I recently acquired a non -functioning wm-30 in decent cosmetic condition. I cleaned all the belt goo, and cleaned the leaf switches but it will not power on. The battery contacts are clean. I checked continuity on the small section of the audio board where the leaf switches are and everything is connected, but I don't have 3v on on the connection labeled 10 at the end of the flexible cable connecting to the audio board. I also don't have 3v coming out of the converter board to the servo board. I guess Q804 might be blown if I'm not getting 3v? Is there something else I should be checking? This is my first attempt at a walkman repair but not my first cassette machine repair but far. Any help would be appreciated here. I'm happy to supply photos, measurements, etc as well. Thanks
For these to power up the headphone needs to be connected. Inside the audio jack there is a switch that closes when inserting the jack. Check if you get continuity on that switch when the headphone jack is inserted. If that switch doesn't close there will be no power to the board.
It doesn't power up with headphones connected. the leaf switch for power has continuity between the two sides when play is engaged.
I wasn't talking about the leaf switch....read my previous post carefully and look at the schematics.
Sorry I misread your post @Black Fingers. I found two broken traces on the cable connecting to the headphone jack. the headphone jack itself is cracked, which is probably what allowed enough movement to tear the flex PCB. I guess I'll see if I can repair the broken traces
Great you found the problem! Best to do is run some thin wires from point to point. Soldering the flex cable itself is not recommended, i've tried to fix one on a discman without any succes...ran some thin wire taking from old headphone wire...problem solved direct connection P2P. Good luck with the repair, let's us know how it ends!
The WM-30 doesn't have that switch in the jack anymore, that is only on WM-10 and WM-20 series. However it is to be noted the motor servo needs 3V from the DC-DC convertor to run and so does the Dolby NR circuit and head preamp.
I was successful in repairing the broken traces on the flex board connecting to the headphone jack. What would make the DC DC converter fail? Reverse polarity? Is it worth obtaining another wm-30 in hopes of swapping the converter board? Or something else?
In the DC-DC converters capacitor can fail, transistor and even the transformer. They can simply fail even without reversed polarity. Have you checked the 3V rail ? Don't assume the DC-DC is bad just because it's a potential fault. Does the power led light up or not ? If not it means you're missing the main rail from the battery also.
Thanks Valentin and Black Fingers. I spent some time checking connections along the 1.5v power rail from the battery to various points and all were connected. I had been testing with the audio board unscrewed. Perhaps I was missing a ground connection by having the audio board disconnected and folded over the side because I screwed it back on in order to more easily check connections on the converter board. Once the audio board was screwed in, the motor spun no problem. I installed a belt and stuck a tape in. It played ok and I started to adjust the tape speed but I found that operation was intermittent and was affected by wiggling the headphone jack. In that case, I will revisit the trace repairs I made and try to do a better job.
Would be interesting if your has that swtich in the jack. Nerver seen a WM-30 to have it (and it's not on schematic either), but given your statements it seems yours does. Is your model a WM-30 or a WM-10II ?
It's a wm-30. I will post pictures of the back of the headphone jack when I get a chance to remove it again tonight or later this week
@Valentin just checked the schems and it seems you are right, the WM30 should not have the switched jack socket but service manual versus real world might be different. i think the wiggling is co incidental with the actual fault. @Harry Klippton What do you mean by intermittent behaviour? Like does the wm power goes off and on? or is the audio dropping in and out? or is it running, stopping, running? please clarify... If you look at the schems block diagram you will see S901 in the power circuitry. This switch is seated underneath the take up reel. If this switch is not making good contact with the take up reel the walkman will not play, or play/stop ect. Mine also had intermittent power issues, after i cleaned and polished this switch and cleaned the surface of the take up reel all was working well again.... I also like to see a photo of the audio jack on your WM30.
@Black Fingers thank you. I will try to take pictures of the headphone jack tonight if I'm able. I just cleaned S901. I had previously confirmed its connections to the opposite end of the flexible board. By intermittent, I mean that it will run, stop, run, etc. it sort of groans to life. The LED slowly brightens up and the tape starts advancing. The transport can cut out at times (with the wiggling of the audio jack) and the audio is intermittent in frequency response, losing bass. The LED goes on and off too. Is it inadvisable to unsolder the headphone jack from the flexible board? It seems to me that removing the jack would allow for some more thorough cleaning, I could glue and clamp the cracked portion of the jack housing, and attempt a better repair on the traces
It does indeed play without a plug inserted in the headphone jack, but just for curiosity's sake, here are some pictures of the jack. last picture shows the damaged traces and my first attempt at repair which wasn't successful.
I made a pretty ugly but functional repair to the broken traces on the headphone jack. I pulled apart a broken wall wart, unspooled the wire from the small transformer and used that to make a few jumper wires. I used kapton tape on the torn flexible PCB and heavy duty double stick tape on the bottom side of the headphone jack to help it stay in place. Now the device is powering up, playing, fast forwarding, and rewinding. I'm using a generic belt that is the right length but it's slightly too thick. the belt tension pushes the center brass pulley into the small white gear behind it and interfering with the transport movement. I'm waiting for the correct belt from fix your audio. Hopefully that does the trick. I cleaned the playback head, capstan, and pinch roller too
That middle pulley sitting at an angle is a common problem on these WM-10/20/30 series (they all sit at an angle when belt is installed). Not sure if a thinner belt will necessarily fix it completely, but you can hope. Usually the bracket that holds the bushing of that pulley needs to be adjusted (by adding shims under it) so the angle changes to opposite of belt tension. The unfortunate part is much of the mechanism needs to be disassembled to remove that pulley: capstan/flywheel, buttons assy. What actually fixed the problem, cleaning the leaf switch more ? Was a bit confused initially, as from your description it sounded like the jack was the problem.
Im not totally sure but I think the problem was the traces leading to the headphone jack, specifically the two traces connected to the power switch labeled 1 and 2 from the audio board. Once I added the jumper wires and made the jack itself more stable, I couldn't recreate the problem. That's disappointing to know the middle pulley rubbing is a common problem. But if the player doesn't work because of it, I've got nothing to lose by further disassembling it to try and fix it
Great work @Harry Klippton I just took a good look at the service manual (page 21 & 22) to see what you fixed by tracing the pcb traces in the sm. Looks like you fixed the ground plain which is consistent with the behaviour you've had. Looks like the point where it broke/cracked on yours actually shuts down all the of the ground plain. Valuable information this, always check the flatcable and if you have continues ground throughout the machine.
