A Score on a 1957 Admiral TS104 But.....

[Chris K]

Beautiful cosmetic condition but the 10ABP4 CRT is...as Shango would say...ROACHED! It looks like someone was in it and tried to deal with the CRT pins as the rear plastic socket is loose and the pins have solder residue all over them. So much so, it's difficult to get the tester socket on it. There's no filament continuity on the tube so it's a gonner. I won't be getting to this project for some time (still working on the Pilot and a Motorola VT-71 is next in line) but a real quick search tells me these CRTs are not easy to come by. Has anyone worked on one of these and had success finding a replacement CRT or has been successful with a substitute?

Thanks all

Chris

[Yamamaya42]

I would not give up on it until you can get the socket off completely, and check the wires at the CRT going in for the heaters, if they STILL check open THEN ALL IS LOST,

otherwise there just may be REALLY crappy solder work that could be fixed by CAREFULLY removing the socket and threading back on.

[Chris K]

Originally Posted by Yamamaya42

I would not give up on it until you can get the socket off completely, and check the wires at the CRT going in for the heaters, if they STILL check open THEN ALL IS LOST,

otherwise there just may be REALLY crappy solder work that could be fixed by CAREFULLY removing the socket and threading back on.

Yes I’ll heat it up carefully with a heat gun, remove the pin socket and check the continuity on the bare wires. It’s a shame…it’s all there including the rear mounted antenna that is in perfect working order

[bandersen]

Yes, I've worked on a few. The 10ABP4 is hard to find and there is no sub. Best source is from another set. Good luck.

[Jeffhs]

Originally Posted by bandersen

Yes, I've worked on a few. The 10ABP4 is hard to find and there is no sub. Best source is from another set. Good luck.

I sincerely hope the OP gets this set working. The last time I saw a small Admiral portable TV like this one was when one showed up in our electronics lab in high school, in the early 1970s; probably a donated set or one which had been brought in for repairs (the latter under the watchful eye of our electronics instructor, of course). The TV looked to be in good shape, although the two-tone cabinet, with the name Admiral molded in gold letters into the base of the CRT mask, had a notice taped to the top, near the rabbit-ears antenna. The notice warned against using the TV before a certain hour of the evening, probably 8 or 9 p.m. EST (probably so the set wouldn't be used until the kids in the family finished their homework; at that time, however, there wasn't much, if anything, in the way of undesirable programming on TV when this set was new, or until at least the '80s--how times have changed).

I have no idea whether the set worked when we got it in our electronics lab at school, although my best guess is it had the usual problems a 1950s TV would have developed by the mid-1970s, including having a brightener on the CRT. The tube may have been quite weak by this time depending, of course, on how much the TV was used. Speaking of the CRT, I don't remember (or maybe never knew) what type tube was in the set although, judging from the size of the cabinet and of the CRT mask itself, my very best guess is it may well have had a 10- or 11-inch tube, as the TV itself was quite small. The entire TV probably didn't weigh very much either, as it did not have a power transformer (IIRC, although as small and lightweight as the set was I would not have expected to see a power transformer anywhere in or on the chassis; the lack of a 5U4 or other type LV rectifier tube would have been another dead giveaway that this TV's tubes were series-strung, not to mention the chassis being "hot" with the full line voltage if such were indeed the case).

I had no idea either, until now, that a 10ABP4 CRT is, as we say here on VK, unobtanium. I was very surprised as well to learn from your post there is no substitute for it. What was or is so special about a 10ABP4 CRT, anyway, that this tube (or a substitute for it) is either unavailable, period, or very difficult to find if there is a substitute for it somewhere (unusual screen size, special voltage/current requirements, etc.)? The tube must be very rare if the best advice for finding a substitute would be to get one from a junker TV.

[Notimetolooz]

Originally Posted by Chris K

Yes I’ll heat it up carefully with a heat gun, remove the pin socket and check the continuity on the bare wires. It’s a shame…it’s all there including the rear mounted antenna that is in perfect working order

I would not use a heat gun. Use a solder sucker on the ends of the pins while you hold a iron on the side of the pin. Usually only just the tip of the pins have solder in them.
Bob just recently made a video that included putting a base back on.
I'm surprised he didn't mention it.
Be sure to use a good adhesive around the base.
https://www.youtube.com/watch?v=NR35NufelYM
Oh, I would have used bare wire to extend the ones on the tube and just used extensions about 4 inches long joined on. Then thread the wires through the pins all at once. That way you don't have the base hanging on the wires while you attempt to solder more extensions on.

[bandersen]

I believe the 10ABP4 was the first CRT designed for portable use. It has a large diameter neck with 12 pin base like a 10BP4. Also, non-aluminzed with ion trap magnet. I think 10" with this deflection angle and base style was quicky phased out as technology improved.

Here's one I was recoating with Slip Plate. Small screen, huge neck.

[Tom9589]

I remember this model well. Someone gave me a non-working set and I fixed it up for my grandmother who was moving to a retirement facility and needed a small TV. Yes, it could be a bear to get the thing apart for service. However, when I finished it, it worked without further repairs for five years. The paint was not in the best of shape, so I defiled it and painted it bright blue. I have better taste in paint now. I do remember the strap on the base of the CRT for adjusting the focus.

[trinescope]

Another similar tube by RCA was their 8DP4, it has an extra pin on the base for focus voltage.

[Tube TV]

They're a really cute little tv. I almost bought one last year.

[Electronic M]

I just realized I have the same admiral portable discussed here... I'm also realizing I've been building a nice collection of painted metal 50s portable TVs without trying. I swear this stuff breeds when ya aren't looking

Originally Posted by trinescope

Another similar tube by RCA was their 8DP4, it has an extra pin on the base for focus voltage.

Ironically I just did one of those RCA 8-PT-7030(?) Portables that use it on Thanksgiving....It had an old partial recap that I finished before realizing that probably the main reason it lacked raster despite having H Osc whistle was that the HV rectifier was gassy...My "I'm not at home and don't have my usual parts stock" solution involved series stringing 1N4007s, and it worked.

[Chris K]

Originally Posted by Tube TV

They're a really cute little tv. I almost bought one last year.

Here are some pics the seller took of it. It's in great shape...outside!

[Chris K]

Originally Posted by bandersen

I believe the 10ABP4 was the first CRT designed for portable use. It has a large diameter neck with 12 pin base like a 10BP4. Also, non-aluminzed with ion trap magnet. I think 10" with this deflection angle and base style was quicky phased out as technology improved.

Here's one I was recoating with Slip Plate. Small screen, huge neck.

Yes I saw these pictures on Flicker...so envious. I plan to do the delicate surgery but I think the odds are against reviving mine. Are these tubes as rare as folks are saying? Am I probably going to need to buy a donor set in the end Bob?

[Chris K]

Originally Posted by Notimetolooz

I would not use a heat gun. Use a solder sucker on the ends of the pins while you hold a iron on the side of the pin. Usually only just the tip of the pins have solder in them.
Bob just recently made a video that included putting a base back on.
I'm surprised he didn't mention it.
Be sure to use a good adhesive around the base.
https://www.youtube.com/watch?v=NR35NufelYM
Oh, I would have used bare wire to extend the ones on the tube and just used extensions about 4 inches long joined on. Then thread the wires through the pins all at once. That way you don't have the base hanging on the wires while you attempt to solder more extensions on.

Yes I remember seeing someone do the re-soldering of the leads after he extended them with copper wire strands pulled from a lamp cord. Long leads will certainly make threading them through the pins all at once much easier. I saw shango replace the pin cap on a CRT with about a dozen leads in play but he didn't extend them and it was an all through or nothing task. He, of course, did it though!

[Yamamaya42]

Most here can agree that shango is a bit... Odd