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I'm not in familiar with it. Bk precision and sencore are most popular here. You will need to make sure you have proper adapt for CRT necks you want to work on. Cr-23, cr31, etc. In this case for ms9 you will be cr-23. Tester needs to be compatible with that or you can't hook it up

This is site you want for all tube spec. There is sticker on tube back that will be important..."A68......"
You type in here http://tubular.atomized.org/ that will give you setup informative for you tester.

For example you have "A68KJU96X" tube. Type in that site and it tells you heater voltage 6.3v, g1 voltage 50v and adapt socket for tube neck.
 
Yes sir. It can rejuvenate as well IF needed. That is the "restore" option on tester. Only meter can tell if you need it though. You can't tell by looking at tube so don't ever listen to anyone that just tells you to rejuvenate, especially someone seeing it over the Internet. Just like you can't tell if voltage on power supply needs adjusting just by looking at it... You need to hook up a meter and it will tell you. You don't want to attempt to rejuvenate a tube that is already good.
To a degree the measurement is useful, but... I find that by the time a tube is unable to reach a good intensity before losing focus, or oversaturating and smearing to the right, it's time to try a restore/rejuv, or it's simply EOL. Otherwise, that's what calibration controls are for on the chassis, and why we have adjustable cutoffs in the first place.
 
Yes sir. It can rejuvenate as well IF needed. That is the "restore" option on tester. Only meter can tell if you need it though. You can't tell by looking at tube so don't ever listen to anyone that just tells you to rejuvenate, especially someone seeing it over the Internet. Just like you can't tell if voltage on power supply needs adjusting just by looking at it... You need to hook up a meter and it will tell you. You don't want to attempt to rejuvenate a tube that is already good.
To a degree the measurement is useful, but... I find that by the time a tube is unable to reach a good intensity before losing focus, or oversaturating and smearing to the right, it's time to try a restore/rejuv, or it's simply EOL. Otherwise, that's what calibration controls are for on the chassis, and why we have adjustable cutoffs in the first place.
you say that even before the measurement says bad it ok to do restore/rejuv?
 
No. Rejuvenater function have specific job. They remove fine particulate that gather on cathode end to expose more barium oxide using higher than normal beam current (assuming you talk about"restore function... Not shorts etc). That's it. Not magic. It cannot restore worn cathode. Once it's worn it's worn, tube done.

If you test it measures the current from the cathode end to grid 1 and grid 2. If current measurement is good it's good. Not going to get more good after a certain point. Aka particulates aren't causing reduced current on cathode.... So why put higher than normal beam current through? What will you gain? You will be putting unnecessary high current and begin breaking down the only layer of barium oxide the cathode has and will ever have. That is exactly why you don't "rejuvenate" a tube that is good. It's a destructive process that is sometimes a necessary process on bad tubes.
 
You have piece of wood with paint on it.

You sand it down to remove paint.

You now have bare wood.

You decide hmmm maybe I should keep sanding it down.

Your wood isn't going to get "more" bare... You will just have less wood.


No need to "sand down" your cathode life away if it's current is proper.
 
No. Rejuvenater function have specific job. They remove fine particulate that gather on cathode end to expose more barium oxide using higher than normal beam current (assuming you talk about"restore function... Not shorts etc). That's it. Not magic. It cannot restore worn cathode. Once it's worn it's worn, tube done.

If you test it measures the current from the cathode end to grid 1 and grid 2. If current measurement is good it's good. Not going to get more good after a certain point. Aka particulates aren't causing reduced current on cathode.... So why put higher than normal beam current through? What will you gain? You will be putting unnecessary high current and begin breaking down the only layer of barium oxide the cathode has and will ever have. That is exactly why you don't "rejuvenate" a tube that is good. It's a destructive process that is sometimes a necessary process on bad tubes.
oh is see… that´s a critical thing to do.
if there is somebody in Germany who can do this… would be great to get some help on that.don`t want to kill tubes.
 
I have a B+K 490B. I don't know, maybe the dials on your rejuvenator are better calibrated than mine, but mine regularly shows measurements that are off. If the gun is dead, then yes, that's accurate. However, I wouldn't trust anything else.

I always go with my gut. If the tube is lacking green, I will rejuvenate the green gun. If the tube has poor focus, I will rejuvenate all three guns. Doesn't matter what the dials are showing.

There's no restore function on the 490B, however, I've always had fair results with the lower setting of the two (25mA as opposed to 50mA). I think I might have once used the higher setting and it didn't do a lick of difference.
 
Not to state the obvious but yes if you are doing any electrical measurement and your measurements aren't accurate then it's a problem haha. Need to be able to trust your meter. May be time to service/calibrate the tester or different tester... Most are getting really old now.
 
Admittedly not a bad idea. I'll see if there's a service manual for the thing.
 
Just think out loud but really is measured of current through cathode. You could likely find points to hook up any nice digital milliamps meter on it. Plug in nice fluke meter to check emissions far more accurately... Hmmm.

You bk490b manual shows you mA range a bit.
Screenshot_20191113-102622.png
 
I'm saying that, by the time a tube is in absolutely dire condition, where it's really not in a usable state, I will go ahead and hit it with the rejuv. If it doesn't obviously need it, then there's no call to do it.

What Nem wrote is pretty much exactly how I feel. The low current restore options are also really great ones to use when the tube isn't behaving ideally. If a tube's focus is poor even after adjustment, and the heater voltage is correct, then I don't know what the testing function is going to tell you. That the tube isn't very good? Anyone can tell that by looking at it. Just give it a shot with the light restore option.
 
We can discuss this but sorry op to semi steal your thread. I don't know what it is specifically about CRT rejuvenation that there is so much bad information floating around. Seems consistent with all arcade collectors on forum or in meetup. It seems on lots of posts or people talking about colour issue responses just "hit it with the rejuvenator", "needs to be rejuv", etc instead of "test it with the analyzer, make sure it's good". Not specifically you guys...but it wouldn't surprise me judging by what you are saying :P.

To me it's similar to a post about a PCB issue and just non stop replies "crank the voltage", "see the little knob on the PSU, turn that" etc.... Hold on... Shouldn't we check it first? Measure what the voltage is and then decide what to do? What if it's already at 6v? What if it's at 5.1V? I mean there is a device (voltmeter) that will easily tell you exactly what it's at and if it's even a problem. Sure you might get lucky and just taking a (poorly) educated guess that turning the 5v knob fix the problem... but at the very least it's bad practice and very bad advice to give. If you measure it and decide to see what happens if you go above normal or whatever then fine, but to say that's the way to go about it is not good imo. People seem to get that concept but not the other for some reason. Just guessing anything regarding electronic measurement is awful practice.

I don't even understand the logic of not wanting to use the meter. In basically every device I can think of its even in the same unit. In a 467/490 (probably others) you literally have to skip over the test function to hit restore function lol. If your meter is no good or inaccurate then - yes obviously repair or replace. Same would apply to any electronic measure device though: voltmeter, ohm meter, esr meter, whatever. The emissions test is an electronic measurement same as the others. It's basic math, there's not a lot of wiggle room for guess work. To say you guys are eyeballing how many microamp the cathode is going to draw on a non running tube is absurd...there's just no way. If you are basing your judgement on how the tube is displaying an image than that is also (semi) wrong... anytime you are displaying an image there are many other chassis components that are also causing variation (pots,caps, etc). It's not an accurate representation of the bare tube health which is what you are trying to test.

I can't guess what the ESR value of a cap is just by looking at it (without a meter).
I can't guess what the 5v rail of a psu is outputting just by looking at it (without a meter).
I can't guess what the emissions level of the green cathode inside a vacuum tube is just by looking at it (without a meter).

Neither can any of you.

Does anyone have a valid reason why they aren't using the meter designed specifically to show them what they are trying to guess? ...other than "sometimes it just works" :P. Out of all the tube I have hooked up I can't think of any time the tube has shown something working (or not working) that the meter hasn't been able to read... emissions, cuts, tracking, shorts, have all been accurate from my experience... There's really no other function of the tube. If your meters are garbage get a new one but don't give bad advice to just not use it.
 
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Honestly, I think you're on point. It's just that past experiences with my meter has shown that I don't agree with everything the meter is trying to tell me. It's possible it's just badly calibrated. Hopefully I'll come across a service manual for it and I'll get to recalibrate the thing.

However, I don't agree with you that you can't spot problems with the tube without an analyzer handing them out for you. Kind of like in your example below:

You have piece of wood with paint on it.

You sand it down to remove paint.

You now have bare wood.

You decide hmmm maybe I should keep sanding it down.

Your wood isn't going to get "more" bare... You will just have less wood.
How do you know you've hit bare wood, do you measure the thickness with a caliper or do you judge it with your eyes? :P

I recently rejuvenated a tube out of a Toshiba PF. All the guns where showing green on the meters, but it had bad focus. What would you have done in this case? Just let it be, because the meters are telling you it's OK?
 
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I recently rejuvenated a tube out of a Toshiba PF. All the guns where showing green on the meters, but it had bad focus. What would you have done in this case? Just let it be, because the meters are telling you it's OK?
oh and did it make improvement on Focus?
 
You are trying to come up with sneaky excuses for not doing things properly lol. The meter *should pick that up.

Probably not put too much thought into wood example it's not complete analogous. Was only meant to show (not sure word...) "Reductive" nature of rejuvenate process on cathode.

I think there is a place for experience and observation. I do not dismiss it. Not everyone has many tubes of experience under them, they don't have many perfectly working chassis and many perfect tube to swap in and troubleshoot by elimination that way, etc. Especially people that don't even know what emissions test/analyzer/rejuvenator are or how they work. Don't let that be excuse for bad practice/advice though.
 
oh and did it make improvement on Focus?
It did yes.

However, I have enough MS9s that I know that if you have the contrast on too high with that chassis, the picture will become a smear. So if a MS9 came to me that looked blurry, I would service the chassis and calibrate the monitor before ever thinking about rejuvenation.
 
oh and did it make improvement on Focus?
It did yes.

However, I have enough MS9s that I know that if you have the contrast on too high with that chassis, the picture will become a smear. So if a MS9 came to me that looked blurry, I would service the chassis and calibrate the monitor before ever thinking about rejuvenation.
Yea. And now we are back to the question what is really the best start point of a calibration.

:)
 
You aren't color grading movies for Hollywood, you're playing video games. You don't need a CRT analyzer. The CPS2 color bar will do just fine. Does it look OK? Great, play some games on the thing.
 
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