Adjusting B+ Voltage on a Sanyo 20EZV - What Am I doing wrong?

mhanlen1

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Adjusting B+ Voltage on a Sanyo 20EZV - What Am I doing wrong?

Ok, I feel like a moron but I can't get a reading off the BJ pot. I'm pretty sure I have everything right, but here's some pics- so maybe some one can tell me what the hell I'm doing wrong. I suspect it's my multimeter. Although it was new, it was given to me in a box of junk in it's original unopened package. I have no idea how old it is. When I flip around the dial I do get random numbers when I have it connected, so it seems to at least work- but I'm not sure if it works correctly. Anyway, maybe it's OE so tell me if everything looks hooked up OK.

Here's my set-up. You can see I have my multimeter on my chair and my wires running to the cab.


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Here's where I have my ground.


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It was hard to get a good shot in here, but through it's blurriness it's connected to the B+. I have Dokerts B+ tester cable connected to it all, which by the way works way better than an alligator clip in such a tight spot, where there's high voltage and no finger space.

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And here's my multimeter. While the monitor is not on, this is where I think I'm supposed to have it set... right? Are all the cables connected correctly into it? By the way the selector arrow is at about 11 o'clock.



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So anyone know what's going on? All caps, even the C606 are all brand new. Why wouldn't I get any reading at all? As far as that B+ cable being the weak link- well I've done this before with alligator clips with the exact same result. As far as adjusting the B+ pot itself, I know how to do it, but before doing so I'd like to get a reading.
 
You've got the red lead plugged into the wrong spot on your meter....plug it in to the other spot.

Edward
 
I had tried both in the past, but to no avail. Anyway trying it again I just plugged it into the other, and I get a reading of "00.4" Which can't be right.
 
Maybe you need to rotate the meter's knob 180 degrees...as in, right now it's set on hFe.

Or....maybe it's time to get another meter :)

Edward
 
I tried rotating the knob, to every possible point on the dial, and never got a reading close to what I should be. So, yeah I'm going to have to make a trip to Radio Shack, despite exceeding my Donkey Kong budget this month. $28 for caps, $45 in coin mech parts, and now another $50 on a decent multimeter. Dammit.
 
The selector looks like it's in the right position, the Red lead isn't right as stated. It needs to be in the Volt/ohms port. Also. If you were rotating the selector while it was connected to a voltage source you may have fried it. I've seen plenty of meters trashed because of this. But it could also be a fuse. Put it on 20 and try it on a 9v battery or similar and see what you've got.
I would also try moving your ground clip directly to the monitor chassis, it may be that you don't have a good connection. Paint, rust, etc.
 
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Well, first off, that's not a 20EZV, but an 18ZAB. Still, TP-91 should be your reference point for the B+ check, correct? Your red lead should be attached to that (with it in the lower spot on your meter), and your black lead should be attached to ground (use the monitor frame).

Also, make sure the monitor is getting power. If not, you won't get a B+ reading...
 
The selector looks like it's in the right position, the Red lead isn't right as stated. It needs to be in the Volt/ohms port. Also. If you were rotating the selector while it was connected to a voltage source you may have fried it. I've seen plenty of meters trashed because of this. But it could also be a fuse. Put it on 20 and try it on a 9v battery or similar and see what you've got.
I would also try moving your ground clip directly to the monitor chassis, it may be that you don't have a good connection. Paint, rust, etc.

I just got back from lowe's after buying a new multimeter.

So I followed your advice, and tested a 9v and sure enough, I got a reading. I should have done this in the 1st place. Continuing to follow your advice, I removed the clip from the cab chassis and clipped it to the monitor frame. Bingo! 113 volts.

When I tried this a month ago I wound up blowing a fuse, and figured that was the reason- because I clipped it to the monitor. Anyway I must have inadvertently touched something shouldn't and that's probably what did it.

Anyway, I'm going to rig up a straw/monitor tweaker rig and adjust the B+. Thanks a lot. I going to go and set it at 108 now.
 
Alright so I'm kicking myself trying to figure out what I'm doing wrong on my Donkey Kong in another thread. So I decide to read monitor manuals. The way I understand is there's 2 different sizes of the Sanyo monitor. I have the smaller one, in which there are slight differences. After reading both manuals that I downloaded from Mike's Arcade I've found that the 14" and 19" have two different B+ settings. While the 19" is 108 the 14" which I'm pretty sure is mine is supposed to be 105 volts.

That's a big difference from the 113 it read originally, and even the 108 I have it set at now. Ok, well I'm going to try that then. Anyway, not a big deal, but I've read multiple times 108, and I guess most people think it's the same for the 14"- which I don't think is correct. Please anyone feel free to read the manuals and share opinions.
 
To make things (even) more confusing....there's actually a third size. It's in between the two you posted. Not too mention, Nintendo used Sanyo brand and Sharp brand monitors.

Also, A couple volts here-or-there isn't going to affect the monitor reguarding the B+. I agree, 113VDC is a little high for something that needs 108 (or 105)....but 108 vs. 105 is a non-issue.

Edward
 
Well I dialed it back to 105, and it still behaves the same. And looking at both board schematics mine is more like the 14" than the 19", but there are still differences. God, what a fucking pain in the ass.
 
Just curious....do you know the actual model of you monitor? Nintendo's can be tricky.

Also, Do you own another Nintendo machine? Something you could swap the monitor into....see if the problem follows...

Edward
 
I have no spare parts. I'd love to troubleshoot by part, but have nothing I can swap in. It'd be great if I could find another (working or not) unit for spare parts on the cheap, but cocktails don't come up very often around here (DK or not). If I had a spare one, I probably wouldn't be bugging everyone on here with these incessant questions.

As far as model number... there are several markings all around the chassis:

If you're looking at the tube (like your playing a game) theres a sticker that reads "14-5FRB" the sticker also has TGK and some japanese characters on it.

While normally it's easy to tell on electronics what the model number is, I don't know where to look on this. It's all in good condition with a lot of the original stickers. What would the model number look like? I would guess it would have "14" in it somewhere. I see a lot of EZW and EZW-B stamped on a lot of the metal chassis pieces along with that particular pieces model number.
 
I see a lot of EZW and EZW-B stamped on a lot of the metal chassis pieces along with that particular pieces model number.

That's it....You probably havean 18-EZW....They might have made a 14-EZW. There should be a number associated with the "EZW"....that's what you have.

Edward
 
I measured it diagonally and it's definitely a 14" But looking all over, never are "14" and EZ ever together. The closest thing is the sticker on the viewing side that reads "14-5FRB."
 
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