GORGEOUS RCA CTC-16 Console on eBay!!!!

[bandersen]

You need to go an ETF swapmeet. That list is only the museum's inventory. Individual sellers have a bunch.

[Yamamaya42]

If it wasn't a 1300 mile drive from here, I'd would think about doing it some time!

[Chris K]

Wow. Got the 10BP4…need a 12JP4 for The Doghouse! Also need a 17DKP4. Do these rarer tubes ever turn up in decent condition with any regularity? I’d also love to find a new or close to new 17 inch for the Predicta. I’d open the bank account for that one and the 12JP4!!!!!!

[Electronic M]

Originally Posted by Chris K

Wow. Got the 10BP4…need a 12JP4 for The Doghouse! Also need a 17DKP4. Do these rarer tubes ever turn up in decent condition with any regularity? I’d also love to find a new or close to new 17 inch for the Predicta. I’d open the bank account for that one and the 12JP4!!!!!!

I've got a healthy 17" tube that will fit a predicta. The neck is about an inch longer so you'd have to mount the back hatch on standoffs. $150 local pickup or delivery to the ETF only (I don't want to box it).

[Chris K]

Originally Posted by Electronic M

I've got a healthy 17" tube that will fit a predicta. The neck is about an inch longer so you'd have to mount the back hatch on standoffs. $150 local pickup or delivery to the ETF only (I don't want to box it).

Thanks Tom but I made an error. The Princess has a 21" screen so I need a 21EAP4. Unfortunately, I don't think electronic swap meets happen very often in my area so old and working CRTs are hard to come by. I have purchased 2 from the ETM but, right now, they don't have anything I need in stock.

Chris

[Electronic M]

Originally Posted by Chris K

Thanks Tom but I made an error. The Princess has a 21" screen so I need a 21EAP4. Unfortunately, I don't think electronic swap meets happen very often in my area so old and working CRTs are hard to come by. I have purchased 2 from the ETM but, right now, they don't have anything I need in stock.

Chris

No, you're making an error now. The Princess is a 17" set. I know because I used to own one (I could also find some service info to quote if you don't believe me).

The only 21" table set is the wood cabinet Holiday model.

The only way a 21" Princess exists is if an owner swapped a Holiday or console headshell onto a princess (the top halves of the swivel collars and electrical connections are the same so the swap only requires 1 screw and 4 wire connectors be interacted with).
Philco never sold a 21" princess new.

[Yamamaya42]

Originally Posted by Electronic M

No, you're making an error now. The Princess is a 17" set. I know because I used to own one (I could also find some service info to quote if you don't believe me).

The only 21" table set is the wood cabinet Holiday model.

The only way a 21" Princess exists is if an owner swapped a Holiday or console headshell onto a princess (the top halves of the swivel collars and electrical connections are the same so the swap only requires 1 screw and 4 wire connectors be interacted with).
Philco never sold a 21" princess new.

So... what you are saying is, that a 21" Princess is a Philco Predicta Frankenstein!

[bandersen]

Originally Posted by Chris K

Wow. Got the 10BP4…need a 12JP4 for The Doghouse! Also need a 17DKP4. Do these rarer tubes ever turn up in decent condition with any regularity? I’d also love to find a new or close to new 17 inch for the Predicta. I’d open the bank account for that one and the 12JP4!!!!!!

Not really - Predicta compatible CRTs get snatched up quickly.

Are you sure you want a 12JP4? Remember it has no ion trap and will develop an ion burn. I'd suggest going with a 12QP4 to avoid this. 12LP4, 12KP4 or similar might be possible, but they have a different anode connector and are longer.

[Chris K]

Wow...same melt on mine. What a mess. Yes, I saw some threads regarding the 12QP4 substitution. Are the required changes fairly simple? FYI I have the Predicta tube wrong. The Princess is the 21" version so I will need to source a 21EAP4

[Chris K]

Originally Posted by bandersen

Not really - Predicta compatible CRTs get snatched up quickly.

Are you sure you want a 12JP4? Remember it has no ion trap and will develop an ion burn. I'd suggest going with a 12QP4 to avoid this. 12LP4, 12KP4 or similar might be possible, but they have a different anode connector and are longer.

I have an opportunity to buy a NOS 12QP4 Bob. Is it a direct replacement for the 12JP4? Do I need an ion trap for 12QP4?

[bandersen]

Originally Posted by Chris K

I have an opportunity to buy a NOS 12QP4 Bob. Is it a direct replacement for the 12JP4? Do I need an ion trap for 12QP4?

Datasheet says it needs an external ion trap magnet. Here are the links so you can compare the dimensions.

https://frank.pocnet.net/sheets/127/1/12JP4.pdf

https://frank.pocnet.net/sheets/127/1/12QP4.pdf

[Chris K]

Originally Posted by bandersen

Datasheet says it needs an external ion trap magnet. Here are the links so you can compare the dimensions.

https://frank.pocnet.net/sheets/127/1/12JP4.pdf

https://frank.pocnet.net/sheets/127/1/12QP4.pdf

Thanks so much Bob. Looks like the datasheet for the 12QP4 has an error maybe? It says pin 10 no connection but it's G2, the same as the 12JP4. Looks like things line up well. The 12QP4 might have a slightly larger screen diameter but looking at the chassis and cabinet, it shouldn't be a problem.

[Chris K]

Originally Posted by bandersen

Datasheet says it needs an external ion trap magnet. Here are the links so you can compare the dimensions.

https://frank.pocnet.net/sheets/127/1/12JP4.pdf

https://frank.pocnet.net/sheets/127/1/12QP4.pdf

The seller has the original ion trap magnet and is including it in the purchase. Yaaaaaay! I'll be in the Doghouse for the next couple of months. Sorry Motorola VT71...back on the shelf for you...again. No luck at all with getting the video. No signal and no failed parts.

[bandersen]

Originally Posted by Chris K

Wow...same melt on mine. What a mess. Yes, I saw some threads regarding the 12QP4 substitution. Are the required changes fairly simple?

I've never tried it, but it's my understanding the 12QP4 is a drop in substitute. Others will require you to cut off the anode connector and install a different type. The longer CRTs might not fit in the cabinet with the back on or require you to move the focus coil/yoke assembly further back.

The Princess, Debutante and Siesta have a 17" screen. Holiday, Pedestal and Tandem are 21"

If you need a 21", you are much, much better off with a 21FDP4 (or equivalent) than the original, flawed 21EAP4.

[bandersen]

I believe they made a 21" Princess model in Brazil. I don't think the 21" head will fit on a Princess cabinet. The CRT also has different specs.