View Full Version : Philco C7542BPC (3CY91 chassis) console


RetroHacker
03-30-2016, 02:09 PM
This was a curb rescue, found amongst a sofa, coffee table, and other furniture. The pile marked in the time-honored traditional way, with a piece of corrugated cardboard, scrawled upon with a Sharpie to proclaim everyone's favorite word - "FREE". I stopped to investigate, and couldn't not bring it home with me - you don't see too many early 70's consoles any more, and this one is pretty clean. I managed to pick it up by myself and get it into the back of my van.

This is a Philco/Ford 3CY91 chassis, and is in Sam's 1344-1, dated 1973. I was even able to get the Sam's from my local source. It definitely appears to have been a quality set, with a cold chassis transformer type power supply, and fully modular.

I powered it up, and got a fairly bright, fully scanned static filled raster, although the convergence seemed a little poor. I connected a game console for a quick test pattern, and was able to get it to tune in partially - the horizontal wouldn't lock, and the color would only come in if I pressed harder on the pushbutton. While attempting to adjust the user control for horizontal hold, I lost the vertical deflection, and the breaker popped and shut off the set. Clearly, it's going to need some work.

Still, an interesting find. Would be nice to get this one running again, it's a good example of a modular solid state set.

-Ian

rca2000
03-30-2016, 02:23 PM
THIS is on my "most wanted" list !! I had one in the late -'80's..a 19" set..

it is a cold set with SCR deflection !!

If you do not want it...I DO !! Are you coming to the ETF?

DavGoodlin
03-30-2016, 03:26 PM
That was known as the Philco "boss" chassis. The last gasp of engineering before Philco was sold to GTE in 1974.
They were not as much a trouble-free workhorse as the XL-100 but they made a picture just as good.

Get a full roll of Kester, a hot Weller WP40, magnifying glass the pull the chassis and have a solder-fest.

rca2000
03-30-2016, 04:02 PM
A lot of bad connections I guess?

Kind of an unusual CRT filament ckt..Stby is a normal; tranny...but RUN if off of the FLY. Something like the Moto "JA SMPS "ckt-- that Switching supply powers the tube in RUN...but a small tranny does it in stby..


I STILL wonder...how the "old school techs"...handled the JA power supply...back "in the day" Today--it looks a LOT like a typical chopper SMPS--which is VERY familiar..but when it was in CURRENT production? I would guess it gave a LOT of headaches !!

sampson159
03-30-2016, 11:08 PM
had several of these ss sets and a hybrid as my main set.the hybrid produced the best picture of all the sets i ve owned.it was amazing.sold it after 5 years of use and aquiring a sylvania superset with a 25vdmp22.should have kept the philco

radiotvnut
03-31-2016, 12:29 AM
Solid state Philco-Ford color sets were rare, 25 years ago. In close to 30 years of finding old TV's, I've only seen 3 solid state Philco-Ford color sets. One was a 19" motel set, one was a 19" set for consumer use, and the other was a 25" color TV/stereo combo with a chassis similar to this one. Your set looks like it may have an RCA CRT in it and it looks to have a varactor tuner; which, was high end in the early '70's.

zeno
03-31-2016, 10:45 AM
This is a great find. Very rare chassis, we were the
biggest shop for miles & only saw 6 at the most.
As said start with a roll of solder. They get cold
joints everywhere especially the mother board.
Also known for multiple problems.
Keep us posted & good luck !

73 Zeno:smoke:

DavGoodlin
04-01-2016, 03:15 PM
This looks pretty relevant to an SS Philco http://www.ebay.com/itm/Audel-Servicing-Philco-TV-for-1973-Color-B-W-TV-Repair-Vintage-1976-/281980358077?hash=item41a756cdbd:g:NJUAAOSwhcJWOL3 S

IIRC I saw a 19" version of this chassis when first starting out, it was 4 years old then and had a intermittent PS problem. I probably gave it back without much improvement. I was also unaware of how bad the solder joints could be.
I was baffled by a SMPS supply but I was not yet doing SS TV repairs for an income, then I had to learn...

zeno
04-01-2016, 04:02 PM
I STILL wonder...how the "old school techs"...handled the JA power supply...back "in the day" Today--it looks a LOT like a typical chopper SMPS--which is VERY familiar..but when it was in CURRENT production? I would guess it gave a LOT of headaches !!

Ah yes the JA. First one I saw I didnt get at all. Showed the boss
the Sams & he said " buy a Fing board. I have NO idea how this
works". Had I continued I am sure I would have called Moto
for help. They would say " why dont you buy a Fing board. We
use modules for you ! "
Back then there were just a few killer sets.
1) Sony SG613 sets
2) JA Motos
3) RCA SCR sets
4) how to keep a sears Warwick SS chassis running !
Specialist got the Sony work, dont leave mad just leave !
Motos plugged on, not many anyhows.
RCA SCR sets were reliable & predictable.
Sears Warwick SS "take it to sears" followed by tears from customer.

73 Zeno:smoke: stuck in the past.

rca2000
04-01-2016, 05:08 PM
I STILL would rather work n a JA module set.....than ANY SG_613 or such Sony NIGHTMARE. SMPS supplies are "old hat" to me by now--since EVERY flat-panel set uses them...I see a LOT of them..and usually have GREAT success fixing them. The JA is pretty normal in the SMPS design--other than the fact that is uses an NPN transistor for the Switch-out transistor instead of a MOSFET..as nearly ALL SMPS units do now.. And locking to the horiz. rate for SMPS operation was done in a lot of sets, during the CRT era..

But those Sony SG sets...HATED them.. You would spend a lot of time getting the horiz. ckt repaired..regulator replaced and such..power it up and BOOM !! ALL of it was gone in a quick FLASH. and I do NOT think a variac was of much help...either. And sometimes...they would work...and you would THINK all was well...and then BOOM.

Best thing for the SG sonys''....a packer truck !!

Geoff Bourquin
04-01-2016, 11:29 PM
Hated the SG613 sets
In the late 80s I thought I had the JA panel figured out but they'd fail on me in short order. Looking back, I think it was because I used ECG or SK transistors instead of the original numbers. I knew better than to sub the SG613 with anything. I had the same problem with one model of TMK set in the 90s. The SK transistors would overheat and die, even though the voltage/current ratings were OK. Pretty sure the problem was the substitute replacements were too slow for the switching supply. Probably something like that in the JA too. If I ever see a JA again I'll know better

Jon A.
04-04-2016, 02:02 PM
I have a Sony with the infamous SG613. The cabinet is near mint and it ran when last powered on, so it stays and I may even re-cap it at some point.

Anyway, that's a sweet console. Gotta love the rarities. Now, how about the face test?

truetone36
04-09-2016, 10:44 PM
I used to have a combo set in an upright armoire style cabinet with this same chassis. Philco sets from this era aren't seen often anymore.

Findm-Keepm
04-11-2016, 12:56 PM
While your set uses the "Horizontal Boss" chassis, the vertical Boss used the same modules with little change between the two chassis.

Attached is some info from the Philco Service Notebook, first published in 1975, after your set was built.

Hope it helps,

AUdubon5425
04-14-2016, 02:22 PM
They had a hybrid or ss Philco Ford combo on the CL here last month, priced out of my budget. Had vertical folding doors over the controls.