Andrew Back writes:

On Thursday, 6 March 2014 21:39:29 UTC, Samuel M. Goldwasser wrote:

One test to confirm it's the tube and not the power supply is to put a fan

on the tube. If it's the tube, that should enable it to stay lit at least

for a longer time.

I tried this and it didn't seem to have an effect. A write up of experiences so far, along with a few photos, can be found at:

http://designspark.com/eng/blog/brea...tage-gas-laser

(This assumes that the 3.7 kV value in the Laser FAQ is correct. It's from

the spec sheet but I have not measured a healthy one.)

This still has me wondering and in particular when I look at those old resistors and caps etc...

Helium ordered so will try a soak in any case.

Please keep us informed. If you have a spectrometer/monochromator you can
take a look at the discharge spectra and see if there are any O2/N2 linse,
and whether those two yellow He/Ne lines show up and are about equal in
intensity. See the Laser FAQ. ;-)

Possibly time to install a modern laser tube or head.

Never! )

Or a diode laser. ;-)

Ah come on, no one will know. "You're getting 250 mW from that head???".

--
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