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Lisa CRT replacement

snuci

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Nov 22, 2012
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Richmond Hill, Ontario, Canada
Well, I started a thread "Sadly, one less Lisa in the world" and I thought I'd start a new thread because I decided to try to replace my CRT without having to resort to buying a CRT in chassis... yet.

With the encouragement here, I think I may give this a shot. I figured I'd document this here in case any other poor soul gets a Lisa with a CRT broken in shipment.

Here's what my CRT neck looked like when I got my Lisa:

small_IMG_00000016.jpg


My CRT markings are as follows:

Clinton Electronics 12" monochrome white phospor tube
CEULC99F1ATE
CE727M12C164GR
707-0008
E1A1240

small_IMG_00000015.jpg

From an online surplus store, I ordered a CEULC99F CRT listed as: "CEULC99F CRT AITE , 70-18349-01".

I have found no guides or hints on the Internet at how to decode the Clinton Electronics model numbers so I'm not even sure this will work. I did read in a CRT testing manual that "CEULC99F" is the model of this tube but I can't figure out much more than that. At this point, I'm taking a shot at this being close. It, apparently, comes with the yoke but I'm not sure if it will have the two vertical/horizontal separate connectors as I've seen another on eBay that is marked similarly with one solid four wire connector from the yolk.

I'll keep you guys up to date when I get the CRT. I am very sceptical that it will be a direct replacement but I thought I'd give it a shot before having to spend a larger sum to get a CRT in chassis.

If anyone has done this or have any pointers, I think I've built up enough courage to tackle this (and discharging the old tube).
 

snuci

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I forgot to add, if you have an open Lisa by any chance or you feel like taking a look, does your CRT model numbers match up or are similar? I'd love to see if they are all the same or close. I assume there are many makes and models over the years.

This would be helpful. Thank you.
 

Divix

Member
Joined
Feb 20, 2013
Messages
24
I forgot to add, if you have an open Lisa by any chance or you feel like taking a look, does your CRT model numbers match up or are similar? I'd love to see if they are all the same or close. I assume there are many makes and models over the years.

This would be helpful. Thank you.
I took a look at mine and the part numbers are the same. My date of manufacture is 4187. So 187th day of 1984. So Mid July of 1984. I find a source for tubes let me know. I have a little burn in from the last owners.

Cheers,

Nick,
 

snuci

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Location
Richmond Hill, Ontario, Canada

I'm confused. I never saw that one and I scanned the site top to bottom and the entire Internet, for that matter. Surplusssales.com is where I bought mine from. I am hoping that I got one before they knew what application it was for (good for me) and since I sent pictures, I let them know that the tube fit an Apple Lisa and now they are featuring it (bad for those who may want it because I didn't pay that much).

That said, I probably would consider it at this price knowing it's new old stock. I just hope mine is the same one. If not, I may still have to consider it :( I was going to wait to tell everyone who needed one after I got it to see if it was similar and fit. A NOS match would be awesome but I'm not that lucky or I wouldn't be in this predicament in the first place :)

Thanks for pointing this out. I have my fingers crossed.
 

Divix

Member
Joined
Feb 20, 2013
Messages
24
I'm confused. I never saw that one and I scanned the site top to bottom and the entire Internet, for that matter. Surplusssales.com is where I bought mine from. I am hoping that I got one before they knew what application it was for (good for me) and since I sent pictures, I let them know that the tube fit an Apple Lisa and now they are featuring it (bad for those who may want it because I didn't pay that much).

That said, I probably would consider it at this price knowing it's new old stock. I just hope mine is the same one. If not, I may still have to consider it :( I was going to wait to tell everyone who needed one after I got it to see if it was similar and fit. A NOS match would be awesome but I'm not that lucky or I wouldn't be in this predicament in the first place :)

Thanks for pointing this out. I have my fingers crossed.

After inspecting that CRT on that website, the wiring harness on the yoke is different from what I have set up. That crt has a square plastic piece with wires going to the tube? Mine has no square part like that with wires coming off the very tip of the yoke. So im cuious if anyone's CRT looks like the back of this one. This might have been a improved model sold later on with the same part model #. But If anyone has this type of monitor with the same wiring harness working in thier lisas maybe they could upload photos or chime in on this model?. I'm no CRT expert on this stuff.

Cheers,

Nick,
 

snuci

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Nov 22, 2012
Messages
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Richmond Hill, Ontario, Canada
After inspecting that CRT on that website, the wiring harness on the yoke is different from what I have set up. That crt has a square plastic piece with wires going to the tube? Mine has no square part like that with wires coming off the very tip of the yoke. So im cuious if anyone's CRT looks like the back of this one. This might have been a improved model sold later on with the same part model #. But If anyone has this type of monitor with the same wiring harness working in thier lisas maybe they could upload photos or chime in on this model?. I'm no CRT expert on this stuff.

Cheers,

Nick,

For reference my Lisa has a 4156 date code. Very close to yours. I think the "side" picture on that site is the under side because the anode wire hole is missing. From the top, the anode wire hole is next to the label on ours. This label is on the bottom maybe or perhaps ours have a label on the bottom too? The yoke cap had a bunch of wires off of the tip of the CRT but there are also four wires (2 for vertical and 2 for horizontal) that come out of somewhere underneath and I think it's from the square that you mention. It just can't be seen from looking from the top (at least I'm assuming this because I haven't taken the broken CRT out yet).

The yoke does look a little different but the key is if it has two 2-wire plugs (one set of two wires to one connector for the vertical and one set of two wires to one connector for the horizontal) coming from that block. I've seen a similar CRT on eBay with one four wire connector at http://www.ebay.ca/itm/Clinton-Electronics-12-Inch-CRT-Tube-CEULC99FIATEI-/190759839099 but the model number is slightly different. I'm sure there are minor variations. We'll see and I'll let you know.
 

Divix

Member
Joined
Feb 20, 2013
Messages
24
For reference my Lisa has a 4156 date code. Very close to yours. I think the "side" picture on that site is the under side because the anode wire hole is missing. From the top, the anode wire hole is next to the label on ours. This label is on the bottom maybe or perhaps ours have a label on the bottom too? The yoke cap had a bunch of wires off of the tip of the CRT but there are also four wires (2 for vertical and 2 for horizontal) that come out of somewhere underneath and I think it's from the square that you mention. It just can't be seen from looking from the top (at least I'm assuming this because I haven't taken the broken CRT out yet).

The yoke does look a little different but the key is if it has two 2-wire plugs (one set of two wires to one connector for the vertical and one set of two wires to one connector for the horizontal) coming from that block. I've seen a similar CRT on eBay with one four wire connector at http://www.ebay.ca/itm/Clinton-Electronics-12-Inch-CRT-Tube-CEULC99FIATEI-/190759839099 but the model number is slightly different. I'm sure there are minor variations. We'll see and I'll let you know.

If you tilt you lisa carefully up a little there are some vents in the plastic right next to the serial numbers. If you take a good flashlight you can see under the tube. Or you can take off the side plastic cover off the lisa as well and look easily in there. There are some small paper stickers such as "10" and looks like another small white sticker of the model # of the tube. I do hope this can work because I would love a NOS tube. If you paid a lot less it would be a steal as used ones are going for alittle more. The company Clinton Electrics is still in business and their might be some old techs that are familiar with this model. You never know untill you ask. I might give them a call or a old tube expert. I want to be 100% positive just because there are lots of volts were playing with here LOL. Im very interested in this too as mine has some minor burn in it. Thanks again for the lead :D

Nick,
 

snuci

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Messages
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If you tilt you lisa carefully up a little there are some vents in the plastic right next to the serial numbers. If you take a good flashlight you can see under the tube. Or you can take off the side plastic cover off the lisa as well and look easily in there. There are some small paper stickers such as "10" and looks like another small white sticker of the model # of the tube. I do hope this can work because I would love a NOS tube. If you paid a lot less it would be a steal as used ones are going for alittle more. The company Clinton Electrics is still in business and their might be some old techs that are familiar with this model. You never know untill you ask. I might give them a call or a old tube expert. I want to be 100% positive just because there are lots of volts were playing with here LOL. Im very interested in this too as mine has some minor burn in it. Thanks again for the lead :D

Nick,

I tried with the flashlight but I couldn't see a thing. I'll take off the side cover tomorrow and see if I can take a pic. Here is a pic from above. you can see the green and yellow wires going to the square pixel transformer (you may not have this) then to the video board. The red and white wires also go to the video board. This is in addition to the CRT tip cap wires that go to a connector further down the board that is harder to see from above.

small_IMG_00000018.jpg

On a side note, I just found a friend who has discharged many CRTs and can help me out. Woohoo! I can get it in at the end of next week but my the Lisa has no power so this is one small step. My I/O board is definitely not in good shape either due to corrosion. One step at a time, I guess.
 

Divix

Member
Joined
Feb 20, 2013
Messages
24
I tried with the flashlight but I couldn't see a thing. I'll take off the side cover tomorrow and see if I can take a pic. Here is a pic from above. you can see the green and yellow wires going to the square pixel transformer (you may not have this) then to the video board. The red and white wires also go to the video board. This is in addition to the CRT tip cap wires that go to a connector further down the board that is harder to see from above.

View attachment 12226

On a side note, I just found a friend who has discharged many CRTs and can help me out. Woohoo! I can get it in at the end of next week but my the Lisa has no power so this is one small step. My I/O board is definitely not in good shape either due to corrosion. One step at a time, I guess.

Thats great man. Its cool you have that 2mb boards in there. The premade one you can buy these days is very expensive. If you can get it up and running it will be pretty sweet. Keep us posted,

Nick,
 

snuci

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I just got my CRT delivered by UPS. It came in one piece and was well packed with warning stickers all over and packed face down. Looks like they've shipped one or two of these before :) Appearance-wise, it looks fine. I don't think mine is new old stock but it wasn't advertised as new. That said, I won't know until I plug it in. FYI, it's got a Digital Equipment sticker on it :)

Here's a pic:

IMG_00000022.jpg

(Sorry, I think I just downloaded the normal size file)

You'll notice that the wires coming off the yoke are in one connector. This is different from the Lisa but the wire colours are the same Yellow/Green Red/Brown. The brown wire in my Lisa was pretty faded so I thought it was white. This also has what appears to be a degaussing coil to one side? Unless it's on the bottom, the Lisa doesn't have this.

I'll have to change the connectors, I think, but this should work. I'll update when I get it in but my I/O board and power supply need work (I think) so I won't be able to see what happens right away.

I believe the picture at surplussales.com is of the side and it's upside down to show you the yoke wires. Looks the same to me except where the yoke meets the big end of the tube, the yoke is slightly different from that picture.

Hope this helps.
 
Last edited:

Al Kossow

Documentation Wizard
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Silicon Valley
I'll have to change the connectors, I think, but this should work.

You need to take off the yoke from the broken tube and put it on the new one.

If that is a CRT from a DEC video terminal, it is going to be quite a bit slower than the scan
rate of the Lisa.
 

snuci

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Richmond Hill, Ontario, Canada
monochrome crts don't need, or can use a degaussing coil.

After looking on the net, I agree but I' not sure what that external loop is.

Here's a better picture:

IMG_00000023.jpg

I've looked around for a bit and haven't seen any mention of this loop or seen a picture of what that might be. If anyone knows, I'm all ears and would be grateful for helping me figure it out.
 

snuci

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You need to take off the yoke from the broken tube and put it on the new one.

If that is a CRT from a DEC video terminal, it is going to be quite a bit slower than the scan
rate of the Lisa.

I was hoping not to mess with this because it would then need adjusting (I assume). If this is my only hope, I will try it. Does anyone have any other thoughts on if changing the yoke is a must?
 

RWallmow

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Anoka, MN USA
Monochrome CRT yoke don't need much adjusting.. Needs to be the right deflection angle though.

Yeah, there is really very little to monochrome yokes, worst case the image is a bit crooked if you aren't lined up quite right once you swap the yoke in.
 

orion3311

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Dec 26, 2012
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PA
You need to verify that the new yoke is compatible. Find out which pair of wires is horizontal and which pair of wires is vertical. Using a meter, get a resistance reading from each pair, then compare that reading to the old yoke (or vice-versa depending on which one you start with). If each reading is within a few ohms of the other, you're good, swap it in. If one or both readings are drastically off (50 ohms instead of 3 ohms), then you'll need to swap the yoke. On a monochrome, a lot less to work about with yoke swapping, as long as its installed snug against the bumpers minimal adjustment should be required.

I did a write-up for arcade monitors, some of which may apply: http://www.junknet.net/tube-swap-diy-part1
 
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