G05-802 - think I should reflow my headers?

Nightbringer

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Just kidding, of course I should. I have no idea if this monitor will work after this, but it's the second one I've seen where the P500 socket pulled right out of the board. It's really not a joke that these things were all soldered on by monkeys!
 
Header popped right off when I pulled the cable. I reflowed and did a cap kit on it while I had it out, but it still doesn't work. Oh well, I need to poke around with the DMM tomorrow and see why I don't have HV.
 
nah bruv it looks good, that header is "modular" and all your solderjoints should look like pin 7 on the solder side there ;-)
 
Looks like this monitor has spend some serious time in water. I have all the luck. The grounding strap was even rusted off, but other than some mildew the boards didn't look too bad.

When I got it, I had no picture but I did have neck glow, deflection chatter and the spot killer was coming and going. I'd lose deflection chatter when the spot killer came on. No HV. I only ran it for a few minutes like that.

So after recapping (and reflowing) it I had no picture, but I did have neck glow, deflection chatter and the spot killer was off. Didn't look like I had much going on in the HV department either. I cranked the contrast all the way up and could see a VERY faint hazy glow then I turned it off. I noticed Q708 got pretty hot after the reflow but before the recap so I replaced all the frame transistors with known good (but old) transistors. I assumed I'd probably nuke one of them if there was still an issue with the deflection board. Looks like there is.

Today I powered it back on. Neck glow, deflection chatter, kinda blinking spot killer and no HV. Getting 35V off pin 1 on P500 so I assume the HV section isn't completely dead. Q708 got nice and toasty and before I could power down, I smelled the blue smoke. Didn't see any fire, but R718 and R713 are burnt. All the fuses seem good (F700 has a 3A in it it though - supposed to be 2A - maybe an old "fix"). The two burnt resistors aren't all that bad so it's possible (but doubtful) that I missed them. Of course the only picture I took of the board is the one at the top of the thread, and each of the components in question is blocked.

So what's SOP? I'm going to start metering around the 700 section looking for shorts (I believe I need to remove the transistors from the circuit to do so, right? Anywhere in particular I should focus? I checked DB100 per Dokert's instructions in another thread, and it looks correct so I think that guy probably works.

At any rate, I think this monitor is going to be beyond my newbie skills :( There's just too much going on with it!
 
Okay, so the first thing you need to do is one thing at a time. I'm sure it needed all that stuff done, but when you do it all at once and the symptoms change, you don't know what made them different. So stick to changing one thing, test, repeat. Single best piece of advice I have for you, honestly.

You have a lot going on. It's going to be hard to fix a deflection problem you can't see, so I would pull F600 / F700, unplug the frame transistor harnesses, then work through the HV. There isn't much in between P100 and the HV cage, but there is some stuff, and I've seen deflection boards cause some truly weird issues that you'd expect to be problems in the cage. It sounds like you have some working monitors, so I'd swap the cage from this one into one of those, which will tell you if it's okay or your problem is on the deflection PCB.

Okay, deflection. First of all make sure your new frame transistors are good and aren't shorted to the frame. R718 blowing is often a sign of issues with those bottlecaps. Next pull and test every transistor in the 7xx section. You want to test them all. After that, it's time to brute force your way through the passive components. Comparing to a known good board can be extremely helpful here. There are two resistors different between the 15" and 19" boards, so make sure you know which or compare the same type of board.

Good luck.
 
I hear you with the one thing at a time, I just figured if I had it apart I'd do the full cap kit.

This is the only 19" vector I have. My others are 15". How interchangable are parts? Are the G05-802 and -805 HV cages identical? I know the deflection boards are slightly different but I imagine that just relates to image size.
 
I hear you with the one thing at a time, I just figured if I had it apart I'd do the full cap kit.

This is the only 19" vector I have. My others are 15". How interchangable are parts? Are the G05-802 and -805 HV cages identical? I know the deflection boards are slightly different but I imagine that just relates to image size.

They're all interchangeable, but the image will be too large or small if you swap a 15" board into a 19" monitor or vice versa. The only difference are two normal 1/4 watt resistors, so it's trivial to convert. See the schematics for specifics.
 
They're all interchangeable, but the image will be too large or small if you swap a 15" board into a 19" monitor or vice versa. The only difference are two normal 1/4 watt resistors, so it's trivial to convert. See the schematics for specifics.

Except for the G05-801, I believe that one is unique, but all the others, G05-802, G05-803, and G05-805, and V2000 are interchangeable.
 
Except for the G05-801, I believe that one is unique, but all the others, G05-802, G05-803, and G05-805, and V2000 are interchangeable.

Yeah the -801 is an oddball and nothing but the tube is swappable. But I don't think they made 15" versions, and they're much less common.

Having spares is very helpful. I have one extra 15" G05 with a pretty rough tube just for testing.
 
Looks like the HV board blew a resistor too. I seem to have a lot of issues.

The good news is that the tube works (sans the center spot of burn in)

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This is the deflection board and HV unit from my extra G05-805. Tube is mostly dead on that frame, but this one looks good! Still need to fix up the original boards though :(

Looks pretty good considering I didn't adjust the X and W width on the AD pcb. And the yoke is even centered!
 
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