Predicta Holiday power-up

[rickfray]

I'm getting close to powering up my Predicta that I've been working on. What are the best practice procedures for powering up to avoid damage?

I've replaced all the paper caps and resistors out of tolerance

I put a fuse and small power resistor in series in place of the fusible link that was missing

Replaced 2 missing tubes

CRT has tested good

I have an isolated variac to power it up

Power it up without tubes or the CRT connected? Not sure if no tubes at all does anything to look for shorts elsewhere?

Then power up with just the vacuum tubes installed and no CRT? Check if all filaments lit? Does it makes sense to check all the voltages on the tubes at this point before connecting the CRT?

Thanks

Rick

[bandersen]

First try powering it up with the fusible link removed and all the tubes installed. That way you will only have power going to the tube filaments.

It's a series filament set so you have to either have the CRT connected or use a power resistor to replicate it's filament. If all the tubes light up, then I'd put the fusistor back in and go for a full power up.

Good luck!