80 tube in Stromberg Carlson 130-H

2/16/2014 1:08:52 PMJack

Just picked up one of those radios. It works great. Ed Romney in his book, "Fixing up nice Old radios" on page 54-55, mentions that some replace the tube with 2 silicon diodes. to reduce heat and prolong the transfomer. he mentions a Dan Schultz in Florida that sells a plug in set to replace the 80.is he still in business? Thay way, I can preserve the 80 and the transformer.

2/16/2014 1:21:02 PMBrianC

Is your transformer running hot? If not, I wouldn't worry about the diode replacement tube. If you do choose a diode replacement for the 80, you must be sure there is a voltage dropping resistor, and some sort of delay, because you would be hitting the plates with full voltage before the tubes warm up with a SS replacement.

2/16/2014 1:29:53 PMJack

:Is your transformer running hot? If not, I wouldn't worry about the diode replacement tube. If you do choose a diode replacement for the 80, you must be sure there is a voltage dropping resistor, and some sort of delay, because you would be hitting the plates with full voltage before the tubes warm up with a SS replacement.
:
Thanks!

2/16/2014 3:06:29 PMCV

Delay probably doesn't matter much with the 80 tube. It is directly heated so it will start to pass current within a few milliseconds of turn on. Diodes will pass current even faster, but the point is that B+ will be up long before the rest of the set's tubes heat up anyway (since they are the indirectly-heated type). No tube current will flow until the other tubes' cathodes are hot enough to emit electrons, anyway, so no harm is done.

The dropping resistor is a good idea. It may not be needed, but it's good to check for overvoltage.

Connecting the diodes to replace the 80 tube is a snap. Take two 600V PIV 1 amp silicon diodes, solder the cathodes together, then solder this joined lead to either of the two heater pins of the 80 tube socket (your choice, doesn't matter). Then solder the anodes of the diodes to the plate terminals of the 80 tube socket (one to each). You can solder these parts under the chassis and put a cover over the empty socket, or you can find a defunct 4-pin tube, remove the bottle, and install the two diodes in the empty base.

80 tubes aren't very scarce, yet. Nearly every set that was made in the USA from 1929-1935 used them; some set makers used them for much longer.

2/17/2014 7:26:57 PMJack

:Delay probably doesn't matter much with the 80 tube. It is directly heated so it will start to pass current within a few milliseconds of turn on. Diodes will pass current even faster, but the point is that B+ will be up long before the rest of the set's tubes heat up anyway (since they are the indirectly-heated type). No tube current will flow until the other tubes' cathodes are hot enough to emit electrons, anyway, so no harm is done.
:
:The dropping resistor is a good idea. It may not be needed, but it's good to check for overvoltage.
:
:Connecting the diodes to replace the 80 tube is a snap. Take two 600V PIV 1 amp silicon diodes, solder the cathodes together, then solder this joined lead to either of the two heater pins of the 80 tube socket (your choice, doesn't matter). Then solder the anodes of the diodes to the plate terminals of the 80 tube socket (one to each). You can solder these parts under the chassis and put a cover over the empty socket, or you can find a defunct 4-pin tube, remove the bottle, and install the two diodes in the empty base.
:
:80 tubes aren't very scarce, yet. Nearly every set that was made in the USA from 1929-1935 used them; some set makers used them for much longer.
:
thanks, CV

2/20/2014 7:34:46 PMBill G.

::Delay probably doesn't matter much with the 80 tube. It is directly heated so it will start to pass current within a few milliseconds of turn on. Diodes will pass current even faster, but the point is that B+ will be up long before the rest of the set's tubes heat up anyway (since they are the indirectly-heated type). No tube current will flow until the other tubes' cathodes are hot enough to emit electrons, anyway, so no harm is done.
::
::The dropping resistor is a good idea. It may not be needed, but it's good to check for overvoltage.
::
::Connecting the diodes to replace the 80 tube is a snap. Take two 600V PIV 1 amp silicon diodes, solder the cathodes together, then solder this joined lead to either of the two heater pins of the 80 tube socket (your choice, doesn't matter). Then solder the anodes of the diodes to the plate terminals of the 80 tube socket (one to each). You can solder these parts under the chassis and put a cover over the empty socket, or you can find a defunct 4-pin tube, remove the bottle, and install the two diodes in the empty base.
::
::80 tubes aren't very scarce, yet. Nearly every set that was made in the USA from 1929-1935 used them; some set makers used them for much longer.
::
:thanks, CV
:
Hi Jack,
I have not used any of the diode replacement devices, however, I suspect they would have to have integral resistors, since they are meant to plug in as replacements for tubes.

I have heard a story that the type 80 had the record for the longest lived active electronic part, that it was in production from 1927 to 1975. I think some transistor or diode may pass it up soon.

Best regards,

Bill Girmm

2/20/2014 8:27:22 PMCV

:
: I have heard a story that the type 80 had the record for the longest lived active electronic part, that it was in production from 1927 to 1975. I think some transistor or diode may pass it up soon.

I would think that the 6V6 has earned the longevity award among tubes, since it was introduced in 1937 and is still being manufactured in Russia and China (to meet demand from the retro-guitar-tube-amp crowd).
However, it may have gone out of production for a span of time before being resurrected- I don't know. I would really like to see 45 tubes manufactured again- these were the staple medium-power radio audio output tubes before pentodes came on the scene, and audiophools have driven their prices sky-high in the past decade.

2/20/2014 8:35:35 PMBill G.

: :
:: I have heard a story that the type 80 had the record for the longest lived active electronic part, that it was in production from 1927 to 1975. I think some transistor or diode may pass it up soon.
:
:I would think that the 6V6 has earned the longevity award among tubes, since it was introduced in 1937 and is still being manufactured in Russia and China (to meet demand from the retro-guitar-tube-amp crowd).
:However, it may have gone out of production for a span of time before being resurrected- I don't know. I would really like to see 45 tubes manufactured again- these were the staple medium-power radio audio output tubes before pentodes came on the scene, and audiophools have driven their prices sky-high in the past decade.
:
Hi CV,
Well noted. The context for the 80 was continually produced. Also active component, too, since resistors of certain values have been in continuous production.

As I recall, 6V6GT went out of production in the 1960's. When did it come back?

Best regards,

Bill

2/20/2014 9:16:01 PMCV

: As I recall, 6V6GT went out of production in the 1960's. When did it come back?

Not sure that it ever really "went away", if you consider worldwide manufacturing. The communist bloc was around 15 years behind the west in abandoning tube technology in favor of solid-state devices. I can recall a Soviet pilot who defected in around 1974 along with the highest-tech jet fighter then in use in the USSR; the engineering team that analyzed it was astounded that its complex avionics suite was implemented entirely with vacuum tubes. No doubt their consumer electronics industry (such as it was) clung to vacuum tubes as well.

Presently 6V6 clones are being manufactured in Slovakia, Russia, and China. I bought some new Electro-Harmonix 6V6 tubes a few years ago, but I don't recall where they were made. They have a somewhat differently-shaped glass envelope than "classic" USA-made tubes, but they seem to work the same, at least in my Midwest KC-16.

2/21/2014 11:02:36 PMJohn K

:: As I recall, 6V6GT went out of production in the 1960's. When did it come back?
:
:
:Not sure that it ever really "went away", if you consider worldwide manufacturing. The communist bloc was around 15 years behind the west in abandoning tube technology in favor of solid-state devices. I can recall a Soviet pilot who defected in around 1974 along with the highest-tech jet fighter then in use in the USSR; the engineering team that analyzed it was astounded that its complex avionics suite was implemented entirely with vacuum tubes. No doubt their consumer electronics industry (such as it was) clung to vacuum tubes as well.
:
:Presently 6V6 clones are being manufactured in Slovakia, Russia, and China. I bought some new Electro-Harmonix 6V6 tubes a few years ago, but I don't recall where they were made. They have a somewhat differently-shaped glass envelope than "classic" USA-made tubes, but they seem to work the same, at least in my Midwest KC-16.
:

The 6V6 was created to power car radios, and spread from there to home radios and amplifiers, including the Fender Champ. Yes they are still being produced as is the 12AX7, another tube that has had a long run.

I'm trying to imagine breaking the sound barrier in a tube-powered Russian jet. Nope, I can't imagine doing that. :>)

2/22/2014 1:26:34 AMCV

Actually, it's only been in the last twenty years or so that the good old CRT has been replaced by LCD displays in USA aircraft cockpits, both military and civilian, rotary- and fixed-wing.

Vacuum tubes can be made exceedingly durable. The USA artillery shell proximity fuze of WW2 made use of tiny ruggedized vacuum tubes which were fitted into the end of the explosive projectile. These had to withstand hundreds of Gs during firing and remain undamaged. This tube-based fuze technology was classified for quite a few years after WW2 was ended, which is possibly why it is today a little-known piece of mil technology history.

2/22/2014 7:23:37 AMLewis

:
:
:Actually, it's only been in the last twenty years or so that the good old CRT has been replaced by LCD displays in USA aircraft cockpits, both military and civilian, rotary- and fixed-wing.
:
:Vacuum tubes can be made exceedingly durable. The USA artillery shell proximity fuze of WW2 made use of tiny ruggedized vacuum tubes which were fitted into the end of the explosive projectile. These had to withstand hundreds of Gs during firing and remain undamaged. This tube-based fuze technology was classified for quite a few years after WW2 was ended, which is possibly why it is today a little-known piece of mil technology history.

CV:
In the old days, the only CRT we had in the cockpit was the weather radar display.
Lewis
:

2/22/2014 8:24:32 AMCV

For me, the "old days" go back to the design phase years of the Boeing 757/767: late 1970s. The avionics maker where I worked as a digital design engineer had proposed (and Boeing had accepted) a proposal for a first-generation "glass cockpit" consisting of several color CRTs displaying flight profile and engine indication/control information. This was met with skepticism by many airline pilots, who felt that CRT displays would be subject either to abrupt failure or could present misleading info due to color shift (orange substituted for red, for example). At that time, electromechanical FPIs were the norm and EICAS was non-existent- engine management was achieved via the continuous scrutiny by a flight deck crew member of what seemed like a half acre of gauges.

As it turned out, the reliability of the color/BW CRTs was about an order of magnitude better than that of the complex electromechanical indicators that they replaced (although "backup" mechanical indicators were retained for many years alongside the bottle displays until Boeing finally dispensed with them altogether.)

After a very long run, these CRTs were displaced by LCD screen displays with fluorescent backlights, then by LCD screens with LED backlights. Eventually organic LED direct display will in turn displace these technologies in aircraft, just as they are starting to do in the commercial television market.

2/22/2014 10:39:01 AMLewis

:For me, the "old days" go back to the design phase years of the Boeing 757/767: late 1970s. The avionics maker where I worked as a digital design engineer had proposed (and Boeing had accepted) a proposal for a first-generation "glass cockpit" consisting of several color CRTs displaying flight profile and engine indication/control information. This was met with skepticism by many airline pilots, who felt that CRT displays would be subject either to abrupt failure or could present misleading info due to color shift (orange substituted for red, for example). At that time, electromechanical FPIs were the norm and EICAS was non-existent- engine management was achieved via the continuous scrutiny by a flight deck crew member of what seemed like a half acre of gauges.
:
:As it turned out, the reliability of the color/BW CRTs was about an order of magnitude better than that of the complex electromechanical indicators that they replaced (although "backup" mechanical indicators were retained for many years alongside the bottle displays until Boeing finally dispensed with them altogether.)
:
:After a very long run, these CRTs were displaced by LCD screen displays with fluorescent backlights, then by LCD screens with LED backlights. Eventually organic LED direct display will in turn displace these technologies in aircraft, just as they are starting to do in the commercial television market.

CV:
About the time that the 75/76 entered our fleet, I was transferred to a shop job (days only, weekends off, YAY!) so I didn't get to learn about the glass cockpits (we used Collins). I went from aircraft radio to electrical generation, worked on everything from the generators to the distribution busses. The 75/76 was the first digital generator control unit we ever saw, and we installed automated test equipment to test all of the seven or eight different airplanes we were flying at the time. (per-lenty of overtime in those days, working with three different companies on a new project, one that was new to everybody). Boeing uses a Sunstrand electrical system, different from anything we had ever seen before with a 8085 chip running the show for each generator. May I ask which avionics company you worked for? I have probably fixed some of your products.
Lewis
:

2/22/2014 10:53:51 AMCV

Rockwell Collins (successor to Collins Radio Company).

2/22/2014 11:34:26 AMLewis

:Rockwell Collins (successor to Collins Radio Company).

CV:
Delta just LOVED Collins black boxes. I did too, compared to soome of the others we got with the L-1011.
Lewis
:

2/22/2014 11:56:03 AMCV

For the most part, Collins products were quite well- designed. Some products (such as the FPC-75, an early terrain-approach warning system) were compromised by trying to build 1970s electronics in a 1960s factory that was in denial about static- discharge damage, but that got sorted out eventually. Personally, I am proud to have retired from their engineering staff.