[amron]

Hi
help will be appreciated. I have quite an old Linde(German) Tig welding machine. Its only problem is that its HF unit ceased to work and since it is so old it is next to impossible to fix it. I would like to ask if somebody can tell if it is possible to replace it with another unit (any kind - not the original).
it gets input of about 70vac and it delivers out a spark to ignite the arc.
Thanx.
Am

[Al_The_Man]

Should be able to adapt a Hypertherm HF unit.
If you have the one I am thinking of, they are similar in design (spark gap oscillator).
There is not much to them, are you sure it cannot be fixed?
Al.

[tadream]

All of the spark gap oscillator HF units are essentially the same. The capacitors, points, etc. are, for the most part, interchangeable. The vast majority of them use a xfmr with a 115v input. Your figure of 70v is kinda throwing me off a bit. Are you sure of that? Is it running off of weld OCV? Double check that, because that would be an unusual situation. A good choice would be Miller parts, as they are widely available, and cheaper than Lincoln, Hypertherm, etc. 208-045 is a part number for a HF xfmr with a 115 primary/3000 volt secondary. Capacitor would be 096-761. 199-854 is a spark gap assy. Should be all you need. BTW, most of the OEM parts should still be available. Linde is ESAB now. Hope this helps. Do you know specifically what parts are bad? Usually the capacitor is the culprit. I'd try replacing it first - with one of the Miller ones, and make sure the point gap is right. LMK how it goes.