The Use Of TV Sweep Tubes In RF Amplifiers
Home - Sweep Tubes In Power Amplifiers
The Use Of TV Sweep Tubes In Power Amplifiers
There is nothing wrong using horizontal sweep TV tubes being used in RF
power amplifiers. Some observations made by the author are given in this
article.
Doug DeMaw, W1FB.
The original article was published in the journal QST,
February 1980, pp.11…15
This webpage has had some information added, such as tube data from the
ARRL and information from my experience.
Some people are suspicious of using horizontal sweep TV tubes in power
amplifiers dues to their thermal "fragility", others claim that that such tubes
are not suitable for linear amplification. Of course, there is some truth in
these two statements, but these tubes also have many advantages! In any part
of the world, TV tubes are much easier to find than for an example, a 6146B
tube. This is undoubtedly a positive fact. It is also indisputable that TV sweep
tubes cost much less than, the 6146B.
In simple terms, the "Thermal fragility" problem can be explained by stating
the key down (continuous-carrier) is limited to short periods compared to that
of the 6146B or other transmitting tubes. Too long of a key down generally in
excess of 30 to 45 seconds will cause excessive tube heating and subsequent
damage or failure. The reason for this limitation is that sweep tubes are
designed for high peak currents of short duration (pulse service), but not for
high levels of continuous current. They are well suitable, for ICAS
(Intermittent Commercial Service) operation. In linear mode service, they do
not yield the IMD (Inter-modulation Distortion) quality which is typical of
6146B or other transmitting tubes at full rated power. In a properly designed
and operated amplifier, however it is possible to obtain sweep tube linearity
which comes near the 6146B. For example the Yaesu hybrid HF transceivers
used the 6JS6C for their amplifier section. The FT-101E which was reviewed
in September 1976 QST exhibited 3rd-order distortion products that were 34db down from full output. The Kenwood TS-820, which contains 6146B's in
the PA, was reviewed in the same issue. The 3rd order products from the TS820 were -39db below full power. The worst IMD observed in the ARRL lab
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The Use Of TV Sweep Tubes In RF Amplifiers
from a HF transceiver was which used sweep tubes was -27db. The ARRL
technical staff feels that an acceptable level for 3rd and 5th-order distortion
products (See Figure 1) is 30db or greater below full power. Therefore, the
FT-101 and the TS-820 transceivers are considered above average in terms of
IMD. Low Pass Filters such as the 100 watt Ebay kit can provide better IMD
of the kit, it also has relay
products on your output signal. This is a Circuit
and has extra circuit to switch bands using a 12vdc source. The now defunct
company Galaxy, once introduced a 2KW input power amplifier (Model 2000+
Photo Gallery)
and (Galaxy 2000 Plus Review)
that used 10 6HF5
horizontal sweep tubes connected in parallel. The amplifier worked in AB1
grounded cathode utilizing a non-inductive resistor in the input to the grids
for matching. The measured level of inter-modulation distortion of the 3rd
and 5th order in this multiple tube amplifier was rated at full output power 31db below the fundamental frequency.
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The Use Of TV Sweep Tubes In RF Amplifiers
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The Use Of TV Sweep Tubes In RF Amplifiers
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The Use Of TV Sweep Tubes In RF Amplifiers
I know this page was intended for sweep tube amplifier design, I figured on
describing these tubes a bit.The 807 was a 6.3 volt version of the 1625 had a
75 watt input at CW up to 60Mhz and was a beam power pentode not a tetrode
as every one describes on ebay. The next tube was the 6146 and this tube was
a upgrade to the 807, this tube was manufactured in 6.3, 12, and 26 volt
filament versions. The 6146B came a little later and was claimed by many
producers to be a drop in replacement to the 6146 provided the power supply
was able to give the input power demands. The 6146 had 90 watts input power
CW verses the 6146B at 120 watts input CW, but the B version was not
exactly the same as the older 6146 as RCA and others hoped for. The tube
had instability problems in the hybrid hf transceivers, including most of the
older rigs and heath kits (Glen E. Zook, K9STH was a Motorola technician in this
time period and he explains the 6146 Family of Tubes). The 811A is by far the
most popular tube in amateur radio history next to the 3-500Z, 3-1000Z. This
tube was originally designed to be used as modulators, and the 812 as the
finals in am transmitters. Hams later discovered the 811A tube to work very
well in ground grid class B service. This triumphed over the 812. The 811A
could work with 1250 plate volts with zero bias and 120 watts output, and 1500
plate volts with -4.5 bias. This higher plate voltage gave the 811A a output of
175 watts per tube, but can sacrifice tube life. Ameritron 811 and 811H has a
blistering 1700 volts on their 811A tubes and I think this is why a lot end up on
ebay as parts and repair. Some people do not drive them properly at these
plate voltages.
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The Use Of TV Sweep Tubes In RF Amplifiers
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The Use Of TV Sweep Tubes In RF Amplifiers
The electron tubes above were beam power pentodes, and three above were
sweep tubes except the 2E26. 6BQ6GTB, 6CD6G, and 6BG6GA. The 6BG6G
and the 6CD6G were shaped like the old 807 tubes. Then changes were made
to the tubes in the GA series such as shorter lead length inside the tube glass
to the socket. This helped the tube for RF amplifier work. The 6BQ6GAwas
similar to the 6BQ6GTB or GT, but had a larger glass circumference. The only
tube above that was not a TV sweep tube was the 2E26. This tube was a small
transmitting tube for HF and VHF frequencies. Link to a separate page of
various sweep tubes and Data.
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The Use Of TV Sweep Tubes In RF Amplifiers
The Popular 6146B Tube,
also in 12 and 26 volt
filament ratings.
6KD6
TV Sweep Tube.
Also in 30 and
36/40 volt
filament ratings.
Figure 1
Table 1
Some Sweep Tube Selections
Table 1
Tube
Type
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C (Input)
Pf
Input
Resonant
Frequency
(Mhz)
C (Output)
Pf
Output Resonant
Frequency (Mhz)
Probable***
Upper Frequency
Limit of
Operation (Mhz)
The Use Of TV Sweep Tubes In RF Amplifiers
6GJ5 (4)
6HF5*
6HF5**
6JB6
6JE6 (1)
6JM6 (2)
6JG6 (3)
19.1
25.5
26.7
19.1
24.3
17.2
22.9
190
86
100
190
82
200
187
10
16.3
16.3
10.5
14.5
10.3
14.7
190
141
141
200
152
194
226
150
60
75
145
60
150
150
One Grid Connection.
**Two Grid Connection.
***75 Percent of Self-Resonance Frequency.
(1) Electrically Identical to The 6LQ6 Tube.
(2) Electrically Identical to The 6GV5 Tube.
(3) Electrically Identical to The 6KV6 Tube and its Various Filament Variants.
(4) Electrically Identical to The 6DQ6 Tube and its Various Filament Variants.
Data: Courtesy of Sylvania Corporation
The data in the table was prepared by the company Sylvania.
Working Frequency
In fact horizontal sweep tubes give acceptable results up to about 30mhz.
Some of the smaller sweep tubes such as the 6JM6, 6GJ5, 6GV5, and 6JB6
give acceptable results up to 150Mhz, provided the input power to the plates
are reduced to a level the tubes can function without failure. The the 6146B
works up to 160Mhz with reduced input to the plate of about 50watts. The
limitation of the operating frequency range from some sweep tubes is caused
by the internal leads inside the tube connected to the pins of the socket.
Some sweep tubes such as 6DQ6, 6DQ5, 6BQ6GTB have internal leads that
are not suitable for frequencies above 30Mhz. Since these tubes were
designed for low frequency TV service to operate at 15.750Khz and provide a
trapezoidal waveform. The manufactures were not concerned with the
aforementioned "problem causers" The High terminal capacitances of the
tubes tend to shunt the RF currents to ground. This problem becomes more
pronounced as the operating frequency is increased. The high-input C makes
the tube hard to drive and presents impedance-matching problems. The high
output C can cause excessive currents inside the tube, causing gradual
performance degradation or complete failure. Therefore, it is wise to choose
sweep tubes with short internal leads and minimum terminal capacitance. The
effect of long internal leads is one of the lead inductance resonating, with the
internal capacitance at some specified high frequency. This condition can
cause stray RF currents to be high, ultimately harming the tube. VHF parasitic
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The Use Of TV Sweep Tubes In RF Amplifiers
oscillation is greatly enhanced greatly if the tube chosen has input and output
self-resonant frequencies which are close in frequency limits of the tube.
Table 1 below show how how various popular sweep tubes compare in this
nature. Parasitic chokes of the type shown in Figure 2 (Z1) can be installed to
reduce parasitic oscillations. A well fabricated chassis, Figure 2 with the input
and output section of the amplifier shielded from each other can also help in
stabilizing the tube circuit. Keeping input and output connections short as
necessary, can help in RF circuits.
Fig. 2 Schematic illustration of an amplifier
which contains a parasitic suppressor (Z1).
Figure 2
Details on the amplifier chassis Here!
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This component can be fashioned from a 47
to 100 ohm 2 watt pure resistive resistor.
Many claim metal oxide is not suitable, and
The Use Of TV Sweep Tubes In RF Amplifiers
inductive at radio frequencies, this is not
true. Resistor Facts. The copper wire is
wound over the resistor body and made to
connect to the resistor leads. 4 to 8 turns of
#20 enameled wire is suitable for the
suppressor. Another method of parasitic
suppression is a hairpin. Here!
A top view with tubes in their
sockets.
Front view
A chassis with (Figure 2. The Internal Shield) separating the input from the output section. This chassis
was fabricated for the 6DQ6B, 6JM6
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The Use Of TV Sweep Tubes In RF Amplifiers
One attempt to use a sweep tube at VHF. A 6JB6 was used for grounded-grid
operation and driven from a 5 watt exciter. An output of 25 watts was
obtained, but the tube efficiency was dismal- roughly 30 percent after
considerable optimizing. The tank circuit was designed to absorb the tube
output capacitance (Figure 3). The 19pf of input C presented no special
problem. Doug DeMaw, W1FB
Figure 3
Figure 4--Circuit of an experimental 144Mhz grounded grid amplifier
which used a 6JB6 sweep tube. C pf is the tube output capacitance.
L3 is dimensioned so that resonance occurs when C1 is set at 10pf.
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The Use Of TV Sweep Tubes In RF Amplifiers
The Problems of Parallel Use:
No matter which tube a builder may choose for the amplifier, paralleling two
or more such tubes creates design problems. A matter of special concern is
the current drawn by each tube plate in the circuit. Dynamic balance is
essential to ensure that no single tube in the circuit "out draws" the plate
current. If for example, six 6DQ6B's were connected in parallel, and the gm
(trans-conductance) of one was substantially higher than the rest, the one
with the high gm would probably be driven well beyond its safe dissipation
rating. The result would be disastrous as you set and watched the tube turn
red, just before the glass envelope melted or cracked. Sweep tubes are
especially prone to this ailment because their high gm ratings. The 6KD6, has a
trans-conductance of 14,000 micro-ohms! A not so practical solution to the
problem of current sharing is to install a matched set of tubes. Finding sweep
tubes and matching them is getting very difficult, cause there is no more
production, and what is left is surplus stock. For the amateur this is not good
news, as many tubes would be needed in order to grade them out for the
matched set required in the amplifier. A simple method for balancing the
tubes was worked out, by adjusting the bias on each tube using a separate
circuit. (Figure 4) With full drive to the amplifier, the bias adjust control for
each tube is adjusted for equal plate currents. The resting plate currents may
be unequal as a result, but they will not be too low to effect linearity of the
amplifier. Although separate meters are shown for each tube in figure 4, they
are not necessary. A single 0-1 ampere meter can be employed to measure all
four tubes at one time. Tube balance can be measured by installing a 10 ohm, 2
watt resistor in series with each cathode. R1 through R4 are then adjusted to
obtain equal voltages across the 10 ohm resistors at peak drive. When
choosing sweep tubes for grounded grid service Figure 4, it is mandatory to
select tube types which have the suppressor grid not connected internally to
the cathode. All of the grids should be returned to ground. Some sweep tubes
have their beam forming plates (suppressor grid) connected to the cathode
inside the tube. In grounded grid service this will lead to amplifier selfoscillation, especially as the frequency is increased. Another complication
which results from paralleling tubes is a increase in the combined input and
output capacitance. When these values become elevated, the greater the
unwanted RF-shunting effect discussed earlier. Severe limitations can be
imposed on the upper frequency range of the amplifier. The 6KD6 has a rated
input capacitance of 40pf and an output capacitance of 16pf. Six of these
tubes in parallel would yield 240pf input and 64pf output. The output
capacitance could be absorbed in the plate tank circuit, but the input
capacitance would have to be dealt with by means of matching network similar
to those used with RF power transistors. In fact, the plate impedance of
several sweep tubes in parallel become very low, causing the designer to move
in the direction of transistor matching networks. A six tube amplifier using
sweep tubes may develop up to 1 amp of current at peak drive. If the plate
voltage were 900 volts, A typical value for amateur service the plate
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The Use Of TV Sweep Tubes In RF Amplifiers
impedance would be 638 ohms, as calculated from RL = EP/1.57 x A.
Equation:
EP is the plate voltage.
RL is the plate impedance in ohms
A is the plate current for each tube
In basic terms, the low impedance and high output capacitance makes
conventional tank circuits impractical at frequencies above 40m. If a PI
network with a loaded Q of, 12 were desired, the resultant values of C and L
would become impractical at the upper end of the HF band. For this reason,
transistor types of matching networks become more desirable. Doug
DeMaw, W1FB
Another example of performance is the 6KD6, 6LB6, 6LR6 and 6KG6. (Doug
Demaw W1FB) designed and built a amplifier below using 6KD6 tubes. The RF
input is fed to the cathodes and the amplifier works in AB1 using adjustable
bias. The amplifier characteristics were observed on a spectrum analyzer. The
level of inter-modulation products were was -30db below the fundamental
frequency. The peak RF output of the amplifier was 800 PEP.
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The Use Of TV Sweep Tubes In RF Amplifiers
Figure 4-- A grounded-grid sweep tube amplifier which uses 6KD6 tubes. Dynamic
balance is ensured by means of R1 through R4. These potentiometers controls are set
to provide equal plate currents for the four tubes at peak drive periods.
(see text and note 1) This circuit originally appeared in July 1968 QST, page 31.
Sweep Tube Linear Amplifier Circuits
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The Use Of TV Sweep Tubes In RF Amplifiers
Links To Amplifier Circuits
2x4 RF Amplifier
4x6 RF Amplifier
PL519 150 RF Amplifier
PL519 QSK Linear Amplifier
PL519 4 Tube Linear Amplifier
A 6DQ5 Linear Amplifier (QST)
The Horizontal Output Linear (73 Amateur Radio)
A Cheap Pair Of Socks (73 Amateur Radio)
A Simple Fancy Linear (73 Amateur Radio)
The Novice 1/4 Gallon (QST)
A Sweep Tube Linear (ARRL Handbook)
A Sweep Tube Linear Amplifier (ARRL Handbook)
Galaxy 2000B 10-80Meter HF Amplifier
Kenrich Eagle 200 Amplifier
Kenrich Eagle 500 Base
Wawasee Blackcat Amplifiers
A little humor
Blackcat JB75 Mobile
Blackcat JB12 Base
Blackcat JB76 Base
Palomar Pulsar Mobile
Lafayette HA-250 Mobile
ABC 7107 Linear Mobile
ABC 250 Plus
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The Use Of TV Sweep Tubes In RF Amplifiers
D&A Hawk Base
D&A Maverick 250 Base
D&A Scorpion Mobile
D&A Hornet Base
D&A Raider Base
D&A Falcon 400 Mobile
D&A Bandit II Mobile
Maco 75 Duster
Maco 200 Base
Maco 300 Base
Maco 300 Mobile
Maco 750 Base
Maco Mini Brute Mobile
Golden Eagle 1k Base
Demco Demon 500 Plus Base
Demco Demon A500 Base
Demco Demon 250 Base
Demco Demon 50 Mobile
Demco Demon 50 Base
Courier ML100 Mobile
Courier BL100 Base
Kemtron Interceptor 101 Base
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The Use Of TV Sweep Tubes In RF Amplifiers
s
Figure 5 Schematic diagram of a 30Mhz amplifier circuit with meters for plate
current, screen current and grid current. This circuit can be adapted to work with
any of the tube types below. Z1 The parasitic suppressor used in figure 2, is the
same. L2 and L3 are chosen to provide a high operating tank Q. The input circuit can
be constructed from #14 enameled copper wire shown below. The builder can decide
on which is the best orientation for the input circuit. This is a common link input
circuit using the coax from the transmitter/transceiver as a tuning stub. It does not
matter which coax type you use rg58, rg8x or rg8u. Although rg58 would be my
choice for the benefit of flexibility. Details on making plate chokes can be seen Here
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The Use Of TV Sweep Tubes In RF Amplifiers
The neutralization capacitor must have specs that are designed for the RF power and
voltage of the plate. Another option would be to couple RF from the tube its self
back to the input circuit. This way the plate voltages would be negated in the
selection of the adjustable capacitor. The photo below shows a galvanized sheet of
metal for the neutralization circuit. The solder tabs will attach to standoffs,
phenolic or ceramic and a adjustable capacitor will be soldered to the plate with wire
(As short as possible) connected to the cold side of the input coil.
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The Use Of TV Sweep Tubes In RF Amplifiers
The above circuit is a typical grounded grid using TV sweep
tubes. Typical amplifiers on the market used 6LQ6, 6KD6,
6LB6, 6LF6 and 8950. A tuned input coil, seen in figure 6,
below was used in Maco, and some D&A amplifiers. Some of
the D&A had band switching 10 thru 40 meters. The Palomar
300A had 10 thru 40 meters and the amplifier worked well if
the internal bias was correct. Other amplifiers such as
Palomar used a T-68-6 toroid using 20 turns of 18# enameled wire
for matching.
Figure 6
I have over 100 of these link input coils for grounded grid
inputs on tubes such as 6kv6, 6jm6, 6km6, 6jn6, 6jn6, 6jb6,
6jg6, 6lb6, 6kd6 tubes. I spent hours on making these. There
made from solid copper and Teflon coated silver plated wire.
I'm asking $5.00 each, I can be contacted @ gmrs625@triad.
rr.com.
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The Use Of TV Sweep Tubes In RF Amplifiers
Elkin (Product Of Electronic Service Center)
These amplifiers in the beginning used 807, 1625 in a push pull design.
The amplifiers were made in 2, 4, 6, 8 tube versions and a 4x4 version
which was rare. The 4x4 amplifier used four 12dq6b driving four 8908's. The
8908's are now just about extinct unless anyone can find a hoarder that has
them on hand. The others had 12dq6b. There were no elkin 12 and 14 tube
those were built by a different group and looked similar in appearance, but
were not built by the same people. The company also made mobile amplifiers
too, using the 12dq6b and the 807 in very early models. Photos 1 and 2 show a
two tube Elkin using 6dq6b some people claimed the 12dq6b would deliver more
output power than the 6dq6b, but this is a false assumption the only
difference is the filament voltage. The Elkin as they were named operated in
grounded cathode, used tuned input by means of link input coupling. They were
stable amplifiers, if no one else would alter their circuitry. The amplifiers
were in fact hand made, and the color of the wire in the amplifier
corresponded to the person who wired each unit. These amplifiers had
excellent quality control when built and if you find one today I doubt it will be
original, cause other people tend to alter things. The power supply was unique
in these amplifiers verses other grounded cathode amplifiers. Other types of
amplifiers in grounded cathode turned the tubes on or off by use bias, the
Elkin turned the power supply screen, bias and plate off/on by using a relay to
switch the secondary full wave-bridge ground. This switched the whole
operating voltages off and on, except the filament. This was stressful on the
3rd pole of the relay over time. A schematic of a two tube base pictured
below shows the rf section, these amplifiers can operate on 10 meters and
give decent results on ssb IF the bias was adjusted correctly on a scope using
a two tone test. If a knowledgeable person wanted to operate these
amplifiers inside the amateur bands, lets say to 40 meters, this is possible
with the correct input and output.
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The Use Of TV Sweep Tubes In RF Amplifiers
Photo 1
Photo 2 (The tank output coil had extra turns to tune the
amplifier to lower frequencies)
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The Use Of TV Sweep Tubes In RF Amplifiers
Schematic of RF Circuit. Power supply not shown
Operating Parameters
In 1964, Sylvania Electric Products Inc.
Table 2
Class C Operation ICAS -- 30Mhz
Tube
Type
(1)
EG1
Vdc
(1) EG2 (1) Ep
Vdc
Vdc
Peak
EG1
V rf
(1) IG1 Ic2,
ma dc мА
Ia, мА Grid 1
Driving
Power
Watts
Grid 2
Dissipation
Watts
Plate
Input
Watts
RF
Power
Output
Efficiency
%
Plate
Dissipation
(2)
Circuit
Loss
Watts
6GJ5
-75
200
500
61
6.0
14.9
180
0.43
2.99
90.0
62.7
69.5
22.0
5.3
6HF5
-85
140
500
67
8.0
12.5
232
0.76
1.75
116.0
77.0
66.0
35.0
4.0
6JB6
-75
200
500
61
6.0
13.3
180
0.43
2.66
90.0
62.7
69.5
22.0
5.3
6JE6
-85
125
500
72
8.0
17.2
222
0.82
2.15
111.0
76.3
69.0
30.0
4.7
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The Use Of TV Sweep Tubes In RF Amplifiers
6JM6
-75
200
500
67
4.0
13.7
180
0.32
2.72
90.0
61.1
67.9
22.0
6.9
6JG6
-80
150
450
67
8.0
20.0
202
0.75
3.0
91.0
63.0
69.3
21.0
7.0
Efficiency
%
Plate
Dissipation
Watts
(3)
Circuit
Loss
Watts
41.5
43.0
41.5
42.6
43.1
43.0
22.0
35.0
22.0
30.0
22.0
21.0
3.0
2.7
3.0
2.6
2.2
4.1
Tube
Type
(1)
EG1
V dc
(2)
EG2
V dc
(2) Ep (1) Ip
V dc Zero
Signal
mA dc
6GJ5
6HF5
6JB6
6JE6
6JM6
6JG6
-43
-46
-42
-44
-42
-35
200
140
200
125
200
150
500
500
500
500
500
450
30
40
30
40
30
30
Table 3
Class AB1 Operation ICAS --30Mhz
IG2
Ip
Plate
Grid 2
Plate
RF
mA dc mA dc Power Dissipation Input
Power
Zero
Watts
Power Output
Signal
Watts Watts
Watts
3.8
85
15
0.76
42.5
17.5
4.5
133
20
0.63
66.5
28.8
4.2
85
15
0.84
42.5
17.5
3.9
110
20
0.49
55.0
23.4
4.4
85
15
0.88
42.5
18.3
4.5
98
13.5
0.67
44.0
18.9
Peak
Envelope
Power
(PEP)
Watts
35.0
57.6
35.0
46.8
36.6
37.8
ARRL Sweep Tube Operation
These data parameters were taken from the ARRL handbook,
SSB for the radio amateur. I will continue to update when I can
gather more information.
Filament
Plate
Screen
TransC
C
Class
Plate
Screen Grid
Screen Grid
Tube
(Heater)
Cgp
Socket
Plate
Driving Output
Dissipation Dissipation conductance
(Input)
(Output)
Of
Current Current Current
Type
6.3v/
pF
Base
Voltage Voltage Voltage
Watts Watts
mA
Watts
Watts
Micromhos
pF
pF
Service
mA
mA
Amperes
C
6DQ5
24
3.2
10.5k
2.5
23
0.5
11
8JC
600
150
-56
155
6
2
AB1
6DQ6B
18
3.6
7.3k
1.2
15
0.5
7
6AM
6HF6
6GC6
17
17.5
3.6
4.5
6k
6.6k
1.2
1.2
33
15
0.4
0.55
8
7
6AM
8JX
6GJ5
17.5
3.5
7.1k
1.2
15
0.26
6.5
9NM
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C
AB1
750
150
The Use Of TV Sweep Tubes In RF Amplifiers
6HF5
28
5.5
11.3k
2.25
24
0.56
10
12FB
6JB6
17.5
3.5
7.1k
1.2
15
0.2
6
9QL
6JE6
30
5.0
10.5k
2.5
24.3
14.5
9QL
6JG6A
17
3.5
10k
1.6
22
0.7
9
9QU
6JM6
17.5
3.5
7.3k
1.2
16
0.6
7
12FJ
6JN6
17.5
3.5
7.3k
1.2
16
0.34
7
12FK
6JS6C
30
5.5
2.25
24
0.7
10
12FY
6KD6
33
5.0
14k
2.85
40
0.8
16
12GW
6LB6
6LG6
30
28
5.0
5.0
13.4k
11.5k
2.25
2
33
25
0.4
0.8
18
13
12GJ
12HL
6LQ6
30
5.0
9.6k
2.5
22
0.46
11
9QL
6MH6
38.5
7.0
14k
2.65
40
1.0
20
12GW
G-G
G-G
500
800
0
0
0
0
85
150
6
12.5
25
82
G-G
800
0
0
150
12.5
82
G-G
G-G
G-G
800
0
0
150
12.5
82
800
0
0
150
12.5
82
G-G
800
0
0
150
12.5
82
Literature: Adobe 8.0 Reader
for those that don't have. Right click and save as.
I do not setup self executable files on my server.
1. DeMaw, “Some Ground Rules for Sweep-Tube Linear-Amplifier Design”,QST, July 1968, p. 30
2. DeMaw and Hayward, “Solid State Design for the Radio Amateur”, chapter 4, ARRL, 1977
3. DeMaw, “A Power Supply for That Big Linear Amplifier”, QST, December 1969
4. Transmitting Tube Guide
(If the page does not show the photo's click) Here for the PDF
5. "Simple Sine Wave Circuit" For alignment of SSB and AM modulation.
6. Hammond 200 Series Plate and Filament Transformers
7. Hammond 300 Series Plate and Filament Transformers
8. Hammond Plate Series Transformers
9. Excellent Article on Forced Air Cooling "Cool It"
10. Article on Designing Tank Coils. "Final Tanks"
11. 73 Article "Grounded Grid Filament Chokes"
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The Use Of TV Sweep Tubes In RF Amplifiers
12. 73 Article for scope monitor. "Linear Scope Monitor"
13. 73 Article on neutralization. "Neutralization"
14. ARRL Article "Oscilloscope Setups for Transmitter Testing"
15. 73 Article for helping you build a sweep tube amplifier. "Review of Grounded Cathode
Linears"
16. QST Article on Scope Patterns. "Sideband Scope Patterns"
17. 73 Article on Grounded Grid Amplifiers. "Some Notes On Grounded Grid Linear
Amplifiers"
18. ARRL Handbook. "RF Amplifier Component Ratings"
19. Excellent webpage on power transformer capabilities By WB0NNI. "Power
Transformer Capabilities"
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