On Monday, October 19, 2015 at 2:56:59 PM UTC-4, Jon Elson wrote:

Really, really, cheap timing lights, like from the J. C. Whitney of old,
were just two pieces of spark plug wire with a coiled neon tube in the
middle. The spark plug and the coil were the current limiter. They were
very dim, and you could get chopped up by the fan trying to get them close
enough to the timing marks to see anything.


That too. But a trigger electrode could also be down in the base somewhere.

Back when I drove carbureted VWs, I used a christmas tree light for a static timer. Seemed to work fine. I also had a neon timer such as you describe - and it had that big fat lens as in the pictures. The inductive lights did not. Might be as simple as a neon strobe head...

Peter Wieck
Melrose Park, PA