If you use the regulator as a reference in a"series" regulated supply, it's noise gets gained up by the error amplifier.
Last time I used a gas regulator was for the screen supply in a ham radio transmitter.
Gas Discharge Tubes as voltage references?
Hmmm...reading an old book on neon lamp references & regulators, I had the hare-brained idea of investigating gas discharge tubes sold for transient protection.
No socket required, take up less room than OC3, OD3, etc., but no visible color glow to enhance one's chassis, maybe noisy like Zener & VR tube...wide range of voltages starting at 28 V breakover, into the hundreds or thousands.
I feel the need to try some experiments...
Has this ever come up before? It seems to be off-label as far as current manufacturers are concerned. I may have to find a local physicist to ask as I think a support request to Littelfuse, TDK, etc. would be misunderstood.
Thanks
Murray
Hmmm...reading an old book on neon lamp references & regulators, I had the hare-brained idea of investigating gas discharge tubes sold for transient protection.
No socket required, take up less room than OC3, OD3, etc., but no visible color glow to enhance one's chassis, maybe noisy like Zener & VR tube...wide range of voltages starting at 28 V breakover, into the hundreds or thousands.
I feel the need to try some experiments...
Has this ever come up before? It seems to be off-label as far as current manufacturers are concerned. I may have to find a local physicist to ask as I think a support request to Littelfuse, TDK, etc. would be misunderstood.
Thanks
Murray
Data for protection is readily available.
Gas Discharge Tubes | Low Surge GDTs | Medium Surge GDTs - Littelfuse
"GDT Products Catalog"
What I see: the break-over voltage is much higher than the glow voltage, and very loosely specified. This in contrast to ordinary lamps and regulators where the break-over voltage is held as low as practical. So you need a "lot" of excess voltage to be sure one will start. (In many regulator plans, if the gas tube does not start, output goes to maximum, which may be bad.)
The glow voltage seems to be very poorly specified. Some parts say 140V with no tolerance. One says ~~60V-200V, a wide range. (I don't think a 28V job is gas-tube.)
There is NO power rating for long-term glow. Since these are pencil-eraser size and moreover have only a 90 deg C temp rating, the safe power must be quite small.
They do not GLOW. Ceramic packages etc. To me this is a deal-breaker.
However they are one-buck parts. Buy a few and juice them up. Probably learn more in an hour that way than 2 hours on the phone IF you can keep an applications engineer on the line that long (for an off-label application in quantity one-or-two).
Gas Discharge Tubes | Low Surge GDTs | Medium Surge GDTs - Littelfuse
"GDT Products Catalog"
What I see: the break-over voltage is much higher than the glow voltage, and very loosely specified. This in contrast to ordinary lamps and regulators where the break-over voltage is held as low as practical. So you need a "lot" of excess voltage to be sure one will start. (In many regulator plans, if the gas tube does not start, output goes to maximum, which may be bad.)
The glow voltage seems to be very poorly specified. Some parts say 140V with no tolerance. One says ~~60V-200V, a wide range. (I don't think a 28V job is gas-tube.)
There is NO power rating for long-term glow. Since these are pencil-eraser size and moreover have only a 90 deg C temp rating, the safe power must be quite small.
They do not GLOW. Ceramic packages etc. To me this is a deal-breaker.
However they are one-buck parts. Buy a few and juice them up. Probably learn more in an hour that way than 2 hours on the phone IF you can keep an applications engineer on the line that long (for an off-label application in quantity one-or-two).
Glow discharge is condition under which voltage across the tube is stable. VR tubes have broad range of glow discharge current (5-30 or 5-40 mA), making them useful for voltage regulation.
By contrast, overvoltage protection tubes have very narrow current range of glow discharge. As current increases, glow discharge is replaced by arc discharge.
By contrast, overvoltage protection tubes have very narrow current range of glow discharge. As current increases, glow discharge is replaced by arc discharge.
Yeah, I got mixed messages re: voltage stability depending what parameter or datasheet I chose, but that could happen on any given day!
On my list...as well as some dead CFL's I habitually pry apart (used to 'design', or manipulate existing electronic ballast designs for other lamps at a job in the 90's...my quotes around 'design'). It was never the 'tube' that died, always some miserable little under-rated component I'd find acquired a pinhole, black spot, or empty space between leads). I have a lamp databook somewhere...little spiral bulbs probably have 35-55 V across them with an obnoxious glow level for chassis use...and hard to mount when all that's left are the pigtail leads.
The 48, 60 & 96" lamps have higher plasma voltages but dimensionsal incompatibility confront my enthusiasm.
I asked my local bizarre phenomena physicist about the GDT's and he smirked & said they MIGHT glow inside.
This is why I have difficulty finishing projects ��
On my list...as well as some dead CFL's I habitually pry apart (used to 'design', or manipulate existing electronic ballast designs for other lamps at a job in the 90's...my quotes around 'design'). It was never the 'tube' that died, always some miserable little under-rated component I'd find acquired a pinhole, black spot, or empty space between leads). I have a lamp databook somewhere...little spiral bulbs probably have 35-55 V across them with an obnoxious glow level for chassis use...and hard to mount when all that's left are the pigtail leads.
The 48, 60 & 96" lamps have higher plasma voltages but dimensionsal incompatibility confront my enthusiasm.
I asked my local bizarre phenomena physicist about the GDT's and he smirked & said they MIGHT glow inside.
This is why I have difficulty finishing projects ��
The data I skimmed suggested arc starts near 0.5 Amps, a number he is unlikely to approach (or not for long!).
There is also a minimum glow current, below which the surface thermal losses exceed the volume power input, and glow collapses.
Made-For VR tubes set both extremes to reasonable points, as you say. Tubes made to take HUGE SHORT spikes really do not care about the glow mode, agreed.
But it's a buck experiment. He should do it and report back.
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