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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Wed 12, 2020 6:34 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1704
Location: Phoenix, Arizona
To get closer to a Hugo Holden restoration I need to replace the electrolytics in my set.

There are two mullti-section electrolytics in the set

30/30/20 @350 volt can

30/30 @150 volt two section tubular (mounted under the chassis in a clip.

I see that a company called CE Distributing makes the Twist-Loc can electrolytics. They are mostly making replacements for audio and guitar amps. They claim to use original Mallory machinery.

I am wondering if any of you have tried their caps as opossed to re-stuffing. They have values that are quite close to the original can in this set.

I may have already put a small 20 @350 directly in for the video amp which leaves the two 30's for the 250 volt supply.

Thou shalt not modifiy

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Thu 13, 2020 12:12 am 
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Posts: 731
Jim,

I have used these capacitors. I'm pretty sure they are the ones sold by Antique Electronic Supplies AES, https://www.tubesandmore.com.

They appear very good and I have not had any issues the the ones I have used. I prefer these to re-stuffing the twist lock type.

If you look on this thread about magic eyes, you will see I posted a picture of some Seeburg Juke box amps, those capacitors there are the new manufacture ones from AES, no trouble with them over about 5 years so far:

viewtopic.php?f=19&t=372006

So as far as electrolytic caps go, they are as good, if not better than the originals.

I also used the small sized twist locks in the restoration of my Meissner 1939 kitset TV, no issues with those either, also from AES.

Hugo.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Thu 13, 2020 1:08 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1704
Location: Phoenix, Arizona
I did email the manufacture and they did refer me to Antique Electronic Supply which is here in Tempe AZ where I live.

They don't do custom work unless you order 50, and I only need one.

They are also not cheap.

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Thu 13, 2020 5:11 pm 
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Location: WI 54812
I seem to recall that those CE caps are nothing more than modern caps inside the Mallory style cans. So essentially they're re-stuffing new cans. Practically speaking it would not make good sense to use the original internal construction methods.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Thu 13, 2020 7:07 pm 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Phoenix, Arizona
As stunning as Hugo Holdens restorations are, I go for more of a repair job myself. I'm certainly not knocking Hugo, I am just too lazy to go to the trouble.

I have not restuffed electorlytics or tubulars myself. I do remove old solder and extra wires from solder lugs and orient outside foil and put the cap in the same position if possible.

Part of the problem with can electrolytics is if the tabs are soldered directly to the chassis they are hard to get out intact without the tabs breaking at the twist. As I recall from the last time I cut a can apart it was stuffed in there fairly tight.

This said, I have heard that some of the re-stuffs have failed prematurally. Some of my radios and TV's still have the original capacitors in place.

In the case of the admiral 19A1 I put a couple of oddball tubulars under the chassis for the B+ filters 30 @ 350. I believe I put some other axial lead electrolytics various convieniant places for the audio output / voltage regulator 30 / 150. I believe the 20 / 350 which is in the can but for video amp filtering. Seems like a bad place for a video capacitor and should probably have a ceramic across it for high frequency.

I have been watching my set for morning news for the past weeks, I need to pull the chassis one more time and evaluate the capacitor questions (there may still be a couple of papers still in).

I want to put the retainer clips back in for the plastic safety window after I evaluate the foam rubber surround.

I occasionally hear a faint crackle in the audio (capacitors maybe?). I have a TV set that used the center ground lug in the 7 pin sockets. Most have a peice of wire from the lug to a lug on the chassis. They also get ground through the mounting rivet. I had one socket in the audio of a Teletone that was only grounded through the rivet and it was a challange to discover it to be the source of noise.

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Thu 13, 2020 7:38 pm 
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Location: Pewaukee, WI
I tend to prefer to leave some patina in my work, and not fix what isn't broken.

If a set is 40, 60, 80 even 100 years old and it looks like it I can't fault it for being true to what it is.

It took decades for my sets to look as they do and if they are not excessively shabby for their age I'd rather leave what I can original.

I can appreciate making it as good or better than new (it can be truely breath taking) but at some point it is almost easier to build a new one from scratch (which would also be pretty cool to see).


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 2:27 am 
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I have had good luck with the CE can caps, though they are indeed a bit pricey. There's a series of videos on YouTube showing how they are made using the old Mallory equipment - very interesting to watch (they are not just modern caps stuffed in the cans).

Here's a link to the first episode:
https://www.youtube.com/watch?v=yfSSIO2c_ak


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 3:16 am 
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studioguy wrote:
I have had good luck with the CE can caps, though they are indeed a bit pricey. There's a series of videos on YouTube showing how they are made using the old Mallory equipment - very interesting to watch (they are not just modern caps stuffed in the cans).

Here's a link to the first episode:
https://www.youtube.com/watch?v=yfSSIO2c_ak


My apologies and I stand corrected. I could have sworn there were old threads around here with reports of folks opening these and finding modern caps inside. Possibly wishful thinking on my part. Thanks for posting the video's as proof otherwise. Very fascinating and educational to see how these were manufactured. 8) With that said I do stand by my other previous statement.
Kevin Kuehn wrote:
Practically speaking it would not make good sense to use the original internal construction methods.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 10:16 am 
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studioguy wrote:
I have had good luck with the CE can caps, though they are indeed a bit pricey. There's a series of videos on YouTube showing how they are made using the old Mallory equipment - very interesting to watch (they are not just modern caps stuffed in the cans).

Here's a link to the first episode:
https://www.youtube.com/watch?v=yfSSIO2c_ak


It is good that someone like yourself doesn't jump to conclusions and make derogatory remarks about a component that they have not subjected to any study and takes the time to find out what the real story is, well done !


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 10:19 am 
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jimmc wrote:
I occasionally hear a faint crackle in the audio (capacitors maybe?). I have a TV set that used the center ground lug in the 7 pin sockets. Most have a peice of wire from the lug to a lug on the chassis. They also get ground through the mounting rivet. I had one socket in the audio of a Teletone that was only grounded through the rivet and it was a challange to discover it to be the source of noise.

Jim


Most of the time these sorts of noises are from carbon composition resistors with a DC current through them, especially in the audio stages. In my restorations, I replace most resistors with 2W metal film types that are about the same size as the originals, but, deathly silent in the noise department.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 10:29 am 
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Electronic Memory wrote:
I tend to prefer to leave some patina in my work...... but at some point it is almost easier to build a new one from scratch (which would also be pretty cool to see).



I doubt it. Have a go at making the metalwork, cutting, folding, spot welding and punching the holes with the precision they did at the factory where the TV or radio chassis and the other metalwork was made. And what about the lost art of CRT manufacture.

They exist in the form they do because of the manufacturing processes that made them, that is not easy to do, suggesting you could make one from scratch. I certainly can't do it.

But I do believe in preserving what is there, so I I have taken to the time and trouble & effort to do it, it will make the work last as long as possible. The word patina to me translates to untreated corrosion.

In my view "restoration" if it has true value at all is "preservation". After all, we are only the custodians of this vintage apparatus , in the end it will be passed on. And one thing I have noticed; human beings treat beautiful and elegant objects with respect. If things look like junk (and don't work either) they tend to be put out in the trash. So my theory is, the way I do my restorations and the time passes, most likely the apparatus will survive.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 4:42 pm 
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Location: Phoenix, Arizona
Understand I appreciate Hugo Holden's restorations and the story that follows. I have the 621TS in the binder I keep when I do a restoration.

I just watched the video link on how CE is making the Can Electrolytic Capacitors using antique Mallory equipment.

I was beyond amazed. Most of the TV's and radios I play with have their old can capacitors on place and still workng. Notice CE applies voltage slowly to form the capacitor, which is why we bring old stuff up slowly on the variac.

I plan to place an order soon.

I am not opposed to the restuff concept, I had seen the Can's in the AES email I get often and just had not taken the time to look through the list of what they make. I am assuming there are types that are close enough to original values in an old TV.

Jim

I bought a big box of old-stock capacitors from a defunct local electronics parts dealer which contained the tubuler type with several wires poking out but most of these check open so I hope I didn't toss them all. The dealer went along their shelves and dumped the various capacitors into the big box, which I bought for 5 bucks.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Fri 14, 2020 8:05 pm 
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jimmc wrote:

I just watched the video link on how CE is making the Can Electrolytic Capacitors using antique Mallory equipment.

I was beyond amazed. Most of the TV's and radios I play with have their old can capacitors on place and still workng. Notice CE applies voltage slowly to form the capacitor, which is why we bring old stuff up slowly on the variac.


What amazes me is that they chose to manufacture a truly vintage style component. Not only in physical appearance and function, but right down to the exact original construction(including Kraft paper dielectric). I'm OK with anyone that respects that kind of authentic construction, however I do take issue with some folks' inconsistency in preservation techniques, in regards to the components and techniques they choose. Mind you it's not a big issue, just a little pet peeve of mine. :)


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Sun 16, 2020 5:30 pm 
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Location: Phoenix, Arizona
This is a picture of 19A11 TV receiving an off air signal of an electronically generated test pattern in real NTSC format with real legal sync being transmitted by way of a properly tuned NTSC transmitter of modern vintage on a high-band VHF TV channel.

The transmitter generates legal vestigial side band.

The defects I see are what appears to be key stoning to the right but this must be due to my camera angle. The circle appears round. The picture is slightly fuzzy due to the plastic safety window (best on I have).

The second picture is the RCA 621TS 7" set. Greyscale (gamma) looks better, picture is brighter, geometry is not quite as good.

The third set is a Scott 6T11 projection (in need of some service).

Jim


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621ts .jpg
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6T11.jpg
6T11.jpg [ 114.23 KiB | Viewed 1778 times ]


Last edited by jimmc on Feb Sun 16, 2020 6:32 pm, edited 4 times in total.
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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Sun 16, 2020 5:53 pm 
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What I notice on the Admiral is a slight horizontal non linearity, but nothing so bad it would be real objectionable with normal programming material.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Sun 16, 2020 9:51 pm 
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Location: Phoenix, Arizona
Kevin

I agree, (Hugo Holden would not allow this :).

As the circuit is running on stored energy in the output transformer and capacitors it must start running out on the right side. Once it has scanned to the right side the Horizontal tube switches on which allows B+ to recharge the circuit for 9 Microseconds. This re-traces the beam to the left side of the screen. Then for the next 63 Microseconds the energy stored in the transformer and capacitors sweep it to the far right side of the screen, 15750 times per frame of video.

I put ceramic .001 capacitors to couple the horizontal to the deflection plates of the tube. Many folks have had trouble with ceramic capacitors in the circuit.

I would be interesting to see how a Motorola VT-71 performs as it uses a similar Horizontal output circuit.

When I punch up a crosshatch it is more apparent the last inch of the right side starts to get nonlinear, although you would likely never notice with active video.

Now that I am motivated to get this set working perfect, I plan to order up some proper parts (Including a new Can Electrolytic). Also all of the resistors in the set are factory original so the high Meg-ohm values should get replaced.

Will it all be worth it after I hit the afterlife and they can,t sell this stuff at the yard sale because nobody can generate an NTSC signal.

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Feb Mon 17, 2020 12:23 am 
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jimmc wrote:
Will it all be worth it after I hit the afterlife and they can,t sell this stuff at the yard sale because nobody can generate an NTSC signal.
Jim


That thought absolutely is a motivation limiter for many of us. The current trend seems to be that most interested in this vintage television hobby are particularly inclined to do their own restoration work. We're mostly creative individuals and these obsolete pieces of technology are like a painting canvas to us. Personally I justify my own enjoyment well realizing that I may be the last one to see the piece operational, all in the name of relatively cheap and educational entertainment. To think otherwise would require a huge leap of faith on my behalf. But it's also heartwarming to imagine they will fall into someones appreciative hands after we're gone.


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Mar Sun 15, 2020 11:44 pm 
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Location: Phoenix, Arizona
For the past couple of weeks I have been watching my little Admiral TV and have concluded it is a very decent design.

Looking under the hood today, . . . . . . When I was Repairing it about 7 years ago I did not replace all the capacitors.

The .25 in the AGC buss doesn't show leaky but the AGC was a little wonky after a 2 hour view, so I replaced it.

I had re-capped the sweep section, however one of the original .005 at 10,000 volt caps is still in the HV circuit and showing no sign of failure so far.

I put new ASC in the vertical and have a pair of ceramic .001 in the Horizontal sweep.

I was trying to determine if this set was the 5U4 version or 5Y3 version, I have reverted back to the 5Y3 as the B+ is running about 275 volts DC. The transformer doesn't measure the secondary resistanc the Riders say for either the 5Y3 or 5U4. Line voltage is 120 VAC now days and I believe in 1948 you were lucky to get 110 VAC.

I also notice the centering and focus run to one end of the pots, although there is enough room to center.

Next step is to order a can electrolytic as they are being made again as original and get rid of some clutter. I found one that is quite close to original value with slightly higher voltage rating.

I also replaced the .05 to ground at the voltage divider for G-1 of the audio output tube. This tube not only serves as an audio amp but is also a series regulator for the RF circuitry. The B+ (275 V) is applied to the plate through the audio output transformer. G-1 is connected to a voltage divider that biases the grid to +120 volts. The cathode will follow until the grid to cathode cuts off the tube and thus regulates the voltage used by the RF -- IF section to something like 125 volts. No matter how high the audio is turned up I never see audio in the Regulated B supply.

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Mar Mon 16, 2020 8:29 pm 
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Location: Phoenix, Arizona
I ordered up the can Electrolytic for my Admiral 19A1.

The original can Electrolytic is a 30 / 30 / 20 @ 350 Volt four lug twistloc.

I find a 30 / 30 / 30 / 30 / @ 475 Volt four lug and I have placed the order from AES.

Tghe extra 30 can be used for one of the other electrolytics and clean up the underside of the chassis and get rid of the scabed in tubulars.

It was interesting to find these can electrolytics are being manufactured as original. There is a video posted on the web of the process.

The interest in Gituar tube type amplifiers is what has driven the manufacture of these things.

Jim


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 Post subject: Re: Admiral 19A11S & Faudell & White's brilliant circuit.
PostPosted: Mar Tue 17, 2020 12:09 am 
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jimmc wrote:

The interest in Gituar tube type amplifiers is what has driven the manufacture of these things.

Jim


Yes, I have been using these new-manufactured twist lock types for over 15 years now, I buy them from AES. I have not had to replace any of this type yet and find them very good.


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