Can anyone identify N1 and N2 for me?
Not from a car BTW just from a controller circuit board but I have not seen these components before.
TIA
I think I might have tracked them down?
https://uk.rs-online.com/web/p/led-indicator-lamps/6559413/?cm_mmc=UK-PLA-DS3A--google--CSS_UK_EN_Lighting_Whoop--Neon%20Indicator%20Lamps_Whoop--6559413&gclid=Cj0KCQjw6s2IBhCnARIsAP8RfAjR-SzkMivqAV00CIIOsddAAU1ZT8Kvv2Mpy_obZrJHRzTQrzBhJ8kaArebEALw_wcB&gclsrc=aw.ds&matchtype=&pla-357839864043
Think grumpy is on the money. What is the pcb for?
Those are a pair of neon bulbs.
They are often used as voltage references, OR random noise generators. I assume the two resistors are wired in series with them as a current limit to protect them. They were the valve-era equivalent predecessor to the zener diode.
Those look well past it with a lot of metal transferred to the inside of the glass envelope.
Depending on the construction, (ie electrode metal, dimensions and proportions of gas mix inside) the conduction voltage across them could be designed to be anything from 50V to 150V for each one.
These are usually applied in a DC circuit when a regulator or a protector. Those look like they have been run near their current limit for a long time.
However, I have seem a stack of them in an AC circuit as a spike arrester to protect a mains transformer primary winding when the power was switched OFF (ignition coil effect over-volting the winding insulation, now use an MOV which is much better).
See the wiki for more info
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That’s some great knowledge thank you it’s really appreciated.
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It’s part of a control unit for an electric fence apparently 
a friend send the pic and asked me if I knew what they were but it’s nothing I had come across before. I am impressed with @RichardFX explanation very thorough and informative.
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Yes, he’s a clever chap is Richard, helped me loads when tinkering with my retro audio gear! 
Barrie
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Neons will light up over 90v, I expect these are to regulate the voltage or ensure it does not go over 90v or 180v if wired in series.
Roy
PS … AC voltage, they are arc devices that will arc/light up over a set voltage. Often also used to show mains powered devices are switched on. e.g. washing machines, fridges, test screwdrivers etc. A tad old fashioned these days but stil used and available.
Roy
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I love a teaser, thanks all that’s the great thing about this club the wealth of knowledge and willingness to help, keeps your faith in humanity!
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