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Old 06-15-2018, 05:48 PM
mbates14 mbates14 is offline
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Sencore CR161 modern CRTs?

So I picked up a CR161 off of Fleabay for a reasonable price. its in very decent condition, almost mint, has adapter 1 through 11 but thats it.

Seems to work fine, I stuck it on a porthole I just got which has a 12LP4, took a bit to wake up but it woke up and had shown cut-off and emissions very close to the end of the meters travel. So thats a plus.

But the reason why I am posting this thread, is I collect alot of vintage computers too which contain 80s, 90s CRTs so I would like to be able to test Trinitron monitor CRTs, as well as standard monitor CRTs and black and white CRTs from the 80s/90s.

But I quickly realized that none of the adapters fit modern color CRTs, and especially the trinitron as it has dual focus anodes.

Also, there was an adapter that fit my 9" black and white CRT but it wasnt getting cut-off at all, and it seemed weak. But it was nice and bright in the computer monitor so somethings up, it may not be the right adapter for that either.

Are there any after-market adapters, or universal clip-lead style adapters for this thing? or is there a schematic/pinout sheet to adapt it to modern CRTs? or?

any ideas?
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Old 06-15-2018, 09:01 PM
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Electronic M Electronic M is offline
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Simple method make your own universal CRT adapter using the base from a dead old tube like a 12LP4 (or a brightener for one), some wire, and some alligator clips. That is what I did for my B&K 466...The connector the adaptors plug into is the same connector it uses for 12LP4s and the like so it was the easiest for me to make an adaptor for. All I have to do is look up the pinout for loose CRTs I want to test. For tubes in sets as was the case of the 15GP22 in my CT-100 I just used the color code from the chassis socket wiring to plan out the connections. I only have my universal adapter wired for one gun since there is only one meter on my tester.

You may want to look up the datasheets on the newer CRTs since some odd heater voltages, low focus and or G2 voltages and unusual pinouts came to be around the advent of inline gun CRTs. Some older tubes used odd heater voltages too but it is usually easy to figure out which.

If you test a lot of some category of tube it may be worth it to find a socket and make a dedicated adapter.
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Old 06-16-2018, 06:34 AM
mbates14 mbates14 is offline
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Thanks for the advice.

However, I dont have any pinouts. Also my 12LP4 only has like 5 or so pins. the tester has a ton more than that on its socket. Not sure what the color codes are either, it says nothing in the book?

The only vintage color tube I have is my 21FJP22 which the base is destroyed on, but the tube still works. Need to find a base and replace that some day.

Most of the stuff I will be testing is modern"ish" with the 7 pin B&W tubes, but more importantly modern color tubes. such as the Trinitron CRTs, etc.
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Old 06-16-2018, 10:20 AM
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Electronic M Electronic M is offline
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Google a CRT type number plus the word datasheet. There are a number of tube datasheet sites that have datasheets for CRTs. Those sheets include pinouts. Of course, your tester has many more pins than a monochrome CRT the extras are so it can support a socket with 3 guns. My B&K 466 it's main connector which is a socket for the early monochrome types has much more than the 5 contacts wired into the tester, and I could easily add more wires to my universal adapter to connect to all leads of a CRT, but there is too little advantage to that in the normal use of the tester for me to bother.

Color code for color CRTs Brown=heater, black=focus (my tester don't need a connection to focus), Yellow (with R, G, or B stripe to designate which gun)=Cathode, solid color(R, G, or B)=Grid 1, White(with R, G, or B stripe to designate which gun)=G2. Many testers only need Heater, Cathode, G1 and G2 to work.
Monochrome had a different color code (which occasionally varied) I can parse one out for you if you need to know.

Look for a brightener for that 21FJP that is a good source for a base.
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Last edited by Electronic M; 06-16-2018 at 10:23 AM.
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Old 06-17-2018, 07:04 PM
mbates14 mbates14 is offline
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Yea I would have never known that color code.

As far as a brightener, thats a good idea. Never thought of that. Will check ebay and see what I find. The base was good before the TV turned up "missing" for a gap of time and returned to me. it was returned with the base crushed, fearing the worst I warmed it up and luckily it still had shown a raster. I thought for certain that CRT was a goner. With the tuner pieces missing/broken, etc I would have scrapped it at that point.
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Old 06-20-2018, 07:11 AM
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zeno zeno is offline
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Most modern color CRT sets used a PCB on the socket and
are marked. You can also usually see at least the filament
in the tube & usually the other elements.
Some in-line CRT's Zenith & RCA & others have spring contacts.
You can carefully remove the plastic key so you can grab them
with the hooks. Dont know what they call them but use the
hook type test lead ends ( not alligator) , they hold on best &
dont short out.

73 Zeno
LFOD !
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