A solid state replacement for the lowly 2D21 Thyratron tube...(sorry for the On-Topic post!)...

[bitrex]

On 4/21/2021 2:18 PM, John Larkin wrote:

On Wed, 21 Apr 2021 14:02:41 -0400, bitrex <user@example.net> wrote:

On 4/21/2021 1:53 PM, John Robertson wrote:
On 2021/04/21 10:48 a.m., bitrex wrote:
On 4/21/2021 1:28 PM, John Robertson wrote:
In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to
work on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s
used) on their very first control center for their Tormat (200 x
magnetic cores) memory and dropped it like a hot potato. There were
numerous service bulletins culminating in the factory providing a low
cost replacement for the control centers that used 2D21s (three of
these) and the replacement used a single 2050 tube and was a very
reliable design. Not everyone took advantage of the program and all
these replacement were used up long, long ago.

John :-#)#


What happens to them as they age? is that with respect to the unused
NOS types?

I was under the impression that small-signal gas thyratrons were very
reliable in service. They\'re much less temperature sensitive in
service than solid state devices, at least. If you blast a relaxation
oscillator made with a 2D21 with cold spray it barely drifts.

The 2D21 tubes become erratic, sometimes they respond, sometimes they
are slow (the solenoid grumbles as it sluggishly engages), and sometimes
they just ignore the control signal. Yet these tubes test OK on my
mutual conductance tube checker (of course).

John :-#)#


The tube tester can test for conductance from thermionic emission but
IDK if it can test for the conductance when the tube is operating in the
ionization-cascade mode.

A tube tester may not apply enough voltage or current capability to
fire the gas, so would miss a problem with ionization.

What\'s the Gm of a thyratron anyhow?

Thyratron anode conductance is grid current-controlled when in the
ionization mode, you can read off the parameters from fig 2 of the 2D21
datasheet. For grid 1 voltages between about -1 and -5 volts and Ib
between 25 and 200 mA it\'s vaguely linear at about 50mA per 1 mA.

One could build a simple thyratron tester.

 

[John Robertson]

On 2021/04/21 11:14 a.m., John Larkin wrote:

On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.

A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

The first control center is the original TSR1-L6, later it shows the
replacement control center the TSR3-L6.

You can ignore the stepper section, that is the interface to allow booth
boxes (called Wall Boxes in the industry) - but it doesn\'t matter unless
one is using those remote selectors...

Thanks for looking at this!

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[John Robertson]

On 2021/04/21 11:14 a.m., John Larkin wrote:

On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.

A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

The first control center is the original TSR1-L6, later it shows the
replacement control center the TSR3-L6.

You can ignore the stepper section, that is the interface to allow booth
boxes (called Wall Boxes in the industry) - but it doesn\'t matter unless
one is using those remote selectors...

Thanks for looking at this!

John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[John Robertson]

On 2021/04/21 11:19 a.m., bitrex wrote:

On 4/21/2021 2:14 PM, John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


The 1954 gear was probably designed to run on old-timey line voltage of
~110 AC. Dialing back the heater voltage on the thyratrons to compensate
for higher modern AC supply voltage might extend their life.

This controlled a solenoid at around 24VAC or regulated (0A2 = -150VDC)
power supply for the tormat write-in and readout circuits.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[ohg...@gmail.com]

On Wednesday, April 21, 2021 at 1:28:10 PM UTC-4, John Robertson wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

Designing a workaround would be easier from the standpoint of seeing exactly how it\'s wired in a circuit as opposed to making a general sub for that tube. Is there a schematic on-line anywhere?

 

[ohg...@gmail.com]

On Wednesday, April 21, 2021 at 1:28:10 PM UTC-4, John Robertson wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

Designing a workaround would be easier from the standpoint of seeing exactly how it\'s wired in a circuit as opposed to making a general sub for that tube. Is there a schematic on-line anywhere?

 

[Spehro Pefhany]

On Wed, 21 Apr 2021 12:44:37 -0700, John Robertson <spam@flippers.com>
wrote:

On 2021/04/21 11:14 a.m., John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

A thyratron is similar to an SCR, maybe a sensitive-gate type like
2N5064 could be made to work. This one is apparently Xenon-filled.

http://www.r-type.org/pdfs/2d21.pdf

https://www.mouser.ca/datasheet/2/308/2N5060_D-110409.pdf

I don\'t have the relationships of the thyratron grids in my head
though, never designed with one (I once fixed a spot welder that had
an enormous lethal-looking high voltage thyratron tube (cap on the
top) and a giant step-down transformer to give the kA pulse).
Hardly touched vacuum tubes after HS, for that matter.
--
Best regards,
Spehro Pefhany

 

[Spehro Pefhany]

On Wed, 21 Apr 2021 12:44:37 -0700, John Robertson <spam@flippers.com>
wrote:

On 2021/04/21 11:14 a.m., John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

A thyratron is similar to an SCR, maybe a sensitive-gate type like
2N5064 could be made to work. This one is apparently Xenon-filled.

http://www.r-type.org/pdfs/2d21.pdf

https://www.mouser.ca/datasheet/2/308/2N5060_D-110409.pdf

I don\'t have the relationships of the thyratron grids in my head
though, never designed with one (I once fixed a spot welder that had
an enormous lethal-looking high voltage thyratron tube (cap on the
top) and a giant step-down transformer to give the kA pulse).
Hardly touched vacuum tubes after HS, for that matter.
--
Best regards,
Spehro Pefhany

 

[bitrex]

On 4/21/2021 5:20 PM, Spehro Pefhany wrote:

On Wed, 21 Apr 2021 12:44:37 -0700, John Robertson <spam@flippers.com
wrote:

On 2021/04/21 11:14 a.m., John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

A thyratron is similar to an SCR, maybe a sensitive-gate type like
2N5064 could be made to work. This one is apparently Xenon-filled.

http://www.r-type.org/pdfs/2d21.pdf

https://www.mouser.ca/datasheet/2/308/2N5060_D-110409.pdf

I don\'t have the relationships of the thyratron grids in my head
though, never designed with one (I once fixed a spot welder that had
an enormous lethal-looking high voltage thyratron tube (cap on the
top) and a giant step-down transformer to give the kA pulse).
Hardly touched vacuum tubes after HS, for that matter.

Between the forces of good and the Evil Empire they must have made
bajillions of these things. Why OP not buy a gross from Russia? Just
sitting in their boxes in a dry environment the shelf life might be
measured in centuries.

<https://www.ebay.com/itm/274314016219?hash=item3fde63b5db:g:T38AAOSwgOpeqBXp>

 

[bitrex]

On 4/21/2021 5:20 PM, Spehro Pefhany wrote:

On Wed, 21 Apr 2021 12:44:37 -0700, John Robertson <spam@flippers.com
wrote:

On 2021/04/21 11:14 a.m., John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of these) and
the replacement used a single 2050 tube and was a very reliable design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

A thyratron is similar to an SCR, maybe a sensitive-gate type like
2N5064 could be made to work. This one is apparently Xenon-filled.

http://www.r-type.org/pdfs/2d21.pdf

https://www.mouser.ca/datasheet/2/308/2N5060_D-110409.pdf

I don\'t have the relationships of the thyratron grids in my head
though, never designed with one (I once fixed a spot welder that had
an enormous lethal-looking high voltage thyratron tube (cap on the
top) and a giant step-down transformer to give the kA pulse).
Hardly touched vacuum tubes after HS, for that matter.

Between the forces of good and the Evil Empire they must have made
bajillions of these things. Why OP not buy a gross from Russia? Just
sitting in their boxes in a dry environment the shelf life might be
measured in centuries.

<https://www.ebay.com/itm/274314016219?hash=item3fde63b5db:g:T38AAOSwgOpeqBXp>

 

[John Robertson]

On 2021/04/21 3:49 p.m., bitrex wrote:

On 4/21/2021 5:20 PM, Spehro Pefhany wrote:
On Wed, 21 Apr 2021 12:44:37 -0700, John Robertson <spam@flippers.com
wrote:

On 2021/04/21 11:14 a.m., John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson <spam@flippers.com
wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about 1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as nothing
seems to exist. These tubes are still available from several sources,
but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate bits of
electronic glue) to remove this tube from the suspect list when
servicing this classic Seeburg V200 jukebox would simplify future
servicing. I always like to make things easier for the next tech to
work
on machines that passed through my shop...

I should point out that Seeburg only used these 2D21s (three 2D21s
used)
on their very first control center for their Tormat (200 x magnetic
cores) memory and dropped it like a hot potato. There were numerous
service bulletins culminating in the factory providing a low cost
replacement for the control centers that used 2D21s (three of
these) and
the replacement used a single 2050 tube and was a very reliable
design.
Not everyone took advantage of the program and all these replacement
were used up long, long ago.

John :-#)#

Got a schematic? It might be easy.


A fairly recent scan (not tidied up) of my files section for the V200
Control Center:

https://www.flippers.com/pdfs/Seeburg_V200_Pg_5113-5143_B&W.pdf

Relevant schematic is on page 5128 (pg 16 or the PDF).

A thyratron is similar to an SCR, maybe a sensitive-gate type like
2N5064 could be made to work. This one is apparently Xenon-filled.

http://www.r-type.org/pdfs/2d21.pdf

https://www.mouser.ca/datasheet/2/308/2N5060_D-110409.pdf

I don\'t have the relationships of the thyratron grids in my head
though, never designed with one (I once fixed a spot welder that had
an enormous lethal-looking high voltage thyratron tube (cap on the
top) and a giant step-down transformer to give the kA pulse).
Hardly touched vacuum tubes after HS, for that matter.


Between the forces of good and the Evil Empire they must have made
bajillions of these things. Why OP not buy a gross from Russia? Just
sitting in their boxes in a dry environment the shelf life might be
measured in centuries.

https://www.ebay.com/itm/274314016219?hash=item3fde63b5db:g:T38AAOSwgOpeqBXp

Where\'s the fun in that? As I said, I know I can still get new tubes.
The problem is the system doesn\'t work well...

John ;-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[Edward Rawde]

\"John Robertson\" <spam@flippers.com> wrote in message
news:EKmdnXgYE4CpWx39nZ2dnUU7-Q3NnZ2d@giganews.com...
......

Between the forces of good and the Evil Empire they must have made
bajillions of these things. Why OP not buy a gross from Russia? Just
sitting in their boxes in a dry environment the shelf life might be
measured in centuries.

https://www.ebay.com/itm/274314016219?hash=item3fde63b5db:g:T38AAOSwgOpeqBXp

Where\'s the fun in that? As I said, I know I can still get new tubes. The
problem is the system doesn\'t work well...

I had a look at the pdf and the schematic looks like a typical work of art
from that era.

So you could probably get a solid state equivalent designed if you wanted to
pay a designer with the necessary experience to do it.
I\'m not offering but I\'d need the hardware in the same room as me to have
any chance.

John ;-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[Edward Rawde]

\"John Robertson\" <spam@flippers.com> wrote in message
news:EKmdnXgYE4CpWx39nZ2dnUU7-Q3NnZ2d@giganews.com...
......

Between the forces of good and the Evil Empire they must have made
bajillions of these things. Why OP not buy a gross from Russia? Just
sitting in their boxes in a dry environment the shelf life might be
measured in centuries.

https://www.ebay.com/itm/274314016219?hash=item3fde63b5db:g:T38AAOSwgOpeqBXp

Where\'s the fun in that? As I said, I know I can still get new tubes. The
problem is the system doesn\'t work well...

I had a look at the pdf and the schematic looks like a typical work of art
from that era.

So you could probably get a solid state equivalent designed if you wanted to
pay a designer with the necessary experience to do it.
I\'m not offering but I\'d need the hardware in the same room as me to have
any chance.

John ;-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John\'s Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
\"Old pinballers never die, they just flip out.\"

 

[server]

bitrex <user@example.net> wrote in
news:X0_fI.33919$wd1.30472@fx41.iad:

On 4/21/2021 2:14 PM, John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson
spam@flippers.com> wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about
1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as
nothing seems to exist. These tubes are still available from
several sources, but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate
bits of electronic glue) to remove this tube from the suspect
list when servicing this classic Seeburg V200 jukebox would
simplify future servicing. I always like to make things easier
for the next tech to work on machines that passed through my
shop...

I should point out that Seeburg only used these 2D21s (three
2D21s used) on their very first control center for their Tormat
(200 x magnetic cores) memory and dropped it like a hot potato.
There were numerous service bulletins culminating in the factory
providing a low cost replacement for the control centers that
used 2D21s (three of these) and the replacement used a single
2050 tube and was a very reliable design. Not everyone took
advantage of the program and all these replacement were used up
long, long ago.

John :-#)#

Got a schematic? It might be easy.


The 1954 gear was probably designed to run on old-timey line
voltage of ~110 AC.

110 VAC went away at the beginning of the 20th century. By 1950
120 Volts was the standard. The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

Dialing back the heater voltage on the
thyratrons to compensate for higher modern AC supply voltage might
extend their life.

The line voltage was already 120 Volts by then. You need a
remedial electrical system / electronics industry history course.

Or maybe you would simply develop enough Internet skills to know
how to use google properly.

 

[server]

bitrex <user@example.net> wrote in
news:X0_fI.33919$wd1.30472@fx41.iad:

On 4/21/2021 2:14 PM, John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson
spam@flippers.com> wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about
1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as
nothing seems to exist. These tubes are still available from
several sources, but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate
bits of electronic glue) to remove this tube from the suspect
list when servicing this classic Seeburg V200 jukebox would
simplify future servicing. I always like to make things easier
for the next tech to work on machines that passed through my
shop...

I should point out that Seeburg only used these 2D21s (three
2D21s used) on their very first control center for their Tormat
(200 x magnetic cores) memory and dropped it like a hot potato.
There were numerous service bulletins culminating in the factory
providing a low cost replacement for the control centers that
used 2D21s (three of these) and the replacement used a single
2050 tube and was a very reliable design. Not everyone took
advantage of the program and all these replacement were used up
long, long ago.

John :-#)#

Got a schematic? It might be easy.


The 1954 gear was probably designed to run on old-timey line
voltage of ~110 AC.

110 VAC went away at the beginning of the 20th century. By 1950
120 Volts was the standard. The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

Dialing back the heater voltage on the
thyratrons to compensate for higher modern AC supply voltage might
extend their life.

The line voltage was already 120 Volts by then. You need a
remedial electrical system / electronics industry history course.

Or maybe you would simply develop enough Internet skills to know
how to use google properly.

 

[Fox\'s Mercantile]

On 4/21/21 8:31 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:

110 VAC went away at the beginning of the 20th century. By 1950
120 Volts was the standard. The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

We go through this over and over again on the antique radio news
group.
110, 117, 120 = 120 vac


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[bitrex]

On 4/21/2021 9:31 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:

bitrex <user@example.net> wrote in
news:X0_fI.33919$wd1.30472@fx41.iad:

On 4/21/2021 2:14 PM, John Larkin wrote:
On Wed, 21 Apr 2021 10:28:02 -0700, John Robertson
spam@flippers.com> wrote:

In my field of arcade repairs we run into older jukeboxes - one
particular model which uses the 2D21 tube and was from about
1954.

I have the spec sheet here:

https://www.flippers.com/pdfs/2D21_Thyratron_tube.pdf

It would be fun to make a solid state replacement for it as
nothing seems to exist. These tubes are still available from
several sources, but they get wonky with age.

Being able to simply wire in a TRIAC or SCR (with appropriate
bits of electronic glue) to remove this tube from the suspect
list when servicing this classic Seeburg V200 jukebox would
simplify future servicing. I always like to make things easier
for the next tech to work on machines that passed through my
shop...

I should point out that Seeburg only used these 2D21s (three
2D21s used) on their very first control center for their Tormat
(200 x magnetic cores) memory and dropped it like a hot potato.
There were numerous service bulletins culminating in the factory
providing a low cost replacement for the control centers that
used 2D21s (three of these) and the replacement used a single
2050 tube and was a very reliable design. Not everyone took
advantage of the program and all these replacement were used up
long, long ago.

John :-#)#

Got a schematic? It might be easy.


The 1954 gear was probably designed to run on old-timey line
voltage of ~110 AC.

110 VAC went away at the beginning of the 20th century. By 1950
120 Volts was the standard. The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

Dialing back the heater voltage on the
thyratrons to compensate for higher modern AC supply voltage might
extend their life.

The line voltage was already 120 Volts by then. You need a
remedial electrical system / electronics industry history course.

But why when there are so many antiques available here to correct me

Or maybe you would simply develop enough Internet skills to know
how to use google properly.

Maybe you are so cranky all the time because yous are really easy to
manipulate into working for free.

 

[bitrex]

On 4/21/2021 10:42 PM, Fox\'s Mercantile wrote:

On 4/21/21 8:31 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:
110 VAC went away at the beginning of the 20th century.  By 1950
120 Volts was the standard.  The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

We go through this over and over again on the antique radio news
group.
110, 117, 120 = 120 vac

I\'m hearing that DLUNU would like to take responsibility for this
project and I think he\'s the best qualified based on his rebuttal. I
mean it\'s in his name. \"NumeroUno\"

 

[bitrex]

On 4/21/2021 10:42 PM, Fox\'s Mercantile wrote:

On 4/21/21 8:31 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:
110 VAC went away at the beginning of the 20th century.  By 1950
120 Volts was the standard.  The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

We go through this over and over again on the antique radio news
group.
110, 117, 120 = 120 vac

I\'m hearing that DLUNU would like to take responsibility for this
project and I think he\'s the best qualified based on his rebuttal. I
mean it\'s in his name. \"NumeroUno\"

 

[server]

bitrex <user@example.net> wrote in news:O36gI.7688$mO3.7546@fx09.iad:

On 4/21/2021 10:42 PM, Fox\'s Mercantile wrote:
On 4/21/21 8:31 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:
110 VAC went away at the beginning of the 20th century.  By 1950
120 Volts was the standard.  The MONIKER remained, but the voltage
has been 120 VAC for a VERY long time.

We go through this over and over again on the antique radio news
group.
110, 117, 120 = 120 vac



I\'m hearing that DLUNU would like to take responsibility for this
project and I think he\'s the best qualified based on his rebuttal. I
mean it\'s in his name. \"NumeroUno\"

In case you missed it, he was backing me up.