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NE3 neon bulbs in antique meter-what are they for?

E

Eric R Snow

Jan 1, 1970
0
Greetings All,
I was given an old meter that was originally bought by the US
government. It was missing some labeling so I don't really know yet
what all it can do. It can measure some kind of radio signal (I think)
because it has a probe that connects to the kind of fittings I've seen
on radio gear. The fittings are large co-axial and the probe plugs
into the fittings. The probe for this has some kind of tube (valve for
the Brits) in it with a metal point coming out of the end which makes
contact with what looks like a gold plated piece of bent flat spring.
I know this is not a very good description and I will be posting
pictures of it on the Metalworking.com web site. This device is about
6" x 9" by 8" tall. It had gotten wet so I took it apart to dry out
the internals. The meter movement seems to have stayed dry but other
stuff inside got wet. Inside the thing are two what I think are NE3
neon bulbs. The sockets for them are marked NE3. I was able to find
some on the internet for sale but no pictures. I have two questions
about these bulbs. First, since any light coming from these would not
be visible when using the meter what could their purpose(s) be? And
second, how can these bulbs be re-glued into their bases? I was going
to remove them from the sockets to clean the contacts in the sockets
but the glass bulbs are loose in the brass bases. I could buy new ones
but at anywhere from 9 to 15 bucks apiece, plus shipping, it's too
much money to spend on something that I don't know will even work when
plugged in. For that matter the meter is might release all it's magic
smoke when plugged in the first time. It's interesting that the power
supply section is made to be swung out when the case is removed from
the meter. Printed on the chassis inside are instructions to remove
two particular screws to pivot open the power supply.
Anyway, thanks for any help and insights.
Cheers,
Eric R Snow
 
R

Rheilly Phoull

Jan 1, 1970
0
Eric R Snow said:
Greetings All,
I was given an old meter that was originally bought by the US
government. It was missing some labeling so I don't really know yet
what all it can do. It can measure some kind of radio signal (I think)
because it has a probe that connects to the kind of fittings I've seen
on radio gear. The fittings are large co-axial and the probe plugs
into the fittings. The probe for this has some kind of tube (valve for
the Brits) in it with a metal point coming out of the end which makes
contact with what looks like a gold plated piece of bent flat spring.
I know this is not a very good description and I will be posting
pictures of it on the Metalworking.com web site. This device is about
6" x 9" by 8" tall. It had gotten wet so I took it apart to dry out
the internals. The meter movement seems to have stayed dry but other
stuff inside got wet. Inside the thing are two what I think are NE3
neon bulbs. The sockets for them are marked NE3. I was able to find
some on the internet for sale but no pictures. I have two questions
about these bulbs. First, since any light coming from these would not
be visible when using the meter what could their purpose(s) be? And
second, how can these bulbs be re-glued into their bases? I was going
to remove them from the sockets to clean the contacts in the sockets
but the glass bulbs are loose in the brass bases. I could buy new ones
but at anywhere from 9 to 15 bucks apiece, plus shipping, it's too
much money to spend on something that I don't know will even work when
plugged in. For that matter the meter is might release all it's magic
smoke when plugged in the first time. It's interesting that the power
supply section is made to be swung out when the case is removed from
the meter. Printed on the chassis inside are instructions to remove
two particular screws to pivot open the power supply.
Anyway, thanks for any help and insights.
Cheers,
Eric R Snow

The neons sound like static protection to the input (They fire on a voltage
of around 90v each) , mebbe it was used to measure RF ?
The glass tubes can be glued back into their bases with araldite or similar.
 
A

Art

Jan 1, 1970
0
Any way to post a photo of the device, maybe we could identify it a bit
easier, thx
 
B

Bob Masta

Jan 1, 1970
0
The neons sound like static protection to the input (They fire on a voltage
of around 90v each) , mebbe it was used to measure RF ?
The glass tubes can be glued back into their bases with araldite or similar.

I've also seen this neon threshold exploited for use as a voltage
regulator. And because it takes less voltage to maintain the
discharge than to start it, neons were sometimes used to
make simple relaxation oscillators.

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Home of DaqGen, the FREEWARE signal generator
 
E

Eric R Snow

Jan 1, 1970
0
I've also seen this neon threshold exploited for use as a voltage
regulator. And because it takes less voltage to maintain the
discharge than to start it, neons were sometimes used to
make simple relaxation oscillators.

Best regards,


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Home of DaqGen, the FREEWARE signal generator
Thanks to all of you who posted answers to my meter questions. I will
post pictures on the Metalworking.com web site in a couple days. I'll
post the link here when they show up.
ERS
 
J

John Jardine.

Jan 1, 1970
0
Eric R Snow said:
Greetings All, [...]
Eric R Snow
Sounds like an R.F. millivoltmeter. The probe containing a rectifier diode
type valve that gives a DC out proportional to the RF voltage at the
connector.
With small RF signals, the DC out may only be a few mV and could be the
reason for the neons.
They are possibly used in conjunction with a couple of CdS photocells to
'chop up' the DC (at a low frequency) to allow easy AC amplification and
finally drive the meter.
john
 
E

Eric R Snow

Jan 1, 1970
0
Eric R Snow said:
Greetings All, [...]
Eric R Snow
Sounds like an R.F. millivoltmeter. The probe containing a rectifier diode
type valve that gives a DC out proportional to the RF voltage at the
connector.
With small RF signals, the DC out may only be a few mV and could be the
reason for the neons.
They are possibly used in conjunction with a couple of CdS photocells to
'chop up' the DC (at a low frequency) to allow easy AC amplification and
finally drive the meter.
john
Greetings John,
Your description matches this device. It has mills, DC, and Ohms. The
NE3 bulbs do not have any CdS photocells associated with them. I
powered up the device and only one of the two neon bulb lights up.
There tubes, I think electrolytic capacitors, and one power
transistor in this thing. Do you know if it would be worthwhile to try
to make it work again? The meter movement itself seems fine. Is it
maybe something that a radio person could use? And is worth the cost
of shipping? It is just a curiosity to me.
Thanks,
Eric R Snow
 
J

John Jardine.

Jan 1, 1970
0
Eric R Snow said:
Eric R Snow said:
Greetings All, [...]
Eric R Snow
Sounds like an R.F. millivoltmeter. The probe containing a rectifier diode
type valve that gives a DC out proportional to the RF voltage at the
connector.
With small RF signals, the DC out may only be a few mV and could be the
reason for the neons.
They are possibly used in conjunction with a couple of CdS photocells to
'chop up' the DC (at a low frequency) to allow easy AC amplification and
finally drive the meter.
john
Greetings John,
Your description matches this device. It has mills, DC, and Ohms. The
NE3 bulbs do not have any CdS photocells associated with them. I
powered up the device and only one of the two neon bulb lights up.
There tubes, I think electrolytic capacitors, and one power
transistor in this thing. Do you know if it would be worthwhile to try
to make it work again? The meter movement itself seems fine. Is it
maybe something that a radio person could use? And is worth the cost
of shipping? It is just a curiosity to me.
Thanks,
Eric R Snow

Eric. G'day.
Sadly, I'd say it sounds like it's a junker. Great value and benefit in
it's time but now outpriced, outperformed, outgunned.
The neons look like they're there as voltage stabilisers. Beyond that, the
meter is the only bit worth saving.
Over the years I've found I can't even give this kind of stuff away and had
to scrap tons of it.
All of it magnificently engineered, using the finest materials and doubtless
classics in the making. Would need though a secure warehouse and another 40
years of careful ageing and TLC :)
john
 
E

Eric R Snow

Jan 1, 1970
0
Eric R Snow said:
Greetings All,
[...]
Eric R Snow
Sounds like an R.F. millivoltmeter. The probe containing a rectifier diode
type valve that gives a DC out proportional to the RF voltage at the
connector.
With small RF signals, the DC out may only be a few mV and could be the
reason for the neons.
They are possibly used in conjunction with a couple of CdS photocells to
'chop up' the DC (at a low frequency) to allow easy AC amplification and
finally drive the meter.
john
Greetings John,
Your description matches this device. It has mills, DC, and Ohms. The
NE3 bulbs do not have any CdS photocells associated with them. I
powered up the device and only one of the two neon bulb lights up.
There tubes, I think electrolytic capacitors, and one power
transistor in this thing. Do you know if it would be worthwhile to try
to make it work again? The meter movement itself seems fine. Is it
maybe something that a radio person could use? And is worth the cost
of shipping? It is just a curiosity to me.
Thanks,
Eric R Snow

Eric. G'day.
Sadly, I'd say it sounds like it's a junker. Great value and benefit in
it's time but now outpriced, outperformed, outgunned.
The neons look like they're there as voltage stabilisers. Beyond that, the
meter is the only bit worth saving.
Over the years I've found I can't even give this kind of stuff away and had
to scrap tons of it.
All of it magnificently engineered, using the finest materials and doubtless
classics in the making. Would need though a secure warehouse and another 40
years of careful ageing and TLC :)
john
That's what I thought. It has a really nice bakelite case. Maybe I'll
keep that part if I can't find someone who would like the whole thing.
ERS
 
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