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lutiana
February 24th, 2017, 04:44 PM
Ok, so any CRT experts out there, what are the chances that this tube: http://www.ebay.com/itm/Cal-Comp-model-TP862-01-13-Color-monitor-/161255221382?hash=item258b8f6886:g:jxIAAOxy039TK5C Q would be transplantable into my brocken 5145 monitor?

The sizes are the same (13"), so I am thinking if it fits I could just take the tube and the bit that attaches to the back of it and leave the rest of the 5145 circuitry in place. Sound feasible? Or is there more to it than that?

compu_85
February 28th, 2017, 07:55 PM
If both tubes have the same number of pins on the gun it will most likely work. (Watch for Ian to correct me on that :) )

What model tube is in your 5145? I'd try to find its data sheet, and compare to the perspective tube.

Agent Orange
February 28th, 2017, 08:05 PM
Ok, so any CRT experts out there, what are the chances that this tube: http://www.ebay.com/itm/Cal-Comp-model-TP862-01-13-Color-monitor-/161255221382?hash=item258b8f6886:g:jxIAAOxy039TK5C Q would be transplantable into my brocken 5145 monitor?

The sizes are the same (13"), so I am thinking if it fits I could just take the tube and the bit that attaches to the back of it and leave the rest of the 5145 circuitry in place. Sound feasible? Or is there more to it than that?

Generally, if the pins line up and the yoke fits it may work. But, some of the gotchas are filament voltages, etc. See if you can get the specs from Sam's or on line somewhere. You need the tube number from the one on Ebay.

lutiana
March 1st, 2017, 06:52 AM
If both tubes have the same number of pins on the gun it will most likely work. (Watch for Ian to correct me on that :) )

What model tube is in your 5145? I'd try to find its data sheet, and compare to the perspective tube.

The dead tube is a Samsung 3701B-22-ND (See here for a picture here (http://www.vcfed.org/forum/showthread.php?55798-Tube-for-an-IBM-5145-Monitor&p=443528#post443528)) and if you have any info on it that would be great as I could not find anything on google about it. I have also just sent a note to the seller asking if they can tell me the model number on the tube.

KC9UDX
March 1st, 2017, 07:28 AM
Generally, if the pins line up and the yoke fits it may work. But, some of the gotchas are filament voltages, etc. See if you can get the specs from Sam's or on line somewhere.

I used to think that (been fixing TVs on and off for 30 years, did an awful lot of it 20 years ago) but in recent years, for whatever reason, I find that filament voltages are all 12.6, and tube element configuration, even with the same number of pins, is a total crapshoot. But maybe I've just been pcking oddball tubes to work with.

lutiana
March 1st, 2017, 10:07 AM
Seller says the tube is a Hitachi model M34JCA30X13(J), but goes on to say it has some burn in, so I am not too sure if's a great candidate for the swap, but it would be helpful to know if it would work regardless.

Agent Orange
March 1st, 2017, 11:55 AM
I used to think that (been fixing TVs on and off for 30 years, did an awful lot of it 20 years ago) but in recent years, for whatever reason, I find that filament voltages are all 12.6, and tube element configuration, even with the same number of pins, is a total crapshoot. But maybe I've just been pcking oddball tubes to work with.

I'm not clear sometimes. I'm wasn't challenging the A+ value. My point was that you don't want to end up with B+ on the filament due to some odd pin alignment. You really need the specs if you're about to do a mod install.

KC9UDX
March 1st, 2017, 01:15 PM
I'm not clear sometimes. I'm wasn't challenging the A+ value. My point was that you don't want to end up with B+ on the filament due to some odd pin alignment. You really need the specs if you're about to do a mod install.

I understand, and was not trying to dispute your information, especially because it agrees with my past experience. But I wonder if you've noticed what I've encountered in recent years, or if I'm just working on a small subset of TVs and monitors that just happen to be this way.

I think you did make the point that it's a bad idea to buy a monitor for a tube swap without first actually colliding the specs. If that wasn't clear to anyone, I'm writing this to stress the point.

lutiana
March 1st, 2017, 01:41 PM
I think you did make the point that it's a bad idea to buy a monitor for a tube swap without first actually colliding the specs. If that wasn't clear to anyone, I'm writing this to stress the point.

Yes, I got that and came to the same decision, especially since the one on ebay has burn in. I am not willing to gamble $150 on the off chance that it would work. However, given the lack of any real documentation that I can find online it may come down to a pure gamble if I really want to get the monitor working again (and I do).

ki4swy
March 1st, 2017, 02:13 PM
post the two tube numbers and i can look them up in my cr7000 rejuv and see if it has same specs ( socket/heatervoltage/bias ) , you will want to use the original yoke.

lutiana
March 1st, 2017, 02:27 PM
post the two tube numbers and i can look them up in my cr7000 rejuv and see if it has same specs ( socket/heatervoltage/bias ) , you will want to use the original yoke.

Samsung 3701B-22-ND - Broken Tube

Hitachi model M34JCA30X13(J) - "New" tube


If possible could you post some model numbers of tubes that would be drop in replacements? I think if I had a few monel numbers to look for I may have some better luck. Or it could help me ID some monitors that I could land and transplant,.

Hugo Holden
March 9th, 2017, 04:37 AM
Some related information might help, the CRT used in a 5153 is the 370RKB22-TC14, which has a direct Hitachi replacement which can be supplied by newtubes on ebay as I recall. The CRT used in the 5154 is the M34JDU30X15 and both these crts have a satisfactory phosphor pitch for CGA or EGA images. The basic electrode structure of each of these is also the same and the base pinning looks the same too. I'm not 100% sure if the heater voltages match. Possibly one of these tubes could sub in for the broken tube in your 5145. Suggest contact newtubes as they appear to have an extensive equivalents list and will know which is the closest equivalent to your broken tube.

lutiana
March 9th, 2017, 06:59 AM
Some related information might help, the CRT used in a 5153 is the 370RKB22-TC14, which has a direct Hitachi replacement which can be supplied by newtubes on ebay as I recall. The CRT used in the 5154 is the M34JDU30X15 and both these crts have a satisfactory phosphor pitch for CGA or EGA images. The basic electrode structure of each of these is also the same and the base pinning looks the same too. I'm not 100% sure if the heater voltages match. Possibly one of these tubes could sub in for the broken tube in your 5145. Suggest contact newtubes as they appear to have an extensive equivalents list and will know which is the closest equivalent to your broken tube.

I have contacted them. Thanks a ton for that lead, hopefully they can help and have an appropriate tube.