Silvertone 7140
 

Here's a Silvertone roundie I saved recently. Gotta be a rare one, I've never heard of it before. Chassis seems CTC-4ish to me, with the giant hockey puck doorknob cap and HV shorting plug. All original Silvertone brand tubes which test good, so it can't have had a lot of hours on it. Cabinet is beat to hell and back, gonna be another veneer job just like the CTC-7 Ed now owns. That means this one has to wait for at least a year while I catch up on house payments, all my money goes there till further notice. Unless of course someone has a 15GP22 to sell... :D

http://miniman82.4t.com/images/Silvertone/front.JPG
http://miniman82.4t.com/images/Silvertone/chassis1.JPG
http://miniman82.4t.com/images/Silvertone/chassis2.JPG
http://miniman82.4t.com/images/Silvertone/chassis3.JPG
http://miniman82.4t.com/images/Silvertone/chassis4.JPG

Here's the Sams on it, Steve was nice enough to put it up on the ETF site.

http://earlytelevision.org/pdf/Silve...sams-388-1.pdf

Reminds me a lot of a 19CT1 with that bezel.

That is one cool set. The metal shield over the front of the yoke, Looks like the ctc5 yoke. Is there a ground wire attached to it? What are you going to do with the grill cloth?

528 is Warwick ?

jr

Yep, 528 is Warwick.

Is it missing an HV cage or did they just have all those tubes and the flyback out in the open?

How's the CRT?
That looks like a unique mount / insulator boot / edge magnet setup.

Very nice find!

Wow, what an unusual design. Definately not a direct clone of a CTC-4. I wonder if any more examples of that chassis still exist.

Yes, it uses a different color demodulation method, for one. Not to mention the different physical layout. And what's with that vertical centering control -- a dual pot with a 500-mfd non-polarized electrolytic. This set should make a very interesting restoration story.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

It's missing, we searched the whole house looking for it but no luck. It's just a perforated steel box that covers the fly and horizontal related tubes, you can see it clearly in the full Sams. I only scanned the schematic info for ETF to upload, my computer can't handle large files for some reason. Probably time for an upgrade.



Wayne, the CRT tests very good but the base has seen better days. Probably going to have to load it up with sensor safe sillycone to shore it up, I'm too nervous to attempt surgury on a good AXP. The insulators around the tube are actually pretty close to what the Admiral Ambassador has, and I swear Anchor Co. had a monopoly on HV insulators back in the day- they made every single boot for every AXP set I have! lol

This is the only one known according to ETF, but that doesn't mean there aren't more out there. Never seen a color set this early with the chassis around the tube like this, but seen it a lot with B&W stuff. It's about the same size/weight as the Admiral Ambassador that came from Canada, just with the circuits around the CRT instead of on a flat chassis.


Right, I guess I just meant that it has the same doorknob and HV shorting plug so it has to have some borrowed parts at least.

The 1954-55 Motorola color sets had a vertical color chassis, but not really around the CRT.

http://www.earlytelevision.org/motorola_19ck2.html

Very interesting indeed! No PC boards either.
This will be fun to follow when you post the play by play.

The circuit is very similar to the licensee circuit Hoffman used. Should be a pretty decent performer when it's all buttoned up! Very nice set :)

Totes jelly! (totally jealous) I love Sears for this kind of bizarre old and new engineering mix. I collect their radios and a typical thing is a modern front end with octal tubes mated to a bank of completely outdated tubes like type 45s in a late 30s set. I just love the wrapped chassis- it must also make the set much more balanced. My CTC-4 Seville is hideously unbalanced- heavy in front and chassis-side of course.

John H.

Very happy for you ! I have a Sears B&W set I got a few weeks ago, 17" tube
based portable, and all the tunes are original also. Also a Wells ID numbered
tv. My set is like two our family had when I was a kid. We also had never had
to replace any of the tubes..... Maybe WG designed sets more under the tubes
max current - and they lived a lot longer..... For this set just look at the
H and V outputs..... from the pdf posted...... I'm getting more respect for
WG when I look at the insides of my set, and this color set.

Looking forward to seeing this one come back to life.....

Nice find, hope there are more out there.....

I wish there were more out there about the companies design criteria, and
in this case about the circuit design, if it was licensed from someone else,
etc.....

.

The set shown is a Warwick product, Sears source # 528.
Wells Gardner was never interested in building products for Sears. Most firms claimed that the Sears buyers were too cut-throat and there was little room for a decent profit margin. Sears had an interest in Warwick from the mid-50's.

I know, Sears was as bad as Walmart from what I have read ! But unwritten
is ~ Did Sears expect Wells to stand behind the design as far as excessive
warranty work on all their sets....? Did Wells have to carefully balance their
profit with whatever Sears may have tried to stick them with if the set
were to have a chronic problem leading from a design goof....?

I think it was 60 minutes that did a story on Rubbermaid and their dealings
with Walmart when they got into WM. Sounded to me like Sears buying up
companies they starved while working on exclusive deals.....

OOPS I think I got my Wells, and Warwick mixed up.... At any rate, read as
"The company Sears Sourced for the tv..." Sorry....

.

Instead Wells Gardner built a huge amount of sets for Montgomery Wards- all the "62" preface sets.

John H.

Didn't know warwick would even be capable of its own color set this early. Also it seems by '58 no one would even use the 21ax anymore. Wasn't the 21cy introduced by then?

Maybe Warwick got a deal on a truckload of obsolete 21ax's. It's a very interesting chassis layout. I'm really not too crazy about the styling of the cabinet, but it'd still fun to have such a rare set. Looking forward to seeing this one restored.

Yes... according to Keller " The Cathode Ray Tube" page 180, 1957 was the first year for the 21CYP22... I am surprised to see a 21AXP22 in a 1958 set... perhaps Warwick got a deal on remaining AXPs? :scratch2:

jr

Either that or they just wanted to use up possible remaining stocks.

I think it was no different on the commercial end as the retail end..... While new tv's
came out that were all solid state, you could get a few year old tube design for
$10. - $20. less....

I'm sure they were still cranking out 21AX's somewhere....

What ya got for a date code on that tube miniman82 ????

.

The SAMS folder for this Silvertone is dated Feb. 1958. SAMS was always published months after the release date of the TV it depicted. The Silvertone was produced some time earlier in 1957. No reason to believe there was a shortage of available 21AX tubes in 1957. Wondering if this set showed up in the Christmas 1957 Sears Catalog?

-Steve D.

No idea, the base is mangled. The pins are all there, but the chunk that should have the date on it is missing.

An excellent and rare find/save, in my opinion, congratulations, miniman82! I especially love to see pictures of sets that I have never seen, much less even knew existed, and this is certainly one of those, for me!

That is one awesome set!

Finally mostly nearly almost done unpacking the TV related stuff, that means it's time for an update! :D


Got some time this weekend to pull the chassis back out of the cabinet (no CRT's died in the back of the U-Haul truck on the way here thank GOD!), so I put it on the bench and brought it up with the variac. First I removed the horizontal and vertical deflection tubes, so I could reform the power supply caps. That went well and nothing got hot, so next I scoped the horizontal oscillator to make sure a waveform was there to drive the HO tube (it was), so I put all the tubes back in and brought it up...


Nothing.

It was absolutely dead.

Started digging, and there's voltage to the vertical oscillator. Strange it should be running, wonder if there's bad caps in it. Twiddled the LIN and height controls because sometimes after sitting there's high resistance in the elements that can keep it from working and with a BANG and a SNAP, the vertical oscillator started running. This was a smokers set unfortunately and it's very dirty and dusty, yet another chassis I'll end up pulling all the pots out of for a scrab and deoxit. Dammit. Well for now I had vertical sweep, which on this set is powered by B+ not boost, so I moved on.

Still no horizontal, though I can hear it sort of trying to spool up- at least when the dirty HO tube's socket doesn't decide to not power the filaments. Note to self, schedule socket cleaning...grrr...

Looked at the HV wiring on the 3B2 and 1X2 focus rectifier, and it's toasty. All cracked and mangled. Possibly horizontal is getting dragged down by HV leakage? Took me 3 hours to get the HV cup apart on this because like a CTC-4, there's a giant doorknob built into the bottom of it. The tin can lid of it has to come off the bottom first, and it was soldered together. Took a torch to get that apart. Finally get to the guts of it only to discover that the rectifier socket had been replaced with a ceramic one at some point in its history, and it's way too big for the little metal plate it's mounted to. Now it's all deformed, and I gotta pound it back into shape.

Get the old socket removed and the pie plate straightened out, but I don't have any octal sockets that fit in the smaller than normal hole. Piss, this just ain't my day. Thankfully I had won an Ebay auction for a replacement one not long ago, so I stuck that in with some new Belden 40kv anode wire. Let's try this again: only 5kv...

OK, not good. Either the flyback is bad, or I got some kinda serious unknown drain on HV somewhere. I already knew the CRT tested good from when I picked it up, so I knew that wasn't the problem.

Oh BTW, I discovered at some point that the selenium LV rectifiers were past their prime, so B+ was seriously sagging as soon as the tubes started drawing current from the power supply. Those got replaced with silicon along with some new electrolytic caps, I'll add series resistance to it later.

Only other thing that can drag down HV is the shunt tube, a 6BK4. So I disconnected the CRT anode lead and the plate cap of the 6BK4 and try one more time before assuming the worst- Bingo, 29kv shows up on my meter! OK cool the 6BK4 grid is probably too high, so I put a meter on it. Sure enough, it's at 210 when it should be around 135 VDC. HV pot doesn't do anything either, so I trace it out.

The 6BK4's grid receives its marching orders from a HV bleeder string that starts on the focus rectifier, goes through some very high megohm resistors, then the HV pot gets a chance to shunt some of that voltage to ground, then there's a 1-meg to the 6BK4 grid. So logically if the pot does nothing and the tube is stuck fully on, there's gotta be an open somewhere either on the pot or the 1-meg going to the grid. Read through the pot and it actually came back nice and smooth with the correct resistance, so I look at the 1-meg going to the grid- it's drifted up to 14 meg! :sigh:

After replacing the 1-meg grid resistor on the 6BK4 I now had a full bright raster with controllable HV, so I set the pot to around 23kv and called it good. Now all the major parts have been verified as working, so I can sit down after the ETF meet and start ordering all the caps this thing is going to need to be reliable.

Also need to build a new HV cage for it, we searched the house it was in but didn't locate it.

That being the case, I pulled the CRT and took a shot of the backside of the chassis. CRT is a Sylvania made tube according to the EIA code (if that's what the 312 on the label is anyway), and has the original Silvertone brand label on the bell. First color set I've ever owned to still have all of it's original tubes in it, gotta be some kinda miracle. Enjoy the pics. :thmbsp:

http://miniman82.4t.com/images/Silvertone/chassis5.JPG

Here's a link to a high-res shot of the chassis: http://miniman82.4t.com/images/Silvertone/image1.JPG

The CRT:

http://miniman82.4t.com/images/Silvertone/CRT.JPG

Congrats on getting it going Nick. The chassis reminds me a lot of MOTO chassis, a gobbldygook hodgepodge nightmare. Not nice and orderly like a RCA. God knows why they work at all, but they do.

that is a awesome set, look's all original to .

According to the code-date stamp on the label, the CRT is from 1960. Sears Silvertone replacement CRT's were always sourced by Sylvania.
The original CRT was probably an RCA.
The original owner might've had a maintenance agreement from Sears. That would explain all the Silvertone branded tubes. :scratch2:

Thanks Bob, it is a mess isn't it? lol

Dave, I assume you're looking at the numbers '016' on the label? I guess that means 16th week of 1960, so it probably is a replacement. What makes you think the original was an RCA? The other Sears set I got from the same house is just like this one, all original and untouched (CRT replacement aside). The owner was very proud of his Sears brand items, and probably had service agreements on all of it.

Next task will be carefully replacing the CRT base with a new one, don't suppose anyone has a spare Silvetone base for me? That's gotta be a rare item, if it even exists. Probably just put a generic one on there, anyone got one with no markings that could be donated to the cause? I'll look for a brightener at the museum, but don't know if they have one.

Ya know, well this might not be available in your case but with 3D printers and laser scanners, it's possible to replicate things like bases and other parts for these TV's.

Wouldn't it be neat to download a file with the 3D information for, say a knob that you're missing, then pay a few bucks for a 3D printer to make one?

I do have a Silvertone base I saved from a junk tube, however it's a 1961 date code and has an RCA 274 EIA code.
It's yours if you want it.

Man, vk comes through again! I'll take it, how much you need to change vet shipping and whatnot to 20634?

Thanks Eric!

P.M. sent.

Thanks Eric, I love this place!

It seems, RCA made all the 21AX CRT's. Sylvania might've just regunned them or if it was a new tube, Sylvania bought it from RCA and relabeled it.