possible problem with Sony flat-face WEGA

Is that the same set you kept trying to give away on rec.antique.radio+phono?

Jeff

Are you kidding? That was an NAD MR-20A with a failing focus system.

It is a classic set, and worth restoring -- if you can find the parts needed (most likely a no-longer-available HOT system). If someone wants it, it's theirs for the cost of shipping.

Wait until it is a problem that doesn't go away after 2 seconds.

In other words, wait until an "intermittent" becomes permanent.

Definitely common sense -- but I'd rather make an end run around the problem.

Good luck.

William, the condition is usually caused by the crt cathode emission becoming weaker. When the picture no longer comes on, adjusting the screen control higher will allow the set to work for a few months to a year more. Chuck

I kinda expected that. If you're correct, it looks like I won't get my money's worth out of the set.

I wonder if anyone still makes CRT heater boosters. Remember those?

If they use DC on the fliament check for a bad electrolyytic in it's power supply. I used to add a filamnet transformer to series string TV sets with a dropping diode to power an 84 volt string of filaments. They barely lasted a year from new, without the modification.

Well, this set's over 10 years old. I'll pull out the service manual and give it a look.

CRT brighteners are still available but I wouldn't go that route until the screen control adjustment is no longer effective.

ice

it

de.

The industrial Sony's do a very similar thing as the CRT warms up. In those you're waiting for the beam current feedback to get up to speed. Since you have the service manual, is there anything in there about setting G2 by monitoring a specific set of lines in the vertical interval?

G=B2

I don't know; I haven't looked yet.

Is there any way to do that without reducing vertical scan?

Once you need a filament booster it's time to get the good old Sencore CR70 'Beam Builder' out of storage.

Or maybe just a bottle of Jim Beam?