when i turn the Sencore on the needle moves a tad, but goes to the start of the red (Bad), needle doesn't move at all after nor does it when adjusting the cutoff control

Are you sure you have the tester hooked up right, with the knobs set correctly? I fought the UA first time I used it, trust me if you don't pay attention you'll screw something up.

thats the last thing i would do unless you give the say to.. I know how the urges are, urges can cause damage

couple other things to check out with the CR-70, check the pins on the socket that the adapters plug into on the connector coming from the tester. I had one that had a bent pin, so when I attached the connector it was not realla hooked up. Those pins are thin and can get bent.

miniman82 I had the settings the way the CRT chart says at first, than Dave said that's not the correct way, you have to go what the manual says with the U Adapter. So the setting were going by the CRT chart said (Wrong Way) at first, at that time it did not do anything to the CRT.

I have found that a "bad" tested B&W can ofter produce a pic, not great but good enough to at least trouble shoot the set. Then when you get a backup CRT that is good, thats when you give the rejuv a try. I have used the CR-70 rejuv and had good luck with it, but again why mess with it until you at least know how the CRT looks in operation BEFORE trying to improve it.

Same with Color CRT, even a weak gun is not the end of the world, you can do a lot with the bias and gain adjustments to get a decent pic. Back when you could just get a new CRT then fine rejuv, but now I take a much less agressive approach.

Dave some of those pins i notice don't hook all the way around the pins on the CRT, so that could be the problem there

yea you should be sure the pins are clean and you are getting a good connection on the CRT.

I was talking about the connector that the adapter hooks to the tester with, its a small plug with a lot of small pins. just make sure none of them are bent so when you attach, they will be connecting.

oh ok, gotcha... yup the cut off is below the bad levels still, sometimes when i turn it on the needle moves enough to touch the red

Comes to find out the plastic neck was twisted by someone before causing the tube to short out, so now im on the hunt for a 12LP4..Anyone have one? I checked Ebay and looked on goggle, nothing comes up for sale..

Sometime the wires inside the pins come unsoldered and reheating the pins with a soldering iron and applying a little dab of solder will fix it.

If it's been twisted and shorted it can be fixed as long as none of the wires have been broken off flush with the glass, even then it's sometime possible to make a repair.

Just keep an eye open. One'll show up.

I think i would have to get the plastic piece that the pins come out of off, i think some are broken off, but i can't really tell, unless some how i can get that off the neck to where i can see whats coming out of the glass, to see what i can re solder...

I recommend you leave it be, after you get the set recapped and all seems to be working, if nothing on the CRT, then check the anode for HV, and the other pins for correct voltages. If still nothing then you have little to lose by messing with it. I would start with the heating of the pins and some solder on the end of the pins (it should wick in). the more you mess with the base the more likely something will break, pretty much the way it is with all 60 year old parts.

Dave, I've tried that..

I did the cut off test and emissions test again last night about an hour after the first tests, with out any attempt to rejuv, while doing the cut off and emission tests again the tube went completely out and the Sencore stopped making the whistle sound of it firing up the tube. So my guess is the tube was either very week to begin with or one or more connections behind the pins are loose or not making anykind of contact, so basically i have nothing to loose with the tube now..

So now i have two choices.. Attempt to fix this one or buy a good one, and just have My friend restore the TV with a good tube that i would purchase..

maybe it went to air and the filament burned out, I dont recall that tube but can you see the getter (looks like silver deposited on the side of the neck), if its white then you are done, check the 1and12 pins for continuity, should be a few ohms max. Guess you dont have a test CRT for the set (they are small crts that self focus and just used for testing).

I just looked and i don't see any white or anything that looks to be burned out.. I took two pics, so maybe they would explain anything better. I dont own anyother testing Equip other than the Sencore

That's almost a guaranteed disaster to plug in cold-turkey. Likely no serious damage, as long as the power transformer didn't get left on long enough to burn up. That would take several minutes, and you'd probably have blown the house circuit breaker. You probably lost a few capacitors and the 5U4 tube, along with a B+ resistor or two.

Definitely the set needs to be completely re-capped, and then troubleshot-repaired as needed.

Charles

Whistle sound? That's not good. Perhaps the CRT is gassy and the noise is from a discharge. Or, the Sencore is faulty, or you had it hooked up wrong. Or there were still some shorted leads because of the twisted cap.

My CR-70 has never whistled.

John

My Sencore has always made the little noise when it starts up, has done it on all tvs i tested it with. I don't know if its a whistle noise, it just makes a little noise, just dont know what to call it, or how to explain the noise.. I bought it off Ebay about six months ago. I thought the little noise from the Sencore is normal, it seems to perform tests fine, unless it's giving me incorrect read outs i don't know about.

How would i fix the shorted leads? or get the cap off to wire/solder the leads or to check to see if they are not broken?

pretty sure it uses a switching power supply for the filament, that is what you are hearing, mine does it to, its pretty hi pitch, I would guess in the 10-12khz range.

You might find this thread useful: http://www.videokarma.org/showthread.php?t=248393

I kinda figured it was a normal noise.. Did you see the pictures, any suggestions? there's a company in south Carolina that rebuilds CRTs, and that hawk eye guy is retired.. I don't know how much the cost is to ship rebuild and ship back..

Or is there a way to get behind the socket cap to check the leads? I downloaded a file off the internet thats a schematic for that tube..

Ok, interesting looks like that cap comes off in two pieces with pins under the first part.. Thats where i need to get to, and it looks like a task and it's self

I may just get it rebuilt. I tried hawkeyepicturetube.com he's retiring and doesn't want to rebuild anymore, but is looking into another source for that one

and now im trying wmicronics.com they have to get back to me..

I don't how expensive it is to have it rebuilt or get a rebuilt one from any of these guys.. If it's too much, than i will forget about that..

The cap should come off as one piece, unless it's broken of course.

If it's already loose you should be able to heat the pins with a hot soldering iron, one at a time while gently pulling it on teh side where you are heating it, a little at a time.

if you have a really hot iron 25 watts or better you can probably heat two pins at a time but just be very gentle not to break any of the wires or snap off the fragile Glass nipple that's underneath it.

To check for a white getter you will have to remove the tube from the chassis, it'll be in the area under the Yoke.
Some tubes have a Getter near the high voltage connection on the side of the tubes bell, if you can see a white patch there the tube's done.

If you remove the tube use extreme care not to rip the cap off as it goes through the Yoke, they can be tight sometimes, a little heat from a hair dryer or heat gun can help it go through but don't hit the tube with the heat gun or you could shock it and cause it to break.

When I repaired the tube base on my set I used a very small butane torch. I was able to quickly heat all the pin ends and pull the base off. I also used the torch when I re-soldered it.

-J

I will have to try that tomorrow when i have spare time.. I'll report back..Thanks for the info..

Well i actually went ahead and did it, using a de solderer that has a pump to suck out the solder, did it slowly as the cap pulled off little by little, well all the connections are there and none broken.. plus i notice the phosphor on the tube front is coming off as i can see a solid circle in the middle of the tube where light is coming through from the lamp i have in back of the set.. So i guess this Tube is DEAD..

Not nessasarily... could be just a phosphor burn on the face...

Hum maybe, i had my clip on lamp facing right at the neck as i pulled off the black cap, only time i noticed it, i pointed the lamp slightly at a different angle and its not noticeable any more.. Well all the wires that went into the soldered pins, look to be fine, so what should i do next?

test it again this time clipping on to the wires.

I thought that may be the next thing, just wanted to make sure.. I'll report back Tomorrow....

Good luck. Be very careful not to stress those wires with the weight of the Sencore UA clips and cable.

You might want to check out this old thread(s) about wmicronics:

http://www.videokarma.org/showthread...ight=micronics

jr

I guess i won't be shipping to them i guess..


UPDATE: I tested with hooking to the leads with the cap off, and same thing, The filament of the picture tube does not light up, nor does the Sencore make the noise like it's giving the tube juice.. So i guess Dead Tube..

That's weird that it was lighting up somewhat earlier. Have you tested another tube on the Sencore recently, to confirm that it's still working correctly? Have you taken a resistance reading across the filament pins?

Kevin

I tested another tube with the Sencore, and it worked with that one.. I have no other test equipment.. My guess is that the filament inside the tube was week and would have probably blown once the chassis was recapped and powered up the tube.. I looked inside the tube neck and i don't see anywhere that anything shorted out

and did you test the filament wires for continuity?

How would i do that?