close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2114332

код для вставки
April 19, 1938.
R. BRUCKNER ET AL
2,114,332
KEYING
Original Filed Jan. 8, 1934
171:9" i
4139’ 5
By
VTORS
3/04/71?” BBUC/f/VEH
I900 VLF 60572. EH’
'
ATTORNEY
,
Patented Apr. 19, 1938
2,114,332
UNITED STATES
PATENT
FFl€E
2,114,332
KEYING
Richard Bruckner and Rudolf Giirtler, Berlin,
Germany, assigncrs to Telefunken Gesellschaft
fiir Drahtlose Telegraphic m. b. H., Berlin,
Germany, a corporation of Germany
Application January 8, 1934, Serial No. 705,681.
Renewed October 21, 1936. In Germany Jan
uary 9, 1933
8 Claims.
(Cl. 250-17)
This invention relates to a method of and a
circuit arrangement for the simultaneous keying
of a self-excited and a separately-excited stage
of a valve transmitter.
Telegraphic transmitters which by keying
shocks‘resulting from hard thumping of the key
may cause serious disturbances especially in re
ceivers located at close distances, should be keyed
gently and smoothly. Now, if such a transmitter
10 including one or more stages is keyed gently in a
separately-excited stage, but not in the oscilla
tion generator of the transmitter it is found that
the continuously oscillating generator produces
waves which become troublesome. Upon the key
ing signals is superposed a permanent tone when
heterodyne reception is used which tends to blur
the difference between dash and space or inter
vals. Inasmuch as in most instances, the fre
quency of the oscillation generator of the trans
mitter differs during spaces from that during a
dash, it may happen that the receiving station is
adjusted to space signals with the result that
negative signals are received.
In order to prevent this from happening the
The grid blocking voltages of the keyed sep~
arately-excited ampli?er or repeater stages and
the generator stage are derived from a joint volt-‘
age source by way of retarding means, the ratio
between the used and the least necessary block
ing voltage being chosen lower for the exciting (A
stage than for the separately excited stage.
The novel features of our invention have been
pointed out with particularity in the claims at
the end of the speci?cation. Our method of key
ing will be better understood from the following 10
description thereof and therefrom when read in
connection with the drawing in which Figures 1
to 5 inclusive show circuit diagrams which in
clude the essential elements for keying the gen
erator and. a stage of the transmitter ampli?er.
The idea upon which this invention is predi
cated shall be explained in more detail by refer
ence to the exempli?ed embodiment thereof
shown in Figure l of the drawing. i denotes the
tube of the exciting stage or initial generator, and 20
ampli?er or repeater or multiplier stages. How
ever, because of the “break” regions it is not pos
2 that of a separately excited stage which may
be an ampli?er; 3 and 4 denote grid coupling
coils, 5 and 6 grid blocking condensers, l and 8
grid direct current resistances; H3 is a keying re
lay which short-circuits potentiometer 9 at the 25
rythin of the Morse-code. With the relay being
sible to key it conjointly and simultaneously with
closed, the grid biasing voltage generator I 2 is
the main transmitter inasmuch as upon breaking
30 oil’ or resuming it would also cause shocks and
undesired signals in the excited transmitter am
pli?er stages or repeaters. For this reason re
course has been had to circuit arrangements com
prising a plurality of relays in which the genera
35 tor of the transmitter is disconnected only when
short-circuited upon the resistance H. The grid
direct current of the exciting or generator stage
?ows by way of parts BA and CA of the poten
tiometer 9 and the resistance 1 (which optionally
may be dispensed with) and results in the biasing
voltage for “upper” dash. In the separately ex
cited stage the grid direct current flows through
the key relay Ill and produces across the termi
nals of resistance 8 the biasing voltage for the
grid of tube 2 to amplify the upper dash. If,
then, the keying relay ill be opened, the capacity
6 will be charged by way of resistances 8 and H
7 generator of transmitter is keyed as well as the
the fall of signal in the transmitter ampli?er and
repeater stages has been completed; moreover,
the generator of the transmitter is re-connected
before the ampli?er becomes operative.
40
.
Now, the present invention dispenses with the
use of a plurality of relays and with the corre
so that a negative blocking voltage is applied to 40
sponding complicated relay and retarder circuit
the grid of 2. These currents in addition apply
a suitable biasing voltage to the grid of the pilot
tube 1 by way of the potentiometer Q and re
sistance ‘l and a charging potential of the con
means. In our invention the desired end, namely,
gentle keying of a separately excited transmitter
stage or stages and keying of the oscillation gen
erator is accomplished in such a manner that the
generator becomes disconnected or inoperative
only after completion of the decay of the wave in
the ampli?er and resumes operation prior to the
denser 5. By suitably choosing the resistances 8,
‘i, i i, ii, and of the capacities 6 and 5 the rise and
fall of the plate alternating current of both the
separately excited and the self-excited tubes is
building-up in operativeness of said ampli?er. _ in?uenced. By suitable adjustment of the slid
In our invention this is accomplished by the aid
of suitable circuit arrangements comprising elec
ing contact A of the potentiometer 9 conditions
50
can be made so that the tube 5 will be blocked
tric retarder means and a single key or a single v only after blocking'has been e?ected in tube 2,
standard keying relay. The principle underly
5.5. ing the invention is as follows:
and that tube I will be unblocked before tube 2
has been unblocked. In practice, of course, care 55
2
2,114,332
must be taken so as to provide proper choking,
especially in so far as the keying relay I0 is con
means connecting the control grid of the other
of said tubes to a different point on said ?rst
cerned, in order that the switching spark may not
give rise to audio frequency disturbances.
Another exempli?ed embodiment of the inven
tion is indicated in Figure 2. The plate voltage
and the grid biasing voltage are derived from a
joint voltage source It, the voltage being divided
by the resistances 9 and I5. In series with the
10 keying relay I0 generally is a resistance l3. Some
of the circuit elements l6, ll, l8, l9, under cer
tain circumstances, may be dispensed with.
If the form of the building up and decay of the
signal should not be perfectly satisfactory it is
possible by the insertion of choke-coils to insure
extensive changes in the shape of the signals.
named resistance, a reactance and a resistance
in parallel in one of said last named connections
and a circuit connecting the cathodes of both of
said tubes to a third point on said ?rst named
Two embodiments are shown in Figures 3 and 4.
In the case of Figure 3 there is disposed in series
with resistance 8 a choke-coil 20 with a parallel
resistance 2|; in Figure 4, a choke-coil 22 with
parallel resistance 23 is connected between ca
pacities 6 and 24.
In order that the duration of the rise and fall
of the signals may be varied independently of
one another, a recti?er is connected in parallel
relation to some of the elements so that these
elements become operative either only during the
rise or only during the fall of the signals.
One important embodiment is shown in Fig
iii) ure 5. In parallel relation to the capacity 6 is
a branch with condenser 25 and a resistance 26
in series, 25 being bridged or shunted by a de
vice 21, for instance, a dry recti?er. In the
exempli?ed embodiment here shown the recti?er
is so connected that it will be permeable or con
ductive in the direction of the arrow, that is,
upon discharge of the condenser. Then, during
the rise of the signal, the capacity 6 will be in~
creased by the capacity 25 and thus also the
time-constant and the length of the rise is in
' creased, whereas during the fall of the signal, if
capacities 8 and 25 and the resistance 26 are
suitably dimensioned, it is initially only the ca
pacity 6 and a smaller time-constant that become
operative.
Having thus described our invention and the
operation thereof, what we claim is:
1. A transmitter comprising a thermionic gen
erator tube, a thermionic ampli?er tube con
nected therewith, each of said tubes having a
grid and a cathode, means for keying said gen
erator and said ampli?er comprising a source of
direct current, a resistance in shunt therewith,
a connection between a point intermediate the
terminals of said resistance and the grid of said
generator tube, a connection between the oath
odes of said tubes and one terminal of said
source, a connection between another point on
said resistance and the grid of said ampli?er
60 tube, a resistance and a recti?er in parallel in
shunt to said ?rst named resistance, and a key
in shunt with said resistance.
2. A transmitter comprising a thermionic oscil
lation generator tube, a thermionic ampli?er tube
65 connected therewith to amplify the oscillations
generated by said generator tube, each of said
tubes having a control grid and a cathode, means
resistance.
3. An arrangement as recited in claim 2 in
which a condenser is connected between each
of the terminals of said parallel reactance and 10
resistance and the cathode of one of said tubes.
ll. A transmitter comprising a thermionic oscil
lation generator tube, a thermionic ampli?er tube
connected therewith to amplify the oscillations
generated by said generator tube, each of said
tubes having a control grid and a cathode, means
for keying said generator tube and said ampli
?er tube comprising a source of direct current
potential, a resistance and a condenser connected
in parallel with said source of direct current -,
potential, a key connected in parallel with said
source of direct current potential, resistive means
connecting the control grid of one of said tubes
to a point on said ?rst named resistance, resistive
means connecting the control grid of the other i
of said tubes to a different point on said ?rst
named resistance, a condenser connected between
the control grid and cathode of said ampli?er
tube, a recti?er connected in parallel with said
last named condenser and a circuit connecting
the cathodes of both of said tubes to a third
point on said ?rst named resistance.
5. In a telegraph transmitter, a transmitter
tube having input electrodes and having output
electrodes connected in a transmitter circuit, an ‘
exciting tube having output electrodes coupled
to the input electrodes of said transmitter tube,
a source of direct current, a direct current im
pedance connected with said source of direct
current, a key connected with said impedance 40
to control the potential drop produced across
said impedance by said source of direct current,
and means connecting points on said impedance
to said tube electrodes for rendering said excit
ing tube operative and then rendering said trans
mitter tube operative each time said key is placed
in marking position and for rendering said excit
ing tube inoperative after rendering said trans
mitting tube inoperative each time said key is
placed in the spacing position.
6. A telegraph transmitter as recited in claim
5 wherein said means includes additional direct
current impedances in series in said network and
current storing devices in shunt to said direct
current .network.
7. In a telegraph transmitter, a transmitter
tube having input electrodes and having output
electrodes connected in a transmitting circuit,
an exciting tube having output electrodes cou
pled to the input electrodes of said transmitter
tube, a source of direct current potential, an
impedance connected with said direct current
source, a key connected with said direct current
source and impedance for controlling the poten
tial drop produced in the impedance by said 65
direct current source, a direct current network,
including said impedance and key, connecting
said source of direct current potential to the
electrodes of said tubes to control the operative
tube comprising a source of direct current poten
70 tial, a resistance and a condenser connected in , ness thereotby controlling the direct current 70
potential supplied by said source to said elec
parallel with said source of direct current poten
tial, a key connected in parallel with said source trodes of said tubes, and additional impedance
means in said connections between said tube
of direct current potential, resistive means con
necting the control grid of one of said tubes to electrodes and said network cooperating with
75 a point on said ?rst named resistance, resistive said ?rst impedance and key for rendering said 75
for keying said generator tube and said ampli?er
2,114,332
exciting tube operative and then rendering said
transmitter tube operative each time said key is
in marking position and for rendering said ex
citing tube inoperative after rendering said trans
mitting tube inoperative each time said key is
placed in the spacing position.
8. A telegraph system as recited in claim 7
3
wherein said network includes current storing
devices in shunt to said network and additional
direct current impedances in series in said net
work.
RICHARD BRUCKNER.
RUDOLF GiiRTLER.
Документ
Категория
Без категории
Просмотров
0
Размер файла
393 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа