Another rejuvenator Q - what have I done wrong?

petieken

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I recently acquired a BK467 rejuvenator, I have an old vga monitor (LG tube) that suited fine for the first test. Blue & red were ok (green zone) but green was pretty weak (yellow zone). I tried the clean/balance option (push green button and let the needle drop to the red zone according to manual), now the green is way down into the red zone. When setting G2 I now need to set switch it to high setting to get the needle moving.
I connected to monitor again to a computer and there is NO green anymore...

What have I done wrong?
 
It sounds like the green gun finally gave out. I don't know if it was on it's last leg and finally died or something in your set-up was performed incorrectly but, since you state that the green gun was already low I assume it was almost dead and the attempt at rejuvenation finished it off. This is always a possibility with a tube that has a weak gun.
 
I recently acquired a BK467 rejuvenator, I have an old vga monitor (LG tube) that suited fine for the first test. Blue & red were ok (green zone) but green was pretty weak (yellow zone). I tried the clean/balance option (push green button and let the needle drop to the red zone according to manual), now the green is way down into the red zone. When setting G2 I now need to set switch it to high setting to get the needle moving.
I connected to monitor again to a computer and there is NO green anymore...

What have I done wrong?

Have your tried cleaning the gun more than once. Manual says it might take a few shots to work
 
Yes I did, and like the manual says, switched over from clean/balance to rejuvenate after 2 times. But no luck, needle stays very low. I did see a little green when entering the service menu on the monitor and cranking te cutoff to max value.
 
with it on try rapidly tapping on the neck of the tube where the guns are..

sounds crazy but its krap anyways right? you may have had the g2 voltage or heater voltage set incorrectly. if either is too high you can smoke the guns immeadiately.

was the tube discharged when you did the rejuve?
 
with it on try rapidly tapping on the neck of the tube where the guns are..

sounds crazy but its krap anyways right? you may have had the g2 voltage or heater voltage set incorrectly. if either is too high you can smoke the guns immeadiately.

was the tube discharged when you did the rejuve?

Yes the tube was only to do my first test with the BK467.

Heater voltage was set to 6.3V according to the manual for this tube. G2 until the needle moves 1 division. Right?

The tube was indeed discharged, and I laid it on a towel with the screen down to connect the CR-socket and all the tests/rejuve.
 
i've got the same unit - i think its the clean balance setting that makes the heater voltage go up just a tad. Set it to that setting, and let it heat up a few minutes, then gently tap the side of the neck with the handle of a screwdriver. This may very well clean some crap and allow it to work again.
Sometimes, there just is no rejuving a dead gun, but, sometimes it takes several rejuves to get a gun back. Won't hurt to tap it with the screwdriver handle while rejuving it as well. Keep at that green gun - you've got nothing to lose, you may eventually get it back. They definitely take a little getting used to before you get good with them.
Fwiw, too, i've yet to remove a monitor from the chassis when i rejuve it - i normally just discharge it, and rejuve it right in the cab. A barstool works perfect to set the 467 on. Plug it in and go. Any time i rebuild a monitor, i put the rejuve on the tube just to see where it's at. More times than not at least one of the guns is a bit on the weak side, and a quick rejuve brings it back into spec.
 
Any time i rebuild a monitor, i put the rejuve on the tube just to see where it's at. More times than not at least one of the guns is a bit on the weak side, and a quick rejuve brings it back into spec.

Thanks for the info.
When you say rejuve, do you mean you use the rejuvenate setting from the first time or clean/balance setting first?
 
neither. i just test the output of the guns, and the color tracking. If any are low, i clean and balance and recheck, then rejuvenate as necessary.
 
Ok, thanks for all the info. I'm soon going to test 2 WG K7000 monitors from the Sagaia cabinet I acquired a few days ago. IF I have to rejuve I hope everything works out better than with the vga monitor :)
 
Does your model have a REJUVENATE option? If so, try that on the green gun. I've only ever used a Sencore and the model I've used doesn't have a "CLEAN" option, but rather 3 settings for REJUVENATE.
 
Yes, there are 2 options: "CLEAN/BALANCE" & "REJUVENATE" after 3 failed attempts at clean/balance I switched to rejuvenate. Had a few goes there, but still nothing.
 
Can anybody point me to a location where I can download the service manual for the BK467? I have lots of free time this week so I'm going to reflow the solder joints and maybe recalibrate (that's why I need the service manual) this tester if necessary.

Thanks.
 
I already checked the heater voltage according the manual: on the tester 6.3V on my DMM: 6.7V

Could this be the problem for the busted green? Heater voltage too high?
 
The heater voltage should be measured with a "true RMS" type of multimeter to get an accurate reading.

The "tracking range" calibration is more what you need to do.

Remember, on B & K rejuvenators there are two levels of rejuvenation. The "Clean & Balance" and "Rejuvenate" switch controls it. "Clean & Balance" is the weaker of the two functions and should be used first. You should not hold down the red, green, or blue pushbuttons longer than 15 seconds or you could damage the tube. When switching the rotary switch to the "Restore" position, allow 60 seconds for the rejuvenator to build up a proper rejuvenating charge.
 
Ok, thanks for all the tips. I know to use clean & balance first, I followed the instructions this way.

I started the tracking range calibration:
-100K resistor between 'Red K' & 'Blue G2'
-Set 'normal'/'high' to normal
-Set to TEST
-Turn Red G2 until dial reads 2.0 on upper scale (full scale)
-Adjust R23 for minimum reading by pushing TRACKING button.
Here's a question, is the needle supposed to drop to 0?
I adjusted R23 but it only drops to 0.45 on the upper scale... Turning the trimmer further does nothing.

I noticed this when I did my first test, the needles are constantly shaking slightly when testing a tube, the needle did this now too when calibrating the tracking range. Is this normal, or is there a failure?


Again, thanks for all the help you guys gave me already, I learned a lot in the past few days. :)
 
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