Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Rectangular Screen Tube Televisions

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 05-21-2017, 02:47 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Sooo. a Hallicrafters 815 followed me home...

Argh... the sickness... it's getting worse :P
(Since I've last been around here I sadly had to sell my Fleetwood console TV; it was simply too large and bulky to take with me ... I guess this is an attempt to fill the hole in my heart? )

This followed me home for a song and a taxi ride (because there was no way I was gonna carry that to and from relevant public transit) No power cord, which means nobody's plugged it in to try it out. Cabinet is pretty beat up, but inside looks to be in pretty good shape and had an easy life. All the tubes are there, no melted flyback or scorch marks on the underside of the chassis, and no critters have made it a home. Minor chassis corrosion, and I don't see any signs of large-scale butchery on the circuitry.

Step 1... Get some service info. Any leads? Looks to be a Hallicrafters 815-A5. Quick google points to a SAMs and not much else, but I will admit it was cursory and not in depth yet.

Initial pictures - note the revision stamps on the tube chart where they've opted to make the whole set a 6v one...




Reply With Quote
  #2  
Old 05-21-2017, 04:17 PM
Olorin67 Olorin67 is offline
VideoKarma Member
 
Join Date: Feb 2014
Location: Milwaukee
Posts: 927
looks like the set I had, i sold it a couple years ago to someone from Chicago. i got it for free about 1989 at an estate sale.
Reply With Quote
  #3  
Old 05-21-2017, 05:52 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Looks like the service info is either Riders 7-1 or Sams 124-6. Anyone have a scan or will I have to cough up some cash?
Reply With Quote
  #4  
Old 05-21-2017, 08:07 PM
EdKozk2 EdKozk2 is offline
Tinker
 
Join Date: Mar 2014
Location: Elkhorn, WI
Posts: 542
I looked up your set in Sam's 124-6. The Sams schematic shows a 16GP4 round crt. What's in your set? There seem to be a few production changes too.
Reply With Quote
  #5  
Old 05-21-2017, 08:24 PM
EdKozk2 EdKozk2 is offline
Tinker
 
Join Date: Mar 2014
Location: Elkhorn, WI
Posts: 542
Did some more checking, the Riders' 7-1 schematic shows a 16RP4 crt for the 815. Looks like Sams tried to cover eight chassis in one schematic. Some had an AM radio in a console version.
Reply With Quote
Audiokarma
  #6  
Old 05-21-2017, 08:40 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Thanks for checking, mine's got a 16RP4

Probably a common chassis, there's provision for a phono input in this even though it's a tabletop doghouse (including populated and labeled front switch, not just a "hidden" thing that got left in)
Reply With Quote
  #7  
Old 05-21-2017, 08:50 PM
EdKozk2 EdKozk2 is offline
Tinker
 
Join Date: Mar 2014
Location: Elkhorn, WI
Posts: 542
I'm unable to make you a digital copy from my Rider's disk, copy protected for some reason.
Reply With Quote
  #8  
Old 05-21-2017, 09:01 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Darn, appreciate you trying. Seems my local library has in-house Sams and Riders (hopefully the right volumes). If no luck here I can go take a look and spend some time on a photocopier if they have the right ones.

Is the Sams also a no-go? Even if not identical I'm curious whether it has additional info not in the Riders.
Reply With Quote
  #9  
Old 05-22-2017, 08:23 AM
user181 user181 is offline
VideoKarma Member
 
Join Date: Nov 2013
Posts: 451
Here's the SAMS available for purchase:

https://www.samswebsite.com/en/photo...index/id/66461
Reply With Quote
  #10  
Old 05-22-2017, 05:45 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Given the above info that it might not be for the right set/revision, I'm sure as heck not dropping $15 on a SAMS.

Library did not pan out, only had SAMS up till volume 91, Riders was supposedly there but not on the shelf. They're gonna go hunting for it.
Reply With Quote
Audiokarma
  #11  
Old 05-25-2017, 08:26 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
Looks like the flyback's been replaced. Cap lead to the HV rectifier was disconnected and some anti-arcing bodgery inside the HV cage. Probably arcing because there's a bad pointy solder joint on the clamp.

Lead is too short to reconnect, so perhaps the doorknob cap has also been replaced. Interesting, since the CRT also has a coating. Didn't think doorknobs + dags were common together but it could be because there are several revisions of this chassis, and the earlier ones were roundies.

Still getting my thoughts organized, replacing the caps I have on hand and figuring out what I need to order. I've obtained a SAMS and the Beitman's schematic, and hopefully will have the Riders soon too. More pictures coming this weekend!
Reply With Quote
  #12  
Old 05-25-2017, 11:53 PM
old_coot88 old_coot88 is offline
VideoKarma Member
 
Join Date: Sep 2009
Posts: 2,541
Doorknobs and Dags. Sounds like something outa Edgar Allen Poe.
Reply With Quote
  #13  
Old 05-26-2017, 06:25 AM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
...When suddenly there came a zapping, of corona gently snapping, snapping within my HV cage door...
Reply With Quote
  #14  
Old 05-27-2017, 04:31 PM
VintagePC's Avatar
VintagePC VintagePC is offline
Tube bug got me 05/2010
 
Join Date: May 2010
Posts: 535
A'right, some progress. Spent the day familiarizing myself with the set and figuring out what capacitors I'll need to order.

Started by taking a look at the focus control... it made nasty crunching noises when turned, and on opening, my suspicions were confirmed - it's burned up, as is common with some designs.



How likely am I to find an exact replacement? This is a dual-control with brightness. Rear control is 50K 1/2 watt, focus part (front) is 2500 ohms, 2 watt. Clarostat 25B889. Can always mount focus somewhere else on the rear of the chassis, but would be nice to retain it by the front knob where labelled.


There are also two sand resistors... as is the case with most, the leads are corroded and this one (while it still measured OK) fell apart when I looked at it funny. I didn't have the required value for the other one on hand, I'll have to order it.



Whoever replaced the flyback did some bodgery, and there was a half-baked attempt at squelching some arcs with electrical tape on the inside of the HV cage... Likely because the rectifier cap lead had a terrible solder joint with pointy stray wires everywhere. After unsoldering, there was enough folded/bunched up wire to make it long enough to reach again.... Nice clean and smooth joint now, and also added some heatshrink for good measure since the insulation on the lead was too short.

No, I didn't solder while it was connected to the rectifier... You can see the allen key I clamped to the chassis to hold the HV lead ring while soldering.

More flyback bodgery. Looks like somebody miscalculated wire length; those aren't original wires, so I'll clean that up at some point.


Another interesting thing... these piggy-backed fuses:

I could see this if a homeowner was too lazy to unsolder a fuse and just put a new good one in parallel... but both of these fuses measure good. Any idea why this might have been done?

Another interesting thing is that the doorknob cap under the rectifier isn't really connected to anything... it's bolted to the corona guard ring/mount for the HV rectifier, but that is isolated and just floats. Huh?

I'll also have to take a look at the flyback mounting... the transformer is kinda squished in in an odd position and the replacer bent the cage when replacing it to make it fit. Looks like it might be possible to neaten up if I reorganize the inside of the HV cage a little bit...


Last edited by VintagePC; 05-27-2017 at 04:41 PM.
Reply With Quote
  #15  
Old 05-28-2017, 12:42 PM
Notimetolooz's Avatar
Notimetolooz Notimetolooz is offline
VideoKarma Member
 
Join Date: Mar 2014
Location: Dallas, TX
Posts: 547
Maybe the previous person only had fuse values half as large as called for.
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 10:17 AM.



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