WG 6100 repair logs

[level42]

Let me say it this way: If that WG6100 would have to stay in one of my games, I would throw this in the dustbin now and order a new LV2000.

I _MIGHT_ be able to get it better redoing ALL solderings, fixing the tracks with wire, replacing the cut-off parts so they have long leads, but I would still not be 100% sure about it...and it will stay a mess one way or the other.......and I don't like that.....I don't want it to die anymore......I don't want fires in my precious cab......

Anyway, choice is up to you Béla....if Franck still wants his LV2000 light I can order another one for you but it wil of course take some time to get here....

[Belike]

 
Wtf is that black slime on my LV 2000?
You are right André, even a noob like me would solder it better.
I would gladly buy that one from Franck, but I will also place an order for other parts to Arcadeshop.com this week, I can also order some from them.

[level42]

So....I could use the one I have here and you could order a LV2000 lite from AS and then send that one to Franck (or if he has time enough bring it to Eurocade)..... ?

I do think the one on Franck's is OK.

Franck ?

[atarimania]

Yes you can!!!! 

(Sorry for the delay of my answer, not a lot of time for arcade for the moment )

[Belike]

Thanks Franck.

[level42]

Brilliant guys, but hold your horses with ordering a new LV2000....

I sent the pics and the story to Jeff Hendrix who makes and sells the LV2000 and he offered a new one if I would ship it back !!!!!

So I took that offer naturally.

Anyway, I think Jeff deserves a fair bit of free advertising for this EXCELLENT service:

For all your WG6100 power supply problems, get a LV2000



or LV2000 lite:



http://www.vector-repair.com

....or at your favorite arcade parts dealer



I mean, this is hardly his fault...yet he still offers to replace it. I am not the buyer, nor is Béla directly and still this great service.

IMHO this is the kind of stuff that makes you a returning customer !  

[Belike]

Sounds great and I really appreciate that you asked him.
This kind of customer service is quite rare these days.

[Etienne MacGyver]

Thats the way i like to do buniness!

Very nice gesture of him. 

[level42]

Back on these...

I had a very "enlarged" picture with one of the deflection boards, something that usually is called "blooming". This means everything is too large on the screen. The cause is a low High Voltage, and thus a low B+. I measured it and indeed it was only 150V. Probably because I replaced the pot on the HV board, I can't even remember 

Anyway, adjusted the pot and got the supposed voltage of 181V and focus and size of screen were normal again.

Now, I was missing the red color and the overall picture still looks not perfect yet, just not what it is supposed to be.

Removed the neck board and checked all the parts in the Red amplifier circuit, everything seems OK. I cleaned the pots (for now) and redid ALL the solderings on the board. Some of the wires that run directly to the board were still "hanging on" with just one or two strands, so I removed the "pins" to which they are soldered to the board and instead soldered them directly.

Now I'll have to test again....tomorrow...

[Belike]

Thanks for the update.

[level42]

Pffff.....did I mention I really am not too fond of WG6100s ?  

I completely resoldered everything on the neck-board. Hooked it up today and saw......nothing.

Turned op the Screen pot on the HVT and there is picture (the wrong way, with the bright spot in the middle, but at least deflection is running OK.
Spot killer LED is on though.
Check B+ again: 27 Volts......huh ?!?!

Tried adjusting the HV board pot, no change at all.

Oh no here we go again, removing the HV cage... checked transistors =>  OK, checked resistors => OK checked the Pot => OK.
Can't locate my ESR meter at the moment to check the caps......where did I leave it .....?
Someone on KLOV forum suggested ZD902 might be bad even though it tests OK in diode test. Could well be....will put it back in and see what voltages come out of it, should be something like 150V

When I hook up the other board I have absolutely no deflection at all.....well sometimes the Horizontal works.....

Worst thing is tomorrow and wednesday we have extra rehearsals....hopefully thursday to be continued....

[Belike]

Thanks for the update.

+1

[level42]

Yeah, the sad thing is that I seem to be going two steps back instead of one step forward each time I work on them...I want these done and back to you guys, won't be doing anything else in the hobby before I can send them back, hopefully fixed !!!

[level42]

Found the ESR meter again yesterday. Checked all caps, all seem OK, one shows a "R only" at 2,2 Ohms but this may be caused by a 2,2 Ohms resistor that is in parallel with the cap, will have to desolder the cap to check it out of circuit
(C914).

I have a hunch that ZD902 may be bet even though it measures OK, the FAQ also points into this direction.

Going to have a look if I still have a cap-kit because I think it might be included and I also want to replace the pot...

[level42]

I barely dare to add to this thread anymore but.....ok here goes:

I got a fully repaired 6100 here now (from Thwocker's Tempest) and this is great so I can do some comparing steps instead of "flying blind".

Working on one Atarimania's deflection boards now and I first discovered the weirdest thing ever. I was going through all the transistors again , checking them for shorts. I wasn't getting any shorts but because I was now comparing the values between the good working deflection board and the "bad" one's, I suddenly had some different values on Q800 and Q801. To my amazement, there were NO shorts BUT the transistors showed the values "the other way around" ! This meant that they were PNP transistors instead of NPN's !!!
I checked the markings on them and looked up the datasheet and sure enough I was right !



These two transistors are in the spot killer circuit and I guess as long as there is no need for the spot killer to become activated, this wasn't much of a problem for the board to work. However, if such a situation would arise, the spot killer would for sure have failed and burned a nice hole into the tube (maybe that's why Atarimania's tube has such bad burns in the center ?)

Now...when I looked further both Q801 and Q802 had the same partnr. as Q800.....and the markings looked EXACTLY the same.
Also: I looked at the solderings, and they looked EXACTLY as dull (and as poorly soldered) as all the others on the board !!!

My conclusion: someone royally screwed up in the factory and grabbed the wrong transistors for Q801 and Q802 !!! It was just never noticed. Seeing the general quality of Wells Gardner (and it's obvious poor quality check system) I am actually not that much surprised at all !

The thing is: normally I just go over the board with the DVM in diode check setting, not caring much about NPN or PNP because you expect these to be correct, just focusing on shorts on transistors. Without the matching board to compare I would never have noticed !!! ANOTHER LESSON LEARNED, NEVER expect things to be as you expect them to be.


OK....so I replaced both transistors with the correct one's  (2N3906 out, 2N3904 in)and tried it on the otherwise 100% working monitor.

Got picture, but....not entirely perfect. It looked like this when just started up:



However, the longer it was running, the more of the missing lines appeared....until I got almost a full picture (had to leave for a while then).

I need some freeze spray

The really weird thing is that the vertical lines are mostly fine.....but the horizontals are missing..... any way, it seems to be temperature related...and it is also on all colors exactly the same...