Polo fixed, but now the yoke is bad?

mecha

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this is lengthy, because I feel the need to share every little detail.

here's where I'm at. some few months ago or so I posted about a Polo that blows fuses. well I find out that little transistor on the heatsink in the power supply was the cause. I capped the monitor properly (some asshole before me had some caps installed backwards) and touched up a variety of other things.

during my quest to fix the power supply cause of the blown fuses, I borrowed a few parts from an extra 27" chassis I had. one of those being the T101, which is what stopped the fuses from blowing. I put a HOT that I thought was good in there, and well, it wasn't, it just ticked.

going based on Fromm's flowchart, I tested all the diodes and the the block caps by the HOT, and that was all fine. put the old HOT back in, the chassis actually works.

except one thing... it does this and emits an obnoxious buzzing sound.

315531_10100290700146679_30804676_47106715_1671484266_n.jpg


this is not the original chassis for this monitor, the first one was one that got sent to PNL and Chad for 3 different repairs. I never got around to sending it back to Chad again. when it blew the HOT again after he fixed it, I called him about it and he suspected that maybe I had a bad yoke that could be causing it. this is the first time I've mated a working chassis to this tube since late 2009 however, and it never did anything strange before, soooooo...

how do I go about testing to make sure the yoke is fine? or could this be something where I dicked with something at the yoke plug on the chassis on accident? I checked over my work multiple times and nothing stuck out after the few little corrections I made.

would any of the power supply components I changed make a difference? I actually took a picture of what I changed after I capped it.

310975_10100287626975339_30804676_47095954_1534216820_n.jpg
 
shorted yoke? yeah?

what does this mean...

orange/yellow: 2.2 ohms
red/brown: 6.5 ohms

according to http://www.junknet.net/donor-tvs the readings should be 1.7 and 5.7 ohms respectively. does this solve the riddle of this god damn tube?

EDIT: holy fucking shit. I went to compare yoke readings to my KI2 and observed something I read in another thread at arcadecontrols about the replacement flybacks... I think I have the focus and G2 wires switched. oh shit.

EDIT #2: I have vertical height adjustment, vertical deflection works. no horizontal deflection.
 
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in my experience, a buzzing sound and that picture = hv leakage/arcing somewhere...

aall ive ever seen cause it was a flyback or arcing at the anode cap...

id fire it up with the lights off to make sure you dont see any arcing.

you did remember to reconnect the tube ground right?

glad to hear those old chassis of mine finally came in handy for parts.
 
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Switched the focus and G2 wires to where they need to be. Gah! Unfortunately I only have a vertical line now. I'm leaning towards me installing one of the block caps wrong over by the HOT (in tech terms, I think that just means there's no return for the horizontal deflection, since I do have high voltage...?) Watched some randy fromm last night, I have a better understanding of how deflection works now, I think lol.

Ill see if I can pull another miracle out of my ass later. Id try a working chassis with this tube, but the last time I tried that with a K7000 I rebuilt, the chassis that was already working in it took a shit in transit.
 
dear KLOV,

I'm an idiot.

love,
mecha

no really, when I was testing the block caps in the horizontal section, I installed the one that comes off the yoke header in the wrong spot. lol

I pulled my KI2 Polo to test on this tube and I had horizontal deflection. as per what I watched about yoke returns in Fromm's video, I saw that uh... yeah, whatever. I fixed it.

mecha: 3 Polos: 0
 
No worries brother... iv done some dumb stuff like that in my time aswell. Atleast its working now. Was fun, no ? ;-p
 
I actually referenced your thread over at arcadecontrols for some shit. it may have been there that I saw the one guy talking about the replacement flybacks having different colored wires, and that's when the G2/focus thing dawned on me.

nonetheless, I have a few things I can say about Polos now. one day I need to source all the transistors and replace them on all my Polos. CEC_DFW had a thread with all the parts listed, in case you needed them at all.
 
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