Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early B&W and Projection TV

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 03-30-2018, 12:01 AM
Thyratron Thyratron is offline
VideoKarma Member
 
Join Date: Mar 2007
Posts: 92
11L43 "motel" Predicta: advice needed

Hi everyone, it's been a long time since I've been on here; it's nice to see that some of the old names are still around! I picked up an 11L43 Predicta ('61 date codes), in unknown working condition (though it had been powered up recently). Getting it home and opening it up, I was expecting the worst, but was greatly surprised to find a clean chassis with only some surface dust (not the caked on mess you sometimes see), and some orange drops and other newer looking caps with nicely trimmed/routed leads and clean, professional soldering. I didn't pull the chassis, but that was what I could see from the top. Given that it had been already powered up, I decided to carefully do so myself just to see what I had to work with. To my amazement, upon control adjustment I was greeted with a clear, centered, beautiful picture and excellent sound. I actually watched it for about three hours without any kind of fault, other than a slightly shrinking vertical after the set was on for a while that the height/v-lin controls couldn't adjust completely (they were maxed and there were still small gaps at the top and bottom). In all, it was really unexpected, and since then I've been using it quite often with similar great results.

So my question is this: given how well the set seems to operate, am I better off leaving well enough alone? I had figured that the full servicing would be necessary, but the set was apparently owned at one point by a radio/TV hobbyist, so I was told; I would assume that he must have done some work on it, although how extensive it was I can't say. I'd like to fix the vertical issue (any suggestions on that?), but otherwise it seems to operate so beautifully that maybe going into it might be a case of "fixing" something that doesn't need it. I should admit that I'm not an experienced TV restorer by any means, and don't have specialized test equipment, so anything beyond basic repairs would probably have to be sent out to a shop (yet to be found). Any advice is welcome.
Reply With Quote
  #2  
Old 03-30-2018, 12:12 PM
bandersen's Avatar
bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
Posts: 8,085
It's impossible to say. We don't know what was done to it or what components were used. I wouldn't advise leaving it unattended while it was running.
__________________
Here are my Vintage Radio & TV YouTube Channel and Photo Gallery
Reply With Quote
  #3  
Old 04-09-2018, 03:59 PM
Thyratron Thyratron is offline
VideoKarma Member
 
Join Date: Mar 2007
Posts: 92
It's doing great so far. (I'm always mindful when operating any of my vintage equipment, even the fully restored items). It's been well maintained, to be sure, although I will bring it in for a tune-up and a general check over in the coming weeks.

Meanwhile, there are a few things I'd like to take care of. First, is the dial lamp accessible from the front of the unit, maybe behind the concentric tuner knobs? It looks like the tuner blocks access from the back, without removing the chassis, so I just wanted to see if there was an easy way to get at it. And what type of lamp does it take?

Secondly, I'm thinking I'd like to remove the CRT cover to polish it properly, as it has some surface scratches. Is this advisable? I've read the steps on how to do it, but I can just envision that gold-colored outer band breaking when trying to reinstall it. Would I be better off just polishing it in place? (Wet sanding isn't necessary; I think Novus or the like will take care of it).

And finally, what are your thoughts on using a fan over the chassis when operating the set? I use one on the power tubes of my audio receiver (simply for longer tube life) and it seems to reduce the heat buildup greatly--but that's an open backed cabinet. I'm thinking that putting one behind the TV set will just circulate the heat back over the chassis, which might not be desirable. It actually seems to run in a fairly cool manner (for a set of the era), but I'd just like to prolong the circuit board and tube life as much as reasonably possible. I wonder if a small fan mounted on the masonite back (pulling outward rather than blowing inward) might be the way to go. Any thoughts on this?
Reply With Quote
  #4  
Old 04-09-2018, 08:10 PM
madlabs madlabs is offline
VideoKarma Member
 
Join Date: Jul 2016
Posts: 388
I took mine off to polish, it was easy. The band is pretty flexible. I took the back off of my set to allow better air flow and it greatly decreased the heat. I'm sure a fan would be better but I wouldn't want to hear the noise. Maybe a real quiet fan or a muffin fan run at 1/2 voltage.
Reply With Quote
  #5  
Old 04-10-2018, 04:07 AM
decojoe67's Avatar
decojoe67 decojoe67 is offline
VideoKarma Member
 
Join Date: Apr 2011
Location: Long Island, NY
Posts: 1,322
The only set I use a fan on the chassis with is my '48 Halicrafters 505. The set is known to go dark when the flyback heats-up, so in that case it really helped with one mounted right over the open HV box. I have also attempted to run a small fan in the back of other vintage TV sets when I use them, but if you're only going to use the set sparingly, I, and other repairman I've spoken to, do not think it's really necessary. As said previously, the noise, even with a smaller computer fan, can be rather annoying.

Last edited by decojoe67; 04-10-2018 at 06:02 AM.
Reply With Quote
Audiokarma
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:23 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.