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Quote:

Originally Posted by miniman82 (Post 2856575)

Just started work on the Halolight I got from Mark (zenithfan1), it's a model 377 which has a dark cabinet with double doors.

Chassis produces a raster after replacing one bad rectifier so I'll recap it, but the halolight light tube is shot. Don't suppose there's any way to revive one of these, is there? The supply has enough power to light up a 40 watt bulb from my ceiling, but nothing from the tube in the set. The tube will light up if I hit it with whatever voltage is going to the picture tube from the high voltage supply, so it does work if you get enough juice to it. My guess is it's gonna be either find a way to get more voltage to the tube, or have a new one made at a neon sign place or something like that? Could there possibly be spares???

Have you checked the pair of 33Meg resistors feeding the light? They may have drifted significantly upward.

Quote:

Originally Posted by WISCOJIM (Post 2862194)

Have you checked the pair of 33Meg resistors feeding the light? They may have drifted significantly upward.

I tried bypassing them completely (and the control), and connected the light directly to the transformer secondary- got nothing. :no: There's a member on ARF who says he has a complete Halolight setup for me, so if that falls through it's off to the sign shop.

I did think of another thing though. What if you wrapped a thin wire around the tube, like they do with xenon camera flashes. Maybe if you fed that with some RF, it would encourage the light to work? It will come on briefly if you cycle the power switch on the set, which I attribute to either voltage spikes or RF.

there is a guy in Pa near Pittsburg that has a halolight tv chassis and light assembly , i can foward his information to ya

If he has a good bulb, I'd love to hear from him.:yes:

Does the schematic look anything like your set?

John

Some of it looks the same, like the horizontal and vertical circuits. The schematic shows a doubler in the HV section though, where I have only a 1B3 and a damper. I should be able to use it to figure out what's going on with the horizontal not locking, which is probably gonna end up being something with either the 12AX7 sync seperator, or the 12AU7 right after it. I know AGC is working fine, because if I inject a signal into the tuner I can cut off the 'picture' on the screen by adjusting the AGC pot. It goes blank past a certain point.
I'll have a look at the horizontal circuitry in detail as well on the off chance something's still amiss there, but it seems to be working fine. Well see.

She lives! Turns out the Halolight worked, it just needed a good cleaning. Apparently the bulb is very sensitive to static interference, so I cleaned out the housing it sits in, then shot the bulb and plastic with anti-static spray. Works like a champ!

Only reason why it didn't get a solid picture last time I worked on it was a few out of tolerence caps in the horizontal hold circuit, causing a no-lock situation. Replace the caps, and bingo, great picture!

This is going to end up being my favorite set, I can already tell. With the Philco I just kinda got that 'cool, it's an old TV' feeling. With this set, it's entirely different! The Halolight is something to behold, especially if you've never seen one in person before. It's like there's a whole new dimension to the TV, inviting you in to watch.

Dark is the best time to watch it, obviously. You don't need much light from the Halolight to make a difference, either. I found it gives best picture when the Halolight is set just above the lowest setting. I started a new thread to showcase the pictures, check it out!
http://www.audiokarma.org/forums/sho...d.php?t=242474