Ad Widget

Collapse

Announcement

Collapse
No announcement yet.

Peavey TubeFex Blank Screen

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
  • #1

    Peavey TubeFex Blank Screen

    Hello All, It has been awhile. Anyhow I just dug up an old Peavey TubeFex. When I power it on, the tubes fire up ok, but only displays a blank green screen. I tried to re-initalize, down and right arrows, and no luck. This preamp also has the non volatile ram, battery upgrade. Any ideas? I know Enzo has probably seen this before. I also have opened her up and looks absolutely spotless, I cannot see anything that sticks out. Reseated all chips also, maybe bad dsp chip? If anyone can help, than you in advance. Cheers!
    Tags: None
  • #2
    "Seen this"? You have a system not running, it could be anything. So I suppose I have seen it, but that's no help.

    Start at the start, are all the voltages present? PV customer service will be happy to send you schematics.

    As a point of pride, I don;t like sending anything out, but in the case of complicated things like this, I might just box it up and send it to Peavey. They have every resource there is, and their rates are reasonable.
    Education is what you're left with after you have forgotten what you have learned.

    Comment

    • #3
      schematic here:
      http://music-electronics-forum.com/a...76-tubefex.pdf
      Originally posted by Enzo
      I have a sign in my shop that says, "Never think up reasons not to check something."


      ​

      Comment

      • #4
        I'll stipulate first that I have no certain idea what's causing your problem without more info.

        That said, the times I have run into this problem, it was because a leaking battery ate through traces and feed throughs in the battery area. I realize you no longer have a battery, but there was one in there at one time, so look over the battery area of the PCB and make sure nothing has corroded away.
        "I took a photo of my ohm meter... It didn't help." Enzo 8/20/22

        Comment

        • #5
          Originally posted by The Dude View Post
          I'll stipulate first that I have no certain idea what's causing your problem without more info.

          That said, the times I have run into this problem, it was because a leaking battery ate through traces and feed throughs in the battery area. I realize you no longer have a battery, but there was one in there at one time, so look over the battery area of the PCB and make sure nothing has corroded away.
          I just gave it to my tech, I'll reveal what trace(s), etc... or whatever the issue was when I get it back. Thanks Enzo and Duder.

          Comment

          • #6
            If it is corrosion, these can get quite tricky. If I recall correctly, these are multilayer boards. Have him check especially feedthroughs in the battery area. It's often necessary to run new jumper wires when traces are completely gone. Before you even start, if there is evidence that battery leakage has occurred, spray an anti corrosive/cleaner over the area to prevent further damage to traces. IF YOU DON"T DO THIS, YOU ARE WASTING YOUR TIME! Things will continue to corrode away over time if you don't get all of the "battery goo" cleaned up and it will eventually come back to bite you in the a$$. If your tech doesn't have one, Peavey is very good about supplying schematics and even board layouts if they have them. Good luck!
            "I took a photo of my ohm meter... It didn't help." Enzo 8/20/22

            Comment

            • #7
              All the more reason to send it to PV. Their synths have a nicad memory battery that leaks, and the whole board gets spooged. They just clean the board down to the copper and repopulate it for cheap. - like new. I'd approach this the same if there are battery failures.
              Education is what you're left with after you have forgotten what you have learned.

              Comment

              • #8
                Originally posted by The Dude View Post
                If it is corrosion, these can get quite tricky. If I recall correctly, these are multilayer boards. Have him check especially feedthroughs in the battery area. It's often necessary to run new jumper wires when traces are completely gone. Before you even start, if there is evidence that battery leakage has occurred, spray an anti corrosive/cleaner over the area to prevent further damage to traces. IF YOU DON"T DO THIS, YOU ARE WASTING YOUR TIME! Things will continue to corrode away over time if you don't get all of the "battery goo" cleaned up and it will eventually come back to bite you in the a$$. If your tech doesn't have one, Peavey is very good about supplying schematics and even board layouts if they have them. Good luck!

                This unti had the battery mod done a long time ago, I also sprayed the whole battery area of the PCB with Deoxit before I gave it to him. He also has a bunch of other Peavey Transefx? so he is well versed with this issue. And they are multilayer boards, 4 I was told. I also have the schematic with layouts. Thanks for the tips anyway, I did notice a little lite green blob in the neg battery terminal on the underside of the board which sprayed the crap out of. Whoever did the initial mod did not check for left over corrosion. Thanks guys!!!

                Comment

                Previous template Next
                Working...
                X