CurtPalme.com Home Theater Forum

**Curt Palme**

So this is kinda cool! I've got 3 flaky red Barco 1209s tubes here that don't go to black. They flicker, and one has retrace lines in the blacks.

I had to pull the tube out to put in another one as I sold the 1209s, but before I did, I decided to try and zap the contamination out of it with my Sencore 7000. I had a crapload of old Barco 800 CRT sockets/PC boards lying around, so I put pigtails onto one of them (after realizing that the pinout of a LUG tube is different from an 800 tube, DOH!)

So I finally read the Sencore book ( Mr. Green

) and did the ''remove G1 short' from the tube process. The damn thing worked! Perfect blacks, no flickering! Finally my Sencore pays off!

I'm about to yank that tube out and put in the REALLY bad one, that has a massive dot in the middle of the tube at turnoff, retrace lines, and flickering. Interesting that the tube I just did and the one I'm about to do had 2400 and 3200 hours on them respectively. Wish me luck.... will report back in a bit.

CIR Engineering · Posted: Tue Jul 09, 2013 7:36 pm Post subject:

I'm really happy with the CR7000, it can work wonders. Be sure to read towards the end of the manual where they talk about dynamic shorts and how to fix them. Dynamic shorts are the type that only manifest when the tube gets warmed up and are intermittent. Sencore suggests running the heater voltage 50% above normal to get the tube hot and hopefully cause the short to show up on the CR7000. I have tried it on three tubes and the technique really works Smile

craigr

**Curt Palme** · Posted: Tue Jul 09, 2013 7:54 pm Post subject:

Well, nada on the second tube with really bad flickering and the fireworks at shutdown. Tried G1 short and rejuvenation, but no go. I can try the elevated heater, but I've gotta wrap this set up, so I'll try once I have another Barco on the bench.

CIR Engineering · Posted: Tue Jul 09, 2013 9:23 pm Post subject:

Well, if you have a short to the heater as you know you can't fix it. The heater at 150% just produces more heat so that the traces deflect faster to reproduce an intermittent short.

craigr

stridsvognen · Guest

Ohh so now i need to find a old CR7000, and see if it will save my 800 hour 9" Panasonic tube, and 8" green from my Marquee machines.

The 8" green tube have like a flare visible when dark, still not anoying for normal use, but my 9" blue tube just went crazy and got bright, and what i guess is the spot protection kicking in when turning it off. Crying or Very sad

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

Yes, as discussed with you Curt, my blue P19LUG is doing that.

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

There is no short that cannot be breaken, it's just matter of amperes Mr. Green

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

What does a Sencore 7000 cost?

barclay66 · Posted: Wed Jul 10, 2013 6:53 am Post subject:

stridsvognen · Guest

That looks like some old solid German gear you got there..

You had any luck saving some marquee tubes with that one.?

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

Youll have to translate and label the controls for him!! Laughing

stridsvognen · Guest

barclay66 · Posted: Wed Jul 10, 2013 9:35 am Post subject:

Hi,

Until now I have been lucky. None of the tubes I have show any symptoms of grid shorts. I have used a newer version of this device (BMR 95) in order to determine the emission curves (G1 voltage vs. beam current). This gives You a first idea of the tube's linearity (phosphor characteristics is another factor of course) and of the tube's system wear...

Edit: The usage of the BMR 7 is quite straight forward. I could talk You through it as soon as You have it.

Regards,
barclay66

**Curt Palme** · Posted: Wed Jul 10, 2013 1:06 pm Post subject:

Ummm, excuse me, I actually spoke German before I spoke English. I remember struggling in kindergarten with some English words. Smile

Now, like the limited Cantonese I speak, all I remember is the swear words. Razz

I can actually fake it in German still, nothing that a month in Germany wouldn't cure...

Tinman · Posted: Thu Jul 11, 2013 5:55 pm Post subject:

I have both a CR-70 and a CR-7000. When I started working on trinitron tubes, the 7000 was a must. A CR-70 is too powerful for them.

It's amazing what the CR-7000 can do in the right hands. Sometimes you have to improvise a little to get dynamic shorts out, but you have nothing to loose at that point. The CR-7000 has made me good money in service.

BGSPCS · Joined: 23 Aug 2006 Posts: 115 Location: Pottstown, PA

Curt, did you try doing the short repair on the red tube I sent back from the Zenith 1200x? I'd be curious to hear if you were able to clear that up.

**Curt Palme** · Posted: Mon Jul 15, 2013 3:52 am Post subject:

No, not yet. It's sitting here though, and next time I have a Barco on the bench, I'll try it. I also realized I have a CRT tester from VDC here that Tim gave to me earlier this year. I'll try and see if it sees the difference between a working and a partially shorted/contaminated tube...

Motobias · Posted: Fri Aug 30, 2013 7:00 pm Post subject:

@curt falls du mal nach deutschland kommst, sag bescheit - ich schulde dir mindestens ein bier Smile

translates to

in case you are coming to germany, let me know - i owe you at least one beer Smile

**Curt Palme** · Posted: Fri Aug 30, 2013 8:04 pm Post subject:

I understood it the first time. Smile

(barely).

I am actually renewing my passport as we speak, first time since it expired in 1986, bu no plans to leave the continent.. yet..