Neon and Mercury

[martin martin]

Greetings all,

These are no longer available in the US as of 40+ years ago. I found one in a box and had to put it back in to service!

They were sold as "silent switches".  Small tube of mercury to make the contact and the toggle switch has a large NE-2 for a nice looking night light.

[gregebert]

And these were also non-illuminated as well. In the early 1960's, my father swapped-out a few non-illuminated switches with the neon bulb version. Several years later, when  was about 11 years old, I found that stash of retired switches, took one apart, and was intrigued by the 'pellet' that was the actual switch. A friend and I determined it had mercury in it before we opened it, so we did some research before proceeding further. I was a bit afraid at first, having found out that mercury was used in explosives (fulminate), but after cracking open the first one we did the others. I still have that small batch of mercury in a glass bottle after nearly 50 years.

The pellets are metal on both sides, separated by glass or ceramic. As the pellet rotated, the mercury could flow thru a hole in the ceramic or glass separator and make electrical contact between the 2 metal sides. It was rather clever. Due to concerns about toxicity, as well as the rising cost of mercury, switches became mechanical-only. Some thermostats had a mercury bulb that made electrical contact.

[Nick Andrews]

Sweet!  I've been thinking of looking for a lighted switch in the 'on' position for the attic lights we installed to maybe remind us to turn them off.  Been up there a bit lately, running cable.  More cameras, power, commo.  New NVR has 10 cameras, I think have added about a dozen new duplex outlets, and so far 17 runs of cat5 through the house.  More to come.

Yes, some thermostats had mercury bulbs in them, the bigger ones having bigger bulbs.  I grab those wherever I can find them, getting scarce now.  There were also contactors with a fairly significant amount in them, but tricky to open for recovery.  OLD ignitrons I think had a large amount in them.  Sure mercury can be toxic, but it kills me to see the ridiculously idiotic overreactions to things like broken fluorescent bulbs in schools or places.  I know a guy who built a box device to try recovering the mercury from old bulbs.  It wasn't worth the hassle.  A 4' flo bulb has what, about 1/20 of a drop of mercury in it?  I've broken hundreds of them, and 8' ones too in my time.  In high school we used them for lightsabers at the university dump.

I use mercury in my carburetor sync gauge for my bike.  I know they make some now with a little tungsten rod in them which are safer, and maybe I'll buy one some day.  But for now, I'll hoard my little stash...

--
You received this message because you are subscribed to the Google Groups "neonixie-l" group.
To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/eab74d90-5a82-4b95-ac32-7d461e176485n%40googlegroups.com.

[alb.001 alb.001]

I make my own lighted switches...

I connect NE-2 lamps with a 20 K-ohm resistor at both ends of about 8 inches wire, drill a small hole in the switch face plate and push the end of the lamp thru just a little  and hot melt glue it in place. If the face plate is white, you can just glue the lamp to the backside of the faceplate and it will shine thru. I wire the other ends of the resistors to the hot and neutral terminals that go to the light.  When the light is off, the neon lamp lights, and when the light is on, the neon is off.  You can find all the light switches in my house at night just by looking for the neon glow.  They have never needed replacing.  If you want to be super safe, you can use 4 x K-ohm resistors,  two just next to the neon body and the other two at the other end of the wires. I use heat shrink over the resistor connections in both cases.   Very cheap and effective but not UL or CSA approved.

Pharma Phil 

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/CAJD4P-jHyrUMFQ3a1Mga9EcnLVJJmGZR8TATu0hqacdxBy7vfA%40mail.gmail.com.

 

[alb.001 alb.001]

that should say 4x 5 K-ohm resistors

sorry  Pharma Phil

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1046531948.7224121.1610758352346.JavaMail.open-xchange%40mtlgui09.

 

[Nick Andrews]

I've been thinking of doing exactly that,  with an INS-1, since I bought a hundred of them,  except I want the lamp on when the power is on so I'll hook it up to that side. 

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1046531948.7224121.1610758352346.JavaMail.open-xchange%40mtlgui09.

[Yohan Park]

The live and neutral terminals that go to the light?
There is no neutral in a switch, there's only a live wire and a switch wire.
If you're connecting the neon to these wires you're using the switch wire that goes to the lamp as your neutral.
That also explains why the neon turns off as soon as you turn on the light.

[David Pye]

Presumably also allows a small amount of current to leak to the light when the switch is off.

Largely irrelevant to incandescents but might well be enough to make led lamps glow slightly....

David

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1a0f90fb-e361-4d3e-885f-de2f9f6c4fb7n%40googlegroups.com.

[alb.001 alb.001]

sorry   I wire the neon lamp across the two terminals on the switch ( only works with one-way switches )

Pharma Phil

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/1a0f90fb-e361-4d3e-885f-de2f9f6c4fb7n%40googlegroups.com.

 

[Yohan Park]

Phil, sorry I'm getting back at this but I think you're seriously overdriving these NE-2 bulbs.
Even the high brightness versions need a 33K resistor.
Regular NE-2 bulbs (which you most likely use as well) require around 150K
I'm running standard brightness bulbs in my wall switches on 230V and I'm using 330K
Always go as high as you can with resistor value.
I've been running standard bulbs on 220K and they became luke warm to touch. This reduces the lifetime of the bulb and can cause blackening of the glass.

On Saturday, January 16, 2021 at 1:52:34 AM UTC+1 philthepill wrote:

[alb.001 alb.001]

Tohan

 I was taught to use 47 K resistors for NE-2 on 110 volts AC when I started back in 1975.   My lamps may be  NE-2 probably - I bought them in bulk at surplus stores and they are unmarked. I have had 8 running in my house since 1987 and none show any signs of darkening and I cannot detect any significant warming in any of them.   If I needed to redo them I could certainly use higher resistors, the brightness is not really greatly affected .   

Thanks   Pharma Phil

---------- Original Message ----------
From: Yohan Park <w...@kitsunegari.net>

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/4afbdd00-4926-4e50-8857-43e9f5d5c40cn%40googlegroups.com.

 

[alb.001 alb.001]

Yohan   sorry for misspelling your name.

Pharma Phil

---------- Original Message ----------
From: Yohan Park <w...@kitsunegari.net>
Date: January 23, 2021 at 7:10 PM

To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/4afbdd00-4926-4e50-8857-43e9f5d5c40cn%40googlegroups.com.

 

[Dekatron42]

There are many types/models of NE-2 neons, look at the table at the end of the book "Using and Understanding Small Neon Lamps" by William G Miller, might be in the files section on teh forum or can be downloaded from the internet, the list contains recommended resistor values for 115 VAC - the resistance value varies from 30k to 250k for the various models of NE-2.

/Martin

[gregebert]

From my Radio Shack education back in the early 1970's..........NE-2 bulbs required 220K when running off 120VAC line and used 1/25 watt. NE-2H (high-brightness) used a 22K resistor and used 1/4 watt.

---------------------------------------------------------------------------------------------

Sad fact.....I did not get into nixie tubes when they were cheaply and readily available at Radio Shack because I refused to believe a TTL device (74141) could tolerate the high-voltage used with nixies. Even the datasheet said the max voltage was 60V and I neglected the voltage-drop across the tube. That ignorance kept me away from nixies for roughly 35 years until I built my first clock from junkbox parts in 2011. Nope, I didn't use a 74141 in that clock and never will use them....