Apple Multiple Scan 15AV CRT monitor repair

[tony359]

@electronic M
I do have a junker set with a smashed neck tube indeed! I'll go and find the thread, thanks.

@old_tv_nut
Thanks for the link - I am based in the UK, I'll see if I can find one of those but if I could re-use the coil from the other set that would be great as I don't normally work on CRTs.

I think I need to take a look at that 70V line though - PCBs can be inaccurate at times but the IC the line is driving says 80V VCC on the datasheet and I doubt the IC can work as expected with 30V - unless it's just a linear amplifier and that tube only needs an RGB p/p which can be achieved with 30V at the IC.

Also, I do not know whether by any chance there is some variable voltage regulation on the PCB which is tweaking that line - so maybe it's 30V now because it's set to 30V by the way the neckboard is set.
I think the first step would be to ascertain what kind of voltage is going INTO the regulators. If it's, say, 90V, then I know it's either a regulation issue or it's just being regulated to 30V by the various adjustments on the neckboard (which comes from another set so clearly misadjusted).

I'll keep you posted!