After replacing the belt on a wm-F75 I find two loose wires that broke or came loose. One is dark gray (maybe black), the other wire is white. They seem to terminate near the DC input. I can't see any obvious points to connect them. Somehow, the cassette player is working despite this. Can anybody help suggest where they go? Thanks EDIT: I have been testing the unit to see how it performs with the new belt, looking for issues, etc. Side A plays fine but if tape direction button is pressed, the audio is still Side A program but playing backwards.
I took some time off and then came back to the project with some fresh eyes. I was able to find the switch that was meant to be connected to the loose wires. No doubt this was caused by me when I replaced the belt. The service manual shows this leaf switch as s902 (head select). Now I need to figure out how to re-solder the switch without melting other wires located near the switch. It's tight fit in there but maybe I can remove the switch to re-solder it.
It was fairly simple to open the case after seeing the service manual. The manual shows in detail but to summarize, I had to remove the tuning and volume knobs and a few switches, which are covered with adhesive ornamental covers. The covers are just adhesive stickers which can be picked off with a sharp point. I used a sewing needle and was able to get them off without damaging them. There are also a handful of screws hidden under "ornamental" covers. Once the knobs and screws are removed, the chassis can be slid out of the case.
When I tried to upload the manual, I got a message saying the file was too large. Here is a link to site where I found the manual. https://freeservicemanuals.info/en/servicemanuals/viewmanual/Sony/WMF75/
I managed to re-solder the leaf switch and this walkman works nicely again! Now I need to re-insert the works in the case.
I am now listening to my repaired walkman! Persistence finally paid off! It took three attempts to re-install the works into the cabinet. It's all too easy to break the thin wires for the battery and headphone jack. I broke the DX/Local switch but I can live without that.
Thank you for this. I immediately downloaded the manual and will pull my wm-f75 apart when the new belt arrives.
I found out that this model can play Cr02/Metal tapes because the leaf switch S303 is infact used for detecting the Cr02 notch which uses 70us...and so does Metal. In the service manual the block diagram simply calls it an '(ATS)' but reading the schematic S303 the passes thru Qs 101 & 201 (each for both play directions) and beside them printed in red are the required voltage readings for Normal & Metal playback. You could say a wolf in sheeps clothing and Sony didn't exactly advertise it. But even today's buyers seeing 2nd hand ones with out any boxing to advertise the fact would be unaware that could play such tapes.
Don't you hate the scenario of having a broken selector switch, I find a seller then being an Australian I enquire then they reply "oh we only post to Europe". Makes me want a relative living there to make the purchase. https://fixpart.co.uk/en/product/sony-157011411-switch
