UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Other Discussions > Homebrew Equipment

Notices

Homebrew Equipment A place to show, design and discuss the weird and wonderful electronic creations from the hands of individual members.

Closed Thread
 
Thread Tools
Old 1st Dec 2016, 11:41 pm   #1
Warmsteel
Retired Dormant Member
 
Join Date: Oct 2012
Location: Castletown, Isle of Man
Posts: 44
Default Neon Bulb ignition timing light

Greetings all

I wonder if anyone would know the internal workings of the early (80's) neon bulb engine timing lights as opposed to the xenon 12 volt powered timing lights?

I have done many searches in an attempt to find a circuit diagram but it seems that there aren't any diagrams posted anywhere on the net, that I can find.

I would be grateful to anyone who could possibly help me as this would help me in my other hobby, vintage engines.

Thank you

John
Warmsteel is offline  
Old 1st Dec 2016, 11:53 pm   #2
DangerMan
Heptode
 
Join Date: Jul 2009
Location: Stoke-on-Trent, Staffordshire, UK.
Posts: 719
Default Re: Neon Bulb ignition timing light

I have one of the old neon type.

It is simply a large spiral glass tube with an electrode at each end, and with low pressure neon gas filling.
In other words, just a big neon lamp.
Connected directly (in series) between the spark plug lead and the spark plug it is energised directly by the ignition coil pulse.

There are no other internal electrical components, just a well insulated housing, a white plastic "reflector" for the neon tube, and a clear plastic lens.
DangerMan is offline  
Old 2nd Dec 2016, 12:24 am   #3
Bazz4CQJ
Dekatron
 
Bazz4CQJ's Avatar
 
Join Date: Apr 2009
Location: Oxfordshire, UK.
Posts: 4,924
Default Re: Neon Bulb ignition timing light

As above, it's just a neon and a resistor and the problem with them is just the lack of light output. I struggled with a neon timing light for years (adequate in most but not all instances) and when I finally treated myself to a xenon lamp the difference was like night and day.

B
Bazz4CQJ is offline  
Old 2nd Dec 2016, 12:29 am   #4
paulsherwin
Moderator
 
paulsherwin's Avatar
 
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,787
Default Re: Neon Bulb ignition timing light

I have one too, though I haven't used it in over a decade. I finished up using it at night with the garage lights turned off - it certainly wasn't usable in daylight.
paulsherwin is offline  
Old 3rd Dec 2016, 5:31 pm   #5
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: Neon Bulb ignition timing light

This thread has been reopened.

PLEASE STAY ON TOPIC
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is online now  
Old 3rd Dec 2016, 5:36 pm   #6
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: Neon Bulb ignition timing light

I have one of these units. There's nothing inside it except a neon lamp.

It is useless. You can only see the output in the dark, so it's a case of using it at night, or in a darkened garage with the attendant risk of CO poisoning.
Attached Thumbnails
Click image for larger version

Name:	IMG_9786.jpg
Views:	224
Size:	30.6 KB
ID:	133767  
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is online now  
Old 3rd Dec 2016, 6:11 pm   #7
Refugee
Dekatron
 
Refugee's Avatar
 
Join Date: Apr 2012
Location: Worksop, Nottinghamshire, UK.
Posts: 5,549
Default Re: Neon Bulb ignition timing light

I once made one out of an ordinary neon lamp and it did work.
It had to be taped onto the indicator flag by the pulley in order to get it close enough to work at all.
I can't remember if I wired it in series with the HT or connected it across the points.
Refugee is offline  
Old 3rd Dec 2016, 6:50 pm   #8
Warmsteel
Retired Dormant Member
 
Join Date: Oct 2012
Location: Castletown, Isle of Man
Posts: 44
Default Re: Neon Bulb ignition timing light

Thank you gentlemen

Your input so far has been invaluable but firstly would anyone know if the large spiral bulbs or tubes as mentioned by danger man are still available and if so what would the technical term be?

It seems like there are a few versions about as Bazz4CQJ mentions a resistor with a neon bulb, would this be a NE-2 bulb or something different and would the resistor be in series or parallel?

Moderator, Station X, has a different version of a bulb which is further intriguing, from my point of view, as I am now not sure what to make of all the variations?

I have seen some pictures of different bulbs, like the coiled version but my dad had a very small, about 60mm long by about 20mm in diameter which produced an orange glow that would vary in intensity depending on the strength of the HT and this is what I would really like to home brew.

I like Refugee's idea and I have tried a NE-2 bulb with a resistor but the bulb didn't last long, perhaps it is the incorrect configuration or the wrong value of resistor, any thoughts anyone?

Either way, I do appreciate everyone's continued input.

Thank you

John

P.s. I appreciate the daylight and other problems etc, but please, lets keep this to the circuit and on topic as advised by the moderators.

Thank you again
Warmsteel is offline  
Old 3rd Dec 2016, 10:21 pm   #9
Bazz4CQJ
Dekatron
 
Bazz4CQJ's Avatar
 
Join Date: Apr 2009
Location: Oxfordshire, UK.
Posts: 4,924
Default Re: Neon Bulb ignition timing light

I have never opened mine up and my comment that there is a resistor in there is really speculative, assuming it would be in series with the neon to extend lamp life, but I guess it could be that with the quite limited use these things see, maybe a resistor isn't absolutely necessary? Of course, most HT leads are resistance cables anyway to achieve noise suppression.


What is the make of your model and does it look easy to open up?

B
Bazz4CQJ is offline  
Old 3rd Dec 2016, 10:41 pm   #10
Radio Wrangler
Moderator
 
Radio Wrangler's Avatar
 
Join Date: Mar 2012
Location: Fife, Scotland, UK.
Posts: 22,800
Default Re: Neon Bulb ignition timing light

The neon runs on the current in the HT lead. Most HT leads are resistive anyway - about 20k Ohms as an interference suppression measure. There isn't a resistor in a neon timing light, they want to minimise the voltage drop.

Unfortunately the light output is rather poor and the things need shoving in close to the timing marks usually on front pulleys. People put their heads in close and fingers in... all close to whirling fans. Plenty of accidents were attributable to dim timing lights.

I used the Crypton system's xenon light at dad's garage. Mains powered and only triggered by the HT to number 1 plug, with a calibrated delay to measure advance curves etc. Bright and much safer

David
__________________
Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
Radio Wrangler is online now  
Old 3rd Dec 2016, 10:52 pm   #11
Warmsteel
Retired Dormant Member
 
Join Date: Oct 2012
Location: Castletown, Isle of Man
Posts: 44
Default Re: Neon Bulb ignition timing light

Hi Bazz4CQJ

Attached is a photo my Dad sent me but he tells me that there isn't any makers information on it other than "Made in England". He also informs me that the handle, for want of a better description, is fairly hard rubber and appears to have been moulded around the internals and attempting to open it would probably destroy it, which he is reluctant to do, so hence my query.

It has two leads, one that apparently connects to the HT lead and the other to the plug so somehow it is in series but exactly how is a mystery.

I have yet to see one which could be opened to see the internals but these seems few and far between these days.


Thanks again

john
Attached Thumbnails
Click image for larger version

Name:	Neon Timeing light.jpg
Views:	245
Size:	192.4 KB
ID:	133780  
Warmsteel is offline  
Old 3rd Dec 2016, 11:15 pm   #12
Warmsteel
Retired Dormant Member
 
Join Date: Oct 2012
Location: Castletown, Isle of Man
Posts: 44
Default Re: Neon Bulb ignition timing light

With the risk of running slightly off topic, perhaps I should give a better description of my intended use?

Whilst I have referred to "it" as a neon timing light I don't actually intend to use it to time anything I am working on but rather I am intending to use it to determine the health of the HT coil from magnetos and further troubleshooting in that regard.

I realize there are better means of testing a HT coil or secondary coil, inductance, resistance etc, but as a quick, efficient and easy means to determine HT, a little neon timing light is just the job, I am reliably informed.

Thanks again

John
Warmsteel is offline  
Old 4th Dec 2016, 12:46 am   #13
Oldcodger
Nonode
 
Join Date: Oct 2014
Location: West Midlands, UK.
Posts: 2,181
Default Re: Neon Bulb ignition timing light

Quote:
Originally Posted by Station X View Post
This thread has been reopened.

PLEASE STAY ON TOPIC
Thank you , Graham.
I made one out of a GPO cold cathode- HT CABLE to car HT Lead/ plug and a decent sized resistor between Anode and Grid to get it to fire.

Problem was ,as RW says- fingers too close to pulley belts to see marks, so I decided on a Xenon tube( Radio Shack, UK ) . Supply needed was 240v DC- so I decided on a TL494 circuit , driven from a pulse transformer with inputs tacked onto the HT leads. Light output- great, but ,it's horribly inefficient.
Circuit is available for anyone that wants it. As per another thread. I'm trying to update it so my SIL( for those that can't work out stuff that =Son In Law) can se it to set up bike Timmy.
Oldcodger is offline  
Old 4th Dec 2016, 2:21 am   #14
Bazz4CQJ
Dekatron
 
Bazz4CQJ's Avatar
 
Join Date: Apr 2009
Location: Oxfordshire, UK.
Posts: 4,924
Default Re: Neon Bulb ignition timing light

I think there are perhaps two issues here; (i) the interest in restoring/preserving your dad's vintage made in England timing lamp (of which I ain't seen one like that before) and (ii) the requirement for a useful lamp(s) for everyday use.

Firstly, I cannot see anywhere where John says it does not actually work. So let's go right back to basics re the vintage lamp. At the of one lead should be a tapered tin sheath which should click nicely into the inside of a plug cap, specifically the No1 plug cap. The other wire should have a tin sheath which clicks nicely over the No 1 spark plug. Now, ensure the wires are clear of all moving bits, and when you start the engine and look at the lamp, does it flash; if so, it works. And if that's the case, I would store it somewhere safe and cherish it.

Now if you want a simple "universal neon lamp", note that if you search around, there were some big neon lamps made in the past (see attached); handy if you just want to test a coil or a magneto etc.

But, when it comes to setting timing on a running engine, for about £18, you can get a wonderfully bright and safe xenon lamp. The very popular model which I have is shown here http://www.ebay.co.uk/itm/AccuSpark-...8AAOSwkl5XcoDm, and is available from several online sources.

I still have my old neon lamp, which served me well for over 30 years, but have totally pensioned it off.

B
Attached Thumbnails
Click image for larger version

Name:	P1020005.JPG
Views:	173
Size:	148.6 KB
ID:	133782  
Bazz4CQJ is offline  
Old 4th Dec 2016, 7:57 am   #15
dseymo1
Retired Dormant Member
 
Join Date: Dec 2007
Location: Shropshire, UK.
Posts: 3,051
Default Re: Neon Bulb ignition timing light

The type with which I am familiar can be opened up quite easily.
The lens is held in place by a wire circlip, and it in turn holds the neon tube in the handle moulding. That's all there is to it - remove the circlip and lens, and the tube can be withdrawn. The wires simply follow tubular guide holes in the handle.
If you want a neon timing light, there's at least one on eBay at the moment. I expect they come up regularly.
dseymo1 is offline  
Old 4th Dec 2016, 10:34 am   #16
richrussell
Heptode
 
richrussell's Avatar
 
Join Date: Jul 2008
Location: Selby, North Yorkshire, UK.
Posts: 979
Default Re: Neon Bulb ignition timing light

I've got one similar to the one above - here's a closeup of the coiled neon.

I have to admit I got given this one when my father in law was clearing out his garage, but found it no good during daylight hours - even the light leaking in under the garage door swamped the reflection of the neon on the pulley. So I got a cheap Gunson's xenon one and the neon one's never been used since.
Attached Thumbnails
Click image for larger version

Name:	IMG_1562.JPG
Views:	188
Size:	107.4 KB
ID:	133786  
richrussell is offline  
Old 4th Dec 2016, 1:34 pm   #17
AC/HL
Dekatron
 
AC/HL's Avatar
 
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,637
Default Re: Neon Bulb ignition timing light

Quote:
Originally Posted by Warmsteel View Post
Whilst I have referred to "it" as a neon timing light I don't actually intend to use it to time anything I am working on but rather I am intending to use it to determine the health of the HT coil from magnetos and further troubleshooting in that regard.
In the intended application many of the drawbacks, well the one main drawback, visibility, can probably be accommodated.
AC/HL is offline  
Old 4th Dec 2016, 2:26 pm   #18
russell_w_b
Dekatron
 
russell_w_b's Avatar
 
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,684
Default Re: Neon Bulb ignition timing light

I used the xenon tube from an old flashgun in a disposable camera to prove the presence of a 1us 1750V pulse from a Marconi ignitron pulse unit (followed on the real thing by a 150ms 200V 'sustain' pulse).

It worked a treat, just electrode-to-electrode: no need for the trigger electrode to be used. I mounted it in one of those little plastic drawers for components where the top fits snugly over the bottom.

Perhaps you could use one?
__________________
Regds,

Russell W. B.
G4YLI.
russell_w_b is offline  
Old 4th Dec 2016, 2:56 pm   #19
Guest
Guest
 
Posts: n/a
Default Re: Neon Bulb ignition timing light

They have two main problems, the light pulse is a bit long giving a fuzzy mark. And as said quite dim, not too bad on an enclosed engine (like a motorcycle one) where the timing marks are under a cover (it's dark in there with no fan to chop ones fingers off).

I do wonder if the fuzzy pulse (covering the whole spark time) is more representative of when the petrol vapour is ignited as opposed to a xenon one where the light flash is at the start of the spark. All in all they are interesting bit of kit from the days when us mere mortals had a chance of fixing things and had access to the manuals telling us what to do. One reason I like vintage radios.
 
Old 4th Dec 2016, 3:06 pm   #20
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: Neon Bulb ignition timing light

The OP has made it clear that he doesn't intend using the unit to check timing, but rather to check the HT from magnetos.

This seems pointless to me. All you have to do is hold the HT lead close to the engine block and check that you get a spark.
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is online now  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:41 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.