I've been reading quite a bit about the heat build-up problems within the Predicta. I would like to install a quiet fan for ventilation, but am unsure where and how to mount it. I plan on using a 110v model designed for cooling a home theater rig. Does anyone know the best place to install, how to mount it, where to tap power and the best type of fan to use? Thank you!

http://i523.photobucket.com/albums/w353/chemo64/Predicta/fan.jpg

I just set mine on top of it over the vent holes, over the main chassis (pricess model)

That being said I dont run the set for more than about 1 hour at a time, so I rarely bother with it anymore.

I initially thought about doing something similar, like placing a floor fan behind it. I won't be watching it all that often (and not at all, unless I fix it!) but for the occasional "movie night" with the wife (this plan was crucial to raising the WAF). So I'm figuring after an hour, there will be some considerable heat present. The internal fan idea satisfies my semi-obsesive nature way more than the floor fan solution.

I toyed with the idea of just hanging it on the back cover with some plastic tie wraps. that is the same size fan I use, it will keep it cool.

I have also wondered about leaving the fly cover off to aid in circulation. I dont know how much heat the 1G3 puts out but I figure the fly is the most critical part.

along those line I wonder if anyone has ever tried using another fly that may be easier to find?

I under stand the WAF :yes:

I zip tied one to the rear cover and wired a plug to it. Really helps.

I think I'm going to try mount it horizontally to the upper part of the chassis in front of the HV cage. Since I won't be running it all that often, I won't have to worry about the dust build up in the vent holes. I'll give it some more thought, and take some pictures once I decide and construct.

And yet another question:

I have a Sam's Photofact and a Philco Service Manual, both from 1959. I've discovered they differ in the listed values of some resistors and caps. The Sam's list is identical (as far as I have checked) to what is on the chassis. The Philco manual states that the parts list reflects the optimum values that may differ from original factory parts.

Which should I follow?

And yet another question:

I have a Sam's Photofact and a Philco Service Manual, both from 1959. I've discovered they differ in the listed values of some resistors and caps. The Sam's list is identical (as far as I have checked) to what is on the chassis. The Philco manual states that the parts list reflects the optimum values that may differ from original factory parts.

Which should I follow?

Since you have the Philco manual, and it states that it is updated for the best circuit designs, I would tend to follow it. I've found mistakes in Sam's Photofacts several times.

Since you have both sets of materials, I'd check and compare everything being considered for replacement.

Since you have the Philco manual, and it states that it is updated for the best circuit designs, I would tend to follow it. I've found mistakes in Sam's Photofacts several times.

Since you have both sets of materials, I'd check and compare everything being considered for replacement.

That's sound advise, thank you. And that is exactly what I will do.

Nobody's answered the question as to what type and how to power the fan. If I ever finish up my Barber Pole and put the back on I would use a fan also. At Least with a standard size box fan, wire mesh filters are made to the same size as I would be concerned about blowing dust through, plus on this kind of model I think it would be best to use a slimline model and mount on the bottom of the cabinet, blowing up..only practical way.

As for what you can do, use a standard A/C fan that plugs in seperately. You could go across the on/off switch but I'd hate to stress that switch anymore than needed. Yea, I know a box fan draws little current but I kind of like the idea of it being isolated from the set, besides a hot chassis!

Or use a D/C fan that you can power up with a "Wall Wart"...low current "and" low voltage "and" isolated.

And as mentioned elsewhere, I'd be concerned about the Flyback too. Actually, it may run warmer than that 1B3! And that cover is there for radiation protection and RF Shielding, not that these things radiate Mega-Rhms to begin with but the concern would be "prolonged exposure".

I've run my Predicta for maybe a couple hours at a time and yes, the Flyback gets warm but it seems to maintain it's temperature (and I've been keeping the lid off).

I tried using a fan on my barberpole. The noise drove me nuts, so I got rid of it.

Putting on my contrarian hat, I'm not a big fan of retrofitting old TVs with things they never had. Somehow, zillions of Predictas survived long, hard service in homes and motels. Yeah, some had heat problems, but many did not. If you only watch yours for an hour or two per month, you may have to wait 200 years before seeing a heat-related failure.

If you vist the ETF museum, you'll see TVs more valuable than any Predicta playing for hours on end without cooling fans or special soft-start circuitry.

The type of fan or exact placement doesn't seem that critical. What you want is some air movement, but not a hurricane. Setting any sort of little fan anywhere behind the TV may work as well as anything.

Forcing thousands of cubic feet of air through a chassis also brings in dirt. Think of the computer chassis you have seen, where every square inch of the interior is clogged solid with dust and hair, which then causes acute overheating. That ginormous dust bunny didn't grow legs and walk in. It was created by the fan, one particle at a time.

Just my $0.02.

Phil Nelson

Something to consider is the multi-speed 5" and 7" fans used in desktop computers. They don't make much noise on the lower settings and will get juuuust enough air moving.

As a side note, Apple considered putting a fan in the Apple IIc when they designed it because of the compact design. They found the floppy drive created some wierd convection currents that made the computer run cooler oddly enough.

I've decided to mount the fan in the inside-right of the cabinet next to the tuner and HV cage. It will pull the air mostly from the back and bottom, and give good ventilation the fly. I'll tap directly into the 110v feed at the P.T. and hook it to an independant switch I'll mount from the back on the bracket surrounding the P.T.
That way, I can turn it on of we're watching a longer movie, and not when I'm just showing it off or watching an episode of Dobie Gillis.