9 inch CRT for Bush TV22
 

Hello,

today I have got a Bush TV22 with a bad MW22-16 (crt is heating, but has no emission).Do you have an idea whether I could replace the crt by an American equivalent? It must be a 9 inch tube with round screen.

Here are some photos of the tv set:

http://bs.cyty.com/menschen/e-etzold...ovisorisch.JPG
http://bs.cyty.com/menschen/e-etzold...ovisorisch.JPG
http://bs.cyty.com/menschen/e-etzold...ovisorisch.JPG
http://bs.cyty.com/menschen/e-etzold...ovisorisch.JPG
http://bs.cyty.com/menschen/e-etzold...ovisorisch.JPG

Regards,
Eckhard

Hi Eckhard:

I believe that the closest tube we have is a 10BP4 which is 10 inches in diameter and about 1 inch longer than a MW22-16. I'm not sure if it would be possible to make that fit into that Bush set.

Can you believe that it has already been a year that I visited you in Germany!

Steve

As time goes by... yes, it is one year. I remember, when we have eaten white asparagus. The asparagus season in this year is late because we had a long and cold winter this year.

A 10BP4 might be really to long, there is not enough space for the neck in the back. I will keep this set as it is and will wait until I have an opportunity to get a MW22-16.

Regards,
Eckhard

...

Are there CRT rebuilders in Europe? If not I guess you could send it to Hawkeye, I would think they could fix the old one up. Might even be possible to modify a dud 10BP4 to work? Either fix would be expensive though.

Hi, it is definately not possible to use a 10BP... in a TV22. This tube is much
to big.
But I need a 10BP4 for my Tesla 4001. The original is a 25QP20. With some
mechanical mods it was possible to use a 10KP7. OK P7 is not a TV phosphor,
but it is acceptable. I have an other Tesla, so I need an other 10 inch round
tube.

Regards,
Darius

crt's
 

How about a 10Rp4 or is it an 10Sp4 - it's shorter than a 10 bp4 and it's aluminised. For that matter,a round CRT from an RCA camera viewfinder might fit the bill,too as it isn't a 10 inch tube- it has a smaller screen and shorter length. Also aluminised in the versions I've had. If I had a tube manual in front of me , I'd look it up for you.
I've seen them come up on Ebay, usually going without a single bid.
Most of the people selling them have no idea what they are supposed to be used in so the descriptions suffer.

Good Hunting !

Bob Hodge :thmbsp:

Hi Bob, where can I find a datasheet of it?:confused:
Do you have a foto of this crt?

Darius

crt's
 

I'll try and find what I have this weekend. I still have boxes which never got unpacked after the big move 2.50 years ago.
I know I have some info on these tubes as I once owned an RCA I.O. camera which had a VF which used the tube I'm remembering.
When I sold the cameras and a CCU to Danny Gustafson, I'm pretty sure I kept what literature came with it.
The number doesn't appear in any of the RCA consumer tube manuals I looked at last night so it has to be a "special purpose" tube.

I'll get back to you and post it to the list Monday! :thmbsp:

Best ,
Bob Hodge

Hi Darius,

Good news and bad news. The bad news is I have no literature on those tubes. The good news is I have the following tubes that might fit : 7tp4 ( RCA TK 111 viewfinder CRT) , 7bp4 ,10sp4 ( RCA TK111 CCU ), 9lp7. Condition unknown but all have good getters at least. My crt tester isn't working right now, but I can probably get it running. The 7bp4 ( Dumont ) , 10sp4 ( RCA) are new old stock. The 10sp4 is definately shorter than a 10bp4.
I have some 5 inch , but suspect that they would be generally too small.
And I'd like to try and find a set that needs a 5Ap4 or 1802p4 for my collection.
The 7tp4 and 10sp4 are aluminised. The 7tp4's have a very slight ion burn to the screens.

Might someone on the list have info on these types ?

And how to post pictures? I'm a bit of a fossil when it comes to things like that.

I'd give getting the tester going a shot if any of these types is of if interest. The price for any of them would be not much more than the cost of good packing and shipping. Better they get used than sitting another 15 years in the attic.

Best Regards !
Bob Hodge

Hi Bob, thanks for looking.
The 10sp4 seems interesting.
Has it a round flat screen? how long is the bulb? how long is the neck?
How thick is the neck?

Kind regards
Darius

10SP4=10 1/2" roundface,17" long,grey faceplate,50 deg deflection angle,retma base is 13m,...Electrostatic focus....,2nd anode voltage is 14kv,G2 is 410 volts,G1 (cutoff) 18-48 volts

This sounds good. What means:"retma base is 13m?"
Is the faceplate flat? How much is the diameter of the neck?
Thanks,
Darius

10sp4
 

I'll try to get an acurate measurement tonight. But I really think I ought to test it, just to be safe .

Pragmatically Yours,

Bob

the spec book says its flat,but i mistyped the base,and is 12M..so its a regular 12 pin base is wired a little different,(pin 6 looks like is connected to a focus anode)so the gun has an extra electrode.. prob for the focusing element as it is elect static focus and not magnetic like a 10bp4..

Bob, the only sets that use the 5AP4 are the prewar Andrea 1-F-5 and KT-E-5. The 1802 P4 (5BP4) was used in all the other 5 inch prewar sets from RCA, GE, Meissner, etc.

There were also some home made postwar sets made with the 5BP4, but no production sets.

I think I can test out the pinout. The tesla TV set has a focusing coil.
I can switch it off and make elect static focus. Haven't tried something
like this, but I am sure I can make it working. In the Tesla with the 10KP7
I had much problems to mount the coils. I had to dissassemble the
duodecal soket first (horrible!).

Darius

there are other 9" crt's for tv use listed.(round)
9AP4
9CP4..
8AP4..

5ap4
 

Thanks Steve,

That helps fill out the history as the box the tube came in has an Andrea mailing label on it. It also has a very supple rubber mask. The tube turned up at a hamfest in Cortland N.Y. - No chassis to be found.. glad to have found the tube !
I'll hold onto the 1804- miracles still happen !

Many Thanks Once Again !

Bob :thmbsp:

CRT for Bush
 

I'll be able to borrow a good CRT tester next week and will test the tube. I will be able to get measurements for the glass tomorrow. The face is definately flat.

Tired In Syracuse. Gotta Get Some Shuteye !!

Bob :banana: :D

I don't think the 10SP4 will fit in a TV22. The shell is about the same size as the 10BP4, with a shorter neck. The face is completely flat, and I think the diameter is too large to fit.

Meanwhile I have got a 9" spare tube from a guy in a neighbor village which will fit. It was pure coincidence. I never talked with somebody here that I am looking for a 9" tube.

One day, the telefon rang and he was on the line. I did not know him, but he asked me whether I want the tube. He is cleaning out the attic. After some discussions--he wanted 100 EUR for it-- I got it for 40 EUR.

It is a MW22-1. But I have reduce the filament voltage down to 4 volts. Here are some pictures:

http://bs.cyty.com/menschen/e-etzold...img/MW22-1.JPG
http://bs.cyty.com/menschen/e-etzold...W22-1anode.JPG
http://bs.cyty.com/menschen/e-etzold...MW22-1neck.JPG

Eckhard

Wow, Eckhard, PLEASE be careful w/that thing-it looks even MORE fragile than our 7JP4s & all that....

Yes, it is really nice. It is a Valvo tube, made in 1938. I did not know that it is a prewar tube when I have bought it. I thought it was from the early 1950's. But when I was at home again and checked the socket, I thought that I have never seen such a crt socket before.

Eckhard

:banana: So the 10SP4 is exactly what I need for my Tesla, Bob .

Darius

Hi Darius, ask for it in the Television Swap Board.

Eckhard

10sp4
 

Sorry I took so long to get back.

The 10sp4 has excellent emmision and cuts off properly.

Would $30.00 for purchase plus shipping be workable?

Let me know and I can get it boxed properly and out the door this weekend.

Best !

Bob

:thmbsp:

Yes Bob, I'll sent you a PM.

Darius