Sanyo EZ B+ high/won't adjust

mecha

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re-capped a EZ earlier and now the B+ is stuck at 122V

the B+ adjustment pot yields no change. tried following Dokert's flowchart, but does this mean the Q901 is bad, or is there something else I should check?

if it helps any, I only installed a standard kit, not Bob's deluxe one.
 
re-capped a EZ earlier and now the B+ is stuck at 122V

the B+ adjustment pot yields no change. tried following Dokert's flowchart, but does this mean the Q901 is bad, or is there something else I should check?

if it helps any, I only installed a standard kit, not Bob's deluxe one.

Step 1: Travel back in time and install the deluxe kit.

Seriously though, I don't know if the deluxe kit would address the issue or not but since you're going to all the hassle of disassembling that beast, why not spend the extra $4 and time to make it "bulletproof"?

I believe I read somewhere that at least one person who had this problem had a bad B+ pot. On my two Sanyos I just spent the extra buck and replaced it as well, just in case.

Anyway, I remember seeing at least 3-4 threads on this in addition to Dokert's excellent flowchart, some search fu should get you on the right track.
 
Check the pot itself, it could be bad - I've seen a couple fail. At 122v, it almost seems low for the thing to be in HV shutdown - usually the B+ goes to like 140v. Is the monitor working?

If it's in shutdown, try turning down the board mounted brightness pot, then turning the monitor on again - if it's up all the way, then sometimes they go into shutdown.

If it's working, but you can't adjust the B+, it could be a problem with the regulator transistor (2SD1090), or the regulator IC itself. I've had to replace a regulator IC for the same reason - couldn't adjust the B+. Only in that case, the monitor was always stuck in shutdown.

-Ian
 
Step 1: Travel back in time and install the deluxe kit.

Seriously though, I don't know if the deluxe kit would address the issue or not but since you're going to all the hassle of disassembling that beast, why not spend the extra $4 and time to make it "bulletproof"?

I believe I read somewhere that at least one person who had this problem had a bad B+ pot. On my two Sanyos I just spent the extra buck and replaced it as well, just in case.

Anyway, I remember seeing at least 3-4 threads on this in addition to Dokert's excellent flowchart, some search fu should get you on the right track.

it's actually a 20-Z2AW. the last time I asked about it, nobody replied. which makes me wonder, do those take the entire same cap kit as the EZV? the bottom monitor I did on my PC-10 came out looking fantastic after I adjusted it since the colors were all messed up after capping it (monitor was abused by heavy brightness, etc.), this one is for the top monitor. Bob says for these you just use the standard kit, and so I just left it at that. if so though, I have deluxe kits that I can pull the extra caps from to make them complete.

I made a mistake when I put this monitor back together, you know the forked ground terminal that screws to the frame? I forgot to reconnect that, and I don't even know why. it went into HV shutdown immediately, I think the B+ was about 130. reconnecting that made it turn on, but now the B+ is at about 122V

so yeah, it works now, but it does the hula.

are the parts interchangeable between this and an EZV? also, what is the red wire for that goes to the inverter board? I tried hooking an EZV up direct and it pops the small fuse, I read that running without the inverter can do that, and the EZV lacks the red wire that goes to the 3 pin header at the top of the inverter board.

EDIT: to reiterate, this is for a PC-10 dual monitor, hence the inverter board stuff. :)
 
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it's actually a 20-Z2AW. the last time I asked about it, nobody replied. which makes me wonder, do those take the entire same cap kit as the EZV? the bottom monitor I did on my PC-10 came out looking fantastic after I adjusted it since the colors were all messed up after capping it (monitor was abused by heavy brightness, etc.), this one is for the top monitor. Bob says for these you just use the standard kit, and so I just left it at that. if so though, I have deluxe kits that I can pull the extra caps from to make them complete.

I made a mistake when I put this monitor back together, you know the forked ground terminal that screws to the frame? I forgot to reconnect that, and I don't even know why. it went into HV shutdown immediately, I think the B+ was about 130. reconnecting that made it turn on, but now the B+ is at about 122V

so yeah, it works now, but it does the hula.

are the parts interchangeable between this and an EZV? also, what is the red wire for that goes to the inverter board? I tried hooking an EZV up direct and it pops the small fuse, I read that running without the inverter can do that, and the EZV lacks the red wire that goes to the 3 pin header at the top of the inverter board.

EDIT: to reiterate, this is for a PC-10 dual monitor, hence the inverter board stuff. :)

So by "doing the hula" do you mean it's waving slow like a flag in the breeze? That's typically the filter cap, C606 in the 20ez at least. I'm not knowledgeable enough to say whether or not this could be related to your B+ as well.
 
high B+ will do that I'm told. it does it along the sides. unlike my DK, which does it up and down (across, essentially) the entire screen, which is a bad VR (IC601 right?)

what's the likelihood I just broke the B+ pot when I was trying to get the white-out looking stuff to break free? is the B+ whatever it wants to be, and that pot is just for fine-tuning it, not necessarily specifying what the B+ really should be?
 
I have seen the B+ pots go bad before. But they're easy to check with your meter.

The wavy picture thing is caused by a problem in the B+ supply - usually a bad filter cap, but sometimes just because it's way out of whack.

I'd check the B+ pot with the meter to rule that out. Try replacing Q901, and if that doesn't do anything, IC601. Not much else in that circuit.

-Ian
 
Turn the brightness on the flyback down a little, as it is directly related to you B+

tried that too, the G2 I have adjusted right where it needs to be, cause it either goes retrace lines or it's pitch dark. brightness is where it needs to be too, where the black background is entirely black.

the change there was negligible, I think it got me from 122.8 down to like 121.8.
 
The cap kit should be the same. I have 2 of those monitors and a few ez's and I've used the same cap kits in all of them with no problem. I have the inverter boards completely out of my monitors and have no problems. The inverter has nothing to do with the rest of the chassis. -Barry
 
pardon my ignorance, but I've tried like every combination of testing the legs on the pot, and isn't it supposed to be a 5k pot? it changes, between the 2 extremes, I'm not entirely sure how to meter it and move it with a screwdriver, lol.

I don't know, one way I tried doing it, the numbers kept climbing. I ran it on 20k ohm test.
 
pardon my ignorance, but I've tried like every combination of testing the legs on the pot, and isn't it supposed to be a 5k pot? it changes, between the 2 extremes, I'm not entirely sure how to meter it and move it with a screwdriver, lol.

I don't know, one way I tried doing it, the numbers kept climbing. I ran it on 20k ohm test.

Those B+ pots are notorious for going bad, try replacing it.
 
Clip black to the middle leg, clip red to one of hte others. Move it with a screwdriver, it should go from 0 to the max resistance (or vice versa). If you move the red leg to the third leg, it should go from the max resistance to 0 (the opposite of the first one). If it doesn't move smoothly through the range, or if it doesn't reach max resistance, or it doesn't move at all etc, it's bad.

It's a cheap enough part that I'd just replace it anyway (I believe this marks the 5th or 6th time you've been advised to do so in this thread alone :p)
 
Clip black to the middle leg, clip red to one of hte others. Move it with a screwdriver, it should go from 0 to the max resistance (or vice versa). If you move the red leg to the third leg, it should go from the max resistance to 0 (the opposite of the first one). If it doesn't move smoothly through the range, or if it doesn't reach max resistance, or it doesn't move at all etc, it's bad.

It's a cheap enough part that I'd just replace it anyway (I believe this marks the 5th or 6th time you've been advised to do so in this thread alone :p)

funny guy (big difference between having time working on a game in a garage and doing my daily job). thanks for the testing tips.

should I borrow a Q901 off one of my other EZVs too? I was thinking of hitting up Radio Shack today, can I get a replacement B+ pot from there?
 
funny guy (big difference between having time working on a game in a garage and doing my daily job). thanks for the testing tips.

should I borrow a Q901 off one of my other EZVs too? I was thinking of hitting up Radio Shack today, can I get a replacement B+ pot from there?

I don't believe Rat Shack has the right value pot. I've gotten mine from BR but he was the source of my cap kit in the first place so it was convenient. Dunno if they're available from Jameco or similar.

EDIT: I might be mistaken, but I think it's a 5k ohm pot. If that's the case, this 10k ohm one might work for you, but you'll lose a lot of fine-tuning on the control. I'm sure someone will correct me if this is an incorrect statement. http://www.radioshack.com/product/index.jsp?productId=2062301
 
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I'll just snatch one off one of my other monitors. then I'll buy replacements later I guess. I'm sure Alice Roberts is kinda pissed at me, I was a little late with sending the check lol
 
all fixed, I just snagged a Q901 and VR and a 5k pot off a WG remote board I had laying around. looks beautiful now.

I got B+ on both monitors running at 108.1V.

it was more than likely the Q901 at fault, cause replacing the pot made no difference, but I suspect that the pot was broken anyway, cause it wasn't even hitting 2k ohms at its max.
 
B+ Wpes

I was wondering what VR you are using for this replacement? My Sanyo 14EZ has a C1051, which I do not see listed anywhere. So should I be using the 2SD1090 that I see listed? I am trying to find the correct part to order or a cross after replacing IC601 and the HOT this looks like my last problem area.
 
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