My ILT is *flashing* at startup. whats causing this?
When I was at SoCaLem this last weekend, I acquired thru a trade, an ILT 5490A.
I got it home & powered it up & it started the first try. I let it run for a couple hours not knowing when the last time it had been run. The next night when I ran it, I let it run at the *recommended* max current level & let it run for 2 hours. The next night it flashed about 8 times(igniter pulses) then lit. I ran it at idle for 5 hours. the next night it had a harder time igniting. It took 30 pulses to get it to ignite. I let it run for 5 pulses each time before turning off the key & resting it for a few seconds. I read on Sams that the tubes don't like the start pulse as it blows off chunks of the cathode filament each time it fires. It now is having a harder time starting taking up to a minute to start.
What is causing the tube to be hard starting? the fan is a squirrel cage fan ,the same one I used on my 60 X, sucking air out thru the top. The cooling is adequate, I believe, unless I really need the patriot or Comair-Rotron pancake fans.
Is this a sign that the tube is at high pressure? Or is at end of life? Is the start current set too low? What is the cost of re tubing an ILT? And finally, if I use a violet wand from the early 1900, will it fry the starter card in the head & items in the power supply if I use it to start the tube.
Thanks,
Nate.
Last edited by Vidal Wolf; 02-13-2011 at 18:13.
Reason: Punctuation.
Will there be three phase!!!!