly as good re.
suits The signals will increase
in strength as the coupling is tight
ened until an extremely loud squeal
Is heard: advance the coupling still
further and at the same time ad.
just the filament of the oscillatol
tube. II the signals are lost, the
nlament will have to be lighted q
little brighter and the coupling
again frightened and the filament
again adjusted Qowered).
Repeat Operations.
1t may be necessary to repeat the
above operation five or six time:
before true super-regeneration il
obtained. A veriner rheostat, al.
though not necessary, will helr
things greatly.
II phone signals are being re.
ceived. approach the minimum set
ting of C2 until the high pitched
note is no longer clearly audible
A, very weak high-pitched note is
s&vays audible. The circuit is now
oscillating at a radio or superaudi-
BILE frequency.
The signals are not nearly SC
trong. but have their natural tone
and are very clear.
If a lower frequency Is desired
the coils may be wound with addi-
tional wire and the values Of ths
condensers used. The lowering ol
the frequency of the oscillator tube
gives greater application. but al
the same time produces a continu-
Gus note in the phones which makes
II dif1cult to read signals and
renders the circuit useless for
phone receptions. The signals dc
not have their natural tone.
The given circuit is designed to
oscillate at 10000 cycles just be-
tween radio and audio frequency
thus throwing negative and posi-
tive resistance into the circuit TO-
600 times a second. When the mega
tive charge Is Impressed the set
Will function. When the positive
is impressed II will not
To secure the greatest amplifica-
tion is very difficult. The set acts
similar to a three-step radio fire.
quency amplifier, detector and one
step audio Frequency amplifier al
all times. and with careful adjust
ment will equal a two-step audio
Frequency amplifier.
Three weeks were required to
Ig9 the set into successful opera
tion- All local stations and on one
ocean in wSB. Atlanta. Georgia.
rs received