I'm playing with a rejuvenator too!

LyonsArcade

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Hi guys;
I just bought a Sencore 161, it's an older one that came out before the 'big mack' series. I was able to wire up an adaptor no problem, but I'm having trouble understanding what's going on.

I've done 4 tubes.

The first one, after setting the heater voltage to 6.3v, and setting the gun balance up, the blue tested low, in the bad area. This machine has a 'bias' setting, which it says low equals 25 volts, normal equals 50v, and high equals 75v. I've been setting it on 'normal', not having the right setting for any of these tubes (I signed up at sencore.com but they haven't answered yet). The manual says this is the grid bias.

When I zapped the blue, I used "r1", they have three. R1 is the regular voltage +15 percent, r2 is +25 percent, and r3 is +35 percent. I've been using only r1 so I don't over do anything. The red and the green both tested 'good' on the meter, and after zapping, the blue tested good as well. Nothing tested with any shorts. I checked the color tracking, and it said it was bad, but all three guns said they were good. Monitor board works great and has been recapped, but still I get a bad picture. Way too dim.

After I put everything back together, the monitor looked about the same, really no better.

Tube #2, was on a U2000. Horribly dim, monitor has already been rebuilt. I tested it, none of the guns said they were 'bad'. I zapped all three with the r1, and when I put it back together, everything looked much brighter. Not perfect, but much better. When I checked the color tracking, it said it was bad. All three guns said they were good, though.

Tube #3, was another U2000 tube. I tested it, none of the guns said they were bad. image looked horrible, though. I zapped all three with the r1, then checked the color tracking. Still said all three guns were good, but the tracking was bad. Put it back together, the image still looked bad.

Tube #4, was a K7000 tube, with no red. I tested it, and the 'red' was in the questionable area. Zapped it with r1, the green, and the blue, and the red fell into the 'bad' area. tested the color tracking, tested bad. Hooked everything back up, and the monitor has a nearly perfect picture now.


So my thing is, what the hell is with the color tracking? I can't get ANY tube to tell me that the color tracking is good, and when the guns are said to be bad, sometimes they look good, and when they say they're good, sometimes they look bad. It's as if the meter is useless and you get the best picture by just zapping each gun with the r1. I haven't tried the r2 or 3 yet.

Anybody have any experience with this model? I have a heathkit coming as well I'm going to experiment with.
 
I'm fixing to head out to do some shopping (yay) so I'll come back an re-read your post and respond better.
But I have a CR161 also and use it quite often, honestly all I have ever needed to use was the "remove shorts" function. But I can explain better how I've used mine later.

Would love to get a scan of that manual though as I don't have one. :)
 
I'll see if I can figure out how to scan it.

When you used the 'remove shorts', did you do it after it said you had a short? None of mine tested with any shorts (according to the rejuvenator), so I didn't use it. I just used the 'r1' function.
 
Sorry, been kind of a crazy week....
Now keep in mind I have NO manual or any documentation whatsoever other than what's in the lid, so I learned by closing my eyes and pushing buttons. (well, not quite that drastic)

I have my BIAS set to Normal, as I have no other documentation to go by so have left it there with no problems so far.

I use the Remove Shorts option regardless of what the short test shows.
I kinda think of it as a lower than R1 rejuve option since I don't have any actual specs to go by.

Set the CR161 unit to Set Filament.
I generally set the heater voltage to around 6.3v especially if the tube is unknown. If you can look up the particular great, set it accordingly. Set the basic voltage and then fine tune with the knob while watching the meter.

You can do the Check Shorts option at this time, but I personally have yet to see one.

Set the unit to Gun Balance and adjust each individual gun, Red, Green, Blue, dead on the gun balance line on the meter.
You want to set the gun balance after it has warmed up a bit, both the CR161 unit and the tube.I usually cycle through and set each gun a couple times until it stabilizes and reads the same as you go through them.

Now switch it to Check Emissions to get an idea what each gun looks like. Cycle through each color and check the meter for each.

While it's on the emissions check the heater will be lit and keeping things warm, switch over to Remove Shorts and quickly hit the Rejuvinate button. Return it back to check emissions and select the next color gun and repeat the warm up for a bit and shoot it process. Do this for each color gun.
You'd be surprised the pop you get from some even though they do not show as shorted. And if one gives you a much bigger pop than others, I'd recommend repeating the remove shorts function for that gun. (blue guns seem to do it to me most often) I generally do each gun twice anyways.

After hitting each gun with the Remove Shorts function, return to the Set Gun Balance and recalibrate each gun and see if there is a change in the Check Emissions function. (should be better, but not worse if all goes well)

I have yet to actually need to do much more than that to get sufficient color and overall brightness improvement.
I played with the Rej1, 2, 3 one time and it seemed almost over kill.
(#3 about made me piss myself)

I hadn't figured out any advantage to the Automatic Tracking yet.

Do you have a CR23 socket for yours ?
I had to make one from an old K4600 neckboard socket. I can give you that information if you need it.
I still need to make up a CR31 adapter though, just hadn't gotten around to it.
 

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one thing i appreciated about the Heathkit was that i could easily follow the directions in the lid without assistance or other instructions. it wasn't all that difficult to do my first tube and that turned out great.
 
Kevin, thanks for your help. I played around with it a bit again yesterday; on one tube that didn't seem to make a difference the first time I zapped it, I hit it with the r2 on each gun, even though they all tested 'good' . The improvement was drastic after that. I still haven't used the fix shorts, but I will next tube. Thank you for the step by step, that's kind of what I was doing but not with the remove shorts button. I've noticed that after you hit the r1 on it, you can readjust the gun balance but I never get the tracking thing to work either. I'll reply back after I use the 'remove shorts' function.

MC3OO, I bought a heathkit but it got busted into a million pieces in the mail. I have everything back together except the heater meter, I have to figure out how that wires up... I have a grey wire and a resistor that apparently connect to it but don't know where! Since it's a meter, I suppose it probably doesn't matter.

I did build a CR23 adapter for the Sencore, I think to do a 31 I could probably just jumper wires off of it to the new socket, right?
 
your Heathkit didn't come with the build instruction manual or the illustration packet? those would both be invaluable in putting it back together, i would think. unfortunately the rights to all Heathkit documentation were purchased by a vendor at some point, and that vendor keeps illegal copies from being posted for download.
 
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