Announcement

Collapse
No announcement yet.

Randall Warhead WH150 Input Jack Dilema - Please Advise

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Randall Warhead WH150 Input Jack Dilema - Please Advise

    Hello. I have a Randall Warhead WH150 amp head with a faulty input jack. It’s a 5 pin 1/4” jack that solders onto a little pcb board. I ordered the exact replacement jack and installed it. I only get signal when my guitar cable is in HALF way in. No signal when all the way in. I can’t find a schematic anywhere. I’ve emailed Randall twice last week, with no reply. I’m confused as to why they used a stereo input jack. I’ve tried jumping the pins but no signal. Did I order the wrong jack? If so, can someone please advise me a correct replacement? Pics below. Thanks in advance for your time and knowledge!
    Coop

  • #2
    Is the original jack functional enough to test the continuity of the various pins? Maybe the new jack looks identical but has a different pinout. The stereo jack makes me think there is a mute function that is being switched off when a jack is unplugged.

    Comment


    • #3
      I see only two connections to the board- probably signal input and ground. So, there can't be a lot going on there. A standard shorting jack with a cap from tip to ground. Just insert a plug and figure out what goes to what. The plug tip should go to the signal + wire and sleeve to ground. Maybe wrong jack, maybe through holes broken during unsolder, etc. I'd probably just install a regular shorting jack, put the cap on the jack solder pins, solder the wires directly to the jack, and throw the circuit board in the trash bin.
      "Yeah, well, you know, that's just, like, your opinion, man."

      Comment


      • #4
        Originally posted by glebert View Post
        Is the original jack functional enough to test the continuity of the various pins? Maybe the new jack looks identical but has a different pinout. The stereo jack makes me think there is a mute function that is being switched off when a jack is unplugged.
        I see only a single shielded cable to the little circuit board, so I don't think there could be a separate mute circuit. It would require more connections to the board.
        "Yeah, well, you know, that's just, like, your opinion, man."

        Comment


        • #5
          Did you order this from Randall, I mean is this an official Randall jack? Or did you order the "Identical" jack from anther source? I used to replace jacks that look like that in some product, maybe Behringer, except the innards were reversed. In other words the tip and ring contacts were on the opposite sides. It sounds like this is what you have.

          Does the new jack have SWITCHCRAFT molded into the body around the bushing? Does the old one?

          Look at the photo of the old jack, the angled corner is the sleeve/ground. At the top is the ring contact, and upper left is its cutout. Over at 3 o'clock is the tip contact and lower right is its cutout. I assumed that was the old jack. In any case, compare the new and old jacks inside to see if they ar the same or reversed.

          You could just wire up a plain old #12 jack, but note the old one has an insulated bushing, so grounding that jack to chassis COULD make hum issues. Might or might not.
          Education is what you're left with after you have forgotten what you have learned.

          Comment


          • #6
            Originally posted by Enzo View Post

            Look at the photo of the old jack, the angled corner is the sleeve/ground. At the top is the ring contact, and upper left is its cutout. Over at 3 o'clock is the tip contact and lower right is its cutout. I assumed that was the old jack. In any case, compare the new and old jacks inside to see if they ar the same or reversed.
            I think with these jacks you can depress the locking tab and slide the pins out, rearrange the position to match the old jack. It's tricky and you have to do it in order, but it can be done.

            "Everything is better with a tube. I have a customer with an all-tube pacemaker. His heartbeat is steady, reassuring and dependable, not like a modern heartbeat. And if it goes wrong he can fix it himself. You can't do that with SMD." - Mick Bailey

            Comment


            • #7
              Yes, I have done that many times, I just didn't want to go there before we found out he needed to. I had a collection of those little thins in my jack collection. I sometimes made 2-tip jacks by adding a second tip feeler. SO yes, if that turns out to be the problem, we can convert the new jack to fit the old board.

              Or just wire up a jack without the board.
              Education is what you're left with after you have forgotten what you have learned.

              Comment


              • #8
                As it works with Inserting the plug halfway I'm thinking the ring contact is connecting instead of the tip. When the plug is fully home the sleeve is shorting out the signal.

                Comment


                • #9
                  Thanks guys for all your input! Pun intended! lol.
                  I took your advise and just done away with the little input board, and wired it straight to the jack with the .001uf cap across tip and sleeve pins. Works great now! I was way…. Overthinking this! I was trying to keep it 100% original, but sometimes we do, what we gotta do.

                  I ordered the jack from Amplified Parts. It was a Peavey jack, supposedly. Someone may have tried fixing it before me, and used the wrong jack. Idk. But, I emailed Randall twice last week and they never replied. But all is well now. Thanks again for all your help! Rock on!
                  Coop

                  Comment

                  Working...
                  X