Convergence Strip Tips

For monitor related issues
Post Reply
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Convergence Strip Tips

Post by kuze »

I was wondering if you folks have any tips for using convergence strips.

Let's say I have a rather major convergence issue in the upper left portion of the screen. Is there any rule of thumb for where a convergence strip will be most effective? How many are generally needed to fix one corner?

Should I start by adding one from that direction towards the yoke?

As long as I do not touch the anode cup, I shouldn't be electrocuted if I accidentally touch the back of the tube and/or yoke while it's on right?
User avatar
yosai
Windy City
Posts: 4057
Joined: August 17th, 2008, 5:00 pm
Location: London
eBay: yosai

Re: Convergence Strip Tips

Post by yosai »

Post a pic before you start. If it's bad you probably want to adjust the purity rings.
User avatar
PrincessPrinPrin
Posts: 577
Joined: April 7th, 2011, 4:00 pm
Location: Pordenone, Italy
eBay: *mkl*
Initials: MKL

Re: Convergence Strip Tips

Post by PrincessPrinPrin »

Yes, post a pic (a grid, not a game). Strips don't do miracles, they have a minimal effect. If it's a flat tube there are dynamic convergence adjustments on the yoke. As for shocks, if the tabs where the horizontal yoke wires are soldered to are exposed (not insulated) stay away from them (1000V there).
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Re: Convergence Strip Tips

Post by kuze »

Thanks guys. It definitely seems within the realm of something convergence strips could fix, at least from what I've seen on Youtube.

Let me know your thoughts:

Image

Image

It's an MS2930 monitor if that makes any difference. 8-)
User avatar
Shadolf
Posts: 287
Joined: November 6th, 2014, 12:20 pm
Location: South Germany
eBay: 1984indigo

Re: Convergence Strip Tips

Post by Shadolf »

That looks like a case for strips, indeed. It's not that hard or complicated as long as one needs just one or two per corner. The problem is with a 29" in a cab you need to be two persons or use a mirror. I use always a rubber glove and I try to leave my left hand in my pocket all the time.

I have also a problem a little like this with a Sony Trinitron, but in this case had no luck with convergence strips and/or corner convergence tabs. When I have time I should make a thread.
User avatar
DaveyD
Posts: 344
Joined: December 9th, 2014, 7:14 am
Location: Grimsby, UK
eBay: Dr_Daph
Initials: DPD

Re: Convergence Strip Tips

Post by DaveyD »

I've had a 19" monitor worth convergence like that in the bottom left corner. Made some convergence strips myself and fitted them. Looked quite good afterwards
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Convergence Strip Tips

Post by grantspain »

yes looks like two should do the job just fine
User avatar
NoAffinity
Posts: 386
Joined: January 8th, 2017, 3:46 pm
Location: Escondido, CA, USA
eBay: noaffinity
Initials: CSG
Contact:

Re: Convergence Strip Tips

Post by NoAffinity »

I would suggest starting with re-adjusting the existing strip (assuming there is only one currently) in that corner. If that doesn't get you where you need to be, then adding a strip would be your next step.

I always where nitrile gloves when working on electronics. I forget the mil size, I get a box of 100 for like $10 at the electronics store. A) It keeps grime, electronics dust, and other things off my skin - who knows what health hazards that 20-30 year old matter poses if absorbed through the skin, accidentally rubbed into various places, etc., and B) reduces shock hazard. Not that B should preempt a healthy abundance of caution being taken when working on a live monitor, but it's an added layer of protection.
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Re: Convergence Strip Tips

Post by kuze »

Thanks guys. Do you think it will be possible to add the strips via the maintenance hatch on the Blast City? Or am I absolutely required to pull the monitor out again to do this?

I don't really have anyone to help me pull the monitor, so I'd rather leave it in if that's even doable.
User avatar
nem
Needs a custom rank
Posts: 2768
Joined: August 17th, 2008, 6:59 pm
Location: Finland

Re: Convergence Strip Tips

Post by nem »

Trying to do it through the maintenance hatch sounds like a recipe for disaster. I wouldn't try it.
User avatar
rewrite
Posts: 203
Joined: April 30th, 2014, 4:11 am
Location: California, USA
eBay: quin-leyd
Initials: ATP

Re: Convergence Strip Tips

Post by rewrite »

nem wrote:Trying to do it through the maintenance hatch sounds like a recipe for disaster. I wouldn't try it.
Seconded. Just put the cab on its back, and pull the monitor up. Way easier than trying to get it out over the CP. It's easy not hard, for one person :) .
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Re: Convergence Strip Tips

Post by kuze »

Going to give this a go on Thursday with the help of a local CRT expert. Wish me luck! I'll post back with some after pics once the work is done.

The back of the monitor and the chassis is also very dusty. Should I hit it with a can of compressed air while we work on it?

He is going to bring over a rejuvenator as well and we might give that a go on the tube. I've also got a spare MS2933 chassis that could be installed in place of the 2930. Do you guys think that going ahead and doing a rejuvenation and chassis swap is advisable? The autosync feature of the 2933 and OSD service level adjustments are appealing and from what I was told by the seller it's a NOS chassis. On the other hand the existing chassis is mostly calibrated except for focus and the corner convergence issue.

I believe the heater resistor on the 2933 chassis would have to be swapped out for use on a 2930 tube, but I've got the correct replacement (2.2ohm) that grendelrt used with great results.
User avatar
cools
Armed Police Buttrider
Posts: 13457
Joined: August 17th, 2008, 4:49 pm
Location: Wales, United Kingdom
eBay: hordarian
Initials: CLS

Re: Convergence Strip Tips

Post by cools »

The picture is great. Give the tube a clean, fix the corner, leave it alone until it breaks.
Image
User avatar
Rossyra
Supermod
Posts: 7902
Joined: February 12th, 2009, 1:24 am
Location: UK

Re: Convergence Strip Tips

Post by Rossyra »

Yeah, I agree, no need for a rejuvenator.
Image
User avatar
NoAffinity
Posts: 386
Joined: January 8th, 2017, 3:46 pm
Location: Escondido, CA, USA
eBay: noaffinity
Initials: CSG
Contact:

Re: Convergence Strip Tips

Post by NoAffinity »

Third'ing the sentiment here - do NOT rejuve it. Rejuve is good for restoring a tube that is suffering from dull colors, after a cap kit and any other efforts have not produced the desired result. But, there are also risks with rejuvination - the worst of which is you kill the tube. In your case, the colors look great, don't risk killing the tube needlessly.
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Re: Convergence Strip Tips

Post by kuze »

Thanks again guys! Will pass on the rejuve, fix that corner and adjust the focus a bit then I should be in great shape!

Will post back with the results tomorrow.
kuze
Posts: 99
Joined: September 29th, 2013, 5:09 pm
Location:

Re: Convergence Strip Tips

Post by kuze »

Good news! We got the convergence looking much better, as well as the focus perfectly tuned and I'm quite happy with the results.

Image
User avatar
NoAffinity
Posts: 386
Joined: January 8th, 2017, 3:46 pm
Location: Escondido, CA, USA
eBay: noaffinity
Initials: CSG
Contact:

Re: Convergence Strip Tips

Post by NoAffinity »

Looks great! :) :thumbup:
Post Reply