Hi, all concerned:

What's the nomenclature for that sweep tube, produced just for Admiral TVs
years ago, that's heavier-duty than any of the other tubes?

I thought it was 6MJ6 -- but, no.

Fella used to sell 'em in some of the mid-west hamfests, but I haven't seen
him for a while. Think his name is Don, and that he was also in to Racal
receivers.

TIA & 73

Behold, David J Windisch signalled from keyed 4-1000A filament:

Hi, all concerned:

What's the nomenclature for that sweep tube, produced just for Admiral
TVs years ago, that's heavier-duty than any of the other tubes?

I thought it was 6MJ6 -- but, no.

Fella used to sell 'em in some of the mid-west hamfests, but I haven't
seen him for a while. Think his name is Don, and that he was also in to
Racal receivers.

TIA & 73

I know the Sylvania 6LF6 tubes, custom made for Motorola were heavier
duty - rated 50 watts Pa continuous........

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

Gregg wrote in message news:4XtJc.56662$eO.20724@edtnps89...
Behold, David J Windisch signalled from keyed 4-1000A filament:

Hi, all concerned:

What's the nomenclature for that sweep tube, produced just for Admiral
TVs years ago, that's heavier-duty than any of the other tubes?

I thought it was 6MJ6 -- but, no.

Fella used to sell 'em in some of the mid-west hamfests, but I haven't
seen him for a while. Think his name is Don, and that he was also in to
Racal receivers.

TIA & 73

I know the Sylvania 6LF6 tubes, custom made for Motorola were heavier
duty - rated 50 watts Pa continuous........

6JS6 is the number that emerges from the cobwebbed long term memory -
used a lot in Yaesu stuff as pa tubes, ie 101's. Cheaper than 6146's
in those days, now the situation is reversed so the old rigs are being
modified to 6146's Unless you have boxes of them stashed away, dont
design anything around them, a long obselete technology...
73 de VK3BFA Andrew

PS - I have several dozen 807's in the junk box, will use them one
day.....

Andrew VK3BFA wrote:
Gregg wrote in message news:4XtJc.56662$eO.20724@edtnps89...

Behold, David J Windisch signalled from keyed 4-1000A filament:


Hi, all concerned:

What's the nomenclature for that sweep tube, produced just for Admiral
TVs years ago, that's heavier-duty than any of the other tubes?

I thought it was 6MJ6 -- but, no.

Fella used to sell 'em in some of the mid-west hamfests, but I haven't
seen him for a while. Think his name is Don, and that he was also in to
Racal receivers.

TIA & 73

I know the Sylvania 6LF6 tubes, custom made for Motorola were heavier
duty - rated 50 watts Pa continuous........


6JS6 is the number that emerges from the cobwebbed long term memory -
used a lot in Yaesu stuff as pa tubes, ie 101's. Cheaper than 6146's
in those days, now the situation is reversed so the old rigs are being
modified to 6146's Unless you have boxes of them stashed away, dont
design anything around them, a long obselete technology...
73 de VK3BFA Andrew

PS - I have several dozen 807's in the junk box, will use them one
day.....

807's are becoming pricey these days. Still some cheap 1625's
available though. There must have been a google of them made
during WWII.

....[snip]....
807's are becoming pricey these days. Still some cheap 1625's
available though. There must have been a google of them made
during WWII.

After reading an article about building an amplifier which used ten 1625's
with paralleled RF but with series filaments directly across the 120-volt
line, I've been saving them; hope to find the right round tuit someday....

--Myron.
--
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448
NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol)

That's similar to my ideas, which include doubling the 240V mains to 600V to
put on the plates. an isolation xfmr would be needed for the filaments, tho.

600V at 4-5A would give a ballpark of 50 ohms plate resistance, low enough
for no-tune techniques.

Still haven't found that tube # tho ;o)

73, Dave, N3HE

SNIP
After reading an article about building an amplifier which used ten 1625's
with paralleled RF but with series filaments directly across the 120-volt
line, I've been saving them; hope to find the right round tuit someday....
SNIP

Behold, David J Windisch signalled from keyed 4-1000A filament:

600V at 4-5A would give a ballpark of 50 ohms plate resistance, low
enough for no-tune techniques.

Still haven't found that tube # tho ;o)

Parallel a few 6080's ;-)

--
Gregg t3h g33k
"Ratings are for transistors....tubes have guidelines"
http://geek.scorpiorising.ca

wrote:
....[snip]....

807's are becoming pricey these days. Still some cheap 1625's
available though. There must have been a google of them made
during WWII.


After reading an article about building an amplifier which used ten 1625's
with paralleled RF but with series filaments directly across the 120-volt
line, I've been saving them; hope to find the right round tuit someday....

--Myron.
Reminds me of an amp using a bunch of sweep tubes in parallel running
off the mains with a voltage quadrupler to get 600 volts.

With the 1625's there is a trick the old timers used to do.
Some brands of 1625's (I do not know which) had the beam deflection
electrodes ("grid" 3) brought out of the glass bulb with it's
own lead wire. (You might be able to see this upon close inspection
of the tube if the silver getter isn't in the way.)
The cathode and "grid" 3 were connected together
at the base pin. So what you did was to un glue and un solder
the base and then bring "grid" 3 out to it's own pin (there are
two un used pins on the 1625 base). This lets you run the 1625 in
grounded grid (cathode driven). Use 10 tubes, 9 in parallel as
the final, and the 10th as a driver stage. You now have a two
stage linear that will run about 500 watts out with less than
5 watts drive. The tube heaters could be run in series across
the mains, and use a voltage quadrupler to get 600 volts for the
plate supply. Use of an isolation transformer would be a very
good idea though!

After reading an article about building an amplifier which used ten
1625's
with paralleled RF but with series filaments directly across the
120-volt
line, I've been saving them; hope to find the right round tuit
someday....
=================================
Considering that with so many valves (tubes) in parallel operation the
inter-electrode capacitance is multipled accordingly, it would be
intriguing
to know up to which frequency this set-up could be sensibly used.


I have seen a CB amp using as many as 12 of the 1625 tubes. There were 6 in
parallel on each side of a push pull circuit. Not sure how clean the output
was but they seemed efficiant enough to give about 300 to 500 watts out of
carrier power and the modulation sounded good.

After reading an article about building an amplifier which used ten 1625's
with paralleled RF but with series filaments directly across the 120-volt
line, I've been saving them; hope to find the right round tuit someday....
=================================
Considering that with so many valves (tubes) in parallel operation the
inter-electrode capacitance is multipled accordingly, it would be intriguing
to know up to which frequency this set-up could be sensibly used.

I have quite a number of 'never used' 807s in the junkbox , pardon me
.........NOS box.

Frank GM0CSZ / KN6WH