Wells 4602 - no picture

msignor

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I have a 4602 with absolutely no picture. Turns on, I hear the high voltage.. but no picture. I turn up the flyback and brightness and nothing.

I ordered a capkit from zanen with the black pot.. is there anything else other than solder joints I should be looking at?
 
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Got a capkit from Zanen.

Installed all the caps, but some were not included so I was forced to leave the old ones.

I replaced the brightness pot and still have no change. When I power off I do see the monitor flash, and a bunch of color for a split second... which is an improvement over before.

Any ideas on where to go from here?? Should I get the caps that were not included?

-Matt
 
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Did the mobo headers, saw a bunch of cold solder. Didn't touch the daughterboard connector though, ill do that now and let you know.
 
Didn't want to have two threads ultimately on the same topic.

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I redid the joints on the daughter card itself with no change. Also adjusted the two brightness pots to max and no change. Is the pot on the neckboard prone to failure too?

It looks like the yoke (spelled it right!) connector to the chassis is not on all the way, but should be enough for some kind of connection. I don't want to really push on the PCB and just make more loose solder joints.

I will be testing b+ when I get home - Is there a flowchart for these? I wasn't able to hunt one down.. but probably didn't do enough googling / searching.
 
The black level pot on the video interface board is generally set to the middle of it's range which should produce a picture.

The "SCREEN" control on the neckboard should be set around the 10 o'clock position. It should never need to turned any higher, especially all the way up.

The male header pins on the monitor main board are well-known for numerous bad solder joints.

"Installed all the caps, but some were not included so I was forced to leave the old ones." Does this mean some of the caps in the list provided with the Zanen kit were not in the kit (in other words you were shorted a few caps that were supposed to be in the kit)? If so, call Zanen and tell them about the ones you were missing in your kit.
 
The black level pot on the video interface board is generally set to the middle of it's range which should produce a picture.

The "SCREEN" control on the neckboard should be set around the 10 o'clock position. It should never need to turned any higher, especially all the way up.

The male header pins on the monitor main board are well-known for numerous bad solder joints.

"Installed all the caps, but some were not included so I was forced to leave the old ones." Does this mean some of the caps in the list provided with the Zanen kit were not in the kit (in other words you were shorted a few caps that were supposed to be in the kit)? If so, call Zanen and tell them about the ones you were missing in your kit.

I will go and dial in the pots as you indicated and try again when I get home. When I power the monitor off, I do see a bright flash w/ rainbow colors for a split instant. I did repair many cold solder joints on those pins.. Not all, but the definate ones I could see were cold.

One more funny thing to note is that there is a 60in1 in here so when it first turns on there is a slight delay before you would see it verfying the ROMS anyway, I can hear the monitor turn on - then "sync" almost like a PC monitor when you turn it on and then you hear it almost lock onto a signal before it warms up.. Does that make any sense? I am not sure how to describe it.

I don't believe I turned the 800v neckboard pot all the way up. I hope I didn't :-/ How bad would that mess up things?

I wasn't shorted caps... and replaced all of the caps they indicated on their directions. However there are more caps on this chassis than they indicate to be replaced. I am guessing that this is because a 4602 had more parts than the newer 4606 etc???
 
adjusted all of the pots as well as ripped the chassis out and made sure of no cold solder.. i think I got em all... no dice. it sounds like it wants to work!! but alas, nothing :-(

At this point would it be safe to try and replace the non-replaced caps?
 
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