Hi all, I wonder if someone might be able to advise and share their expertise. I attempting to resurrect a SONY WM-BF60 which has great sentimental significance to me. I think I received it aged 7 years old in 1985 and it filled me with awe and wonder about sound, something that later lead me into a career as a documentary sound recordist many years later. So I’ve taken the back off it and cleaned the internals using isopropyl alcohol. I had to desolder two sets of wires (black/red & blue/orange) and also disconnect one of the ribbon cables in order to partially separate and flip over the main circuit board for more through inspection. When I did this I noticed several things: 1) One of the 220/4V capacitors had detached itself and was floating around 2) The drive belt was slack and not connected properly 3) A White plastic thin block with 2 metal prongs coming out of the top of it at right angles to the block itself was desoldered on one side – not properly connected So from this I had several question I thought someone may be able to shed some light on: 1) I need to replace one of the 220/4V capacitors which has come off the PCB and I thought it best to buy a new one but if I’m going to do that is it worth buying 8 so I can replace the whole lot? I’ve heard it is sometimes wise to do so as old ones leak and can result in poor audio quality? There are also 5 narrower, slimmer components that look like the 220/4V capacitors but don’t have any markings on them…Should I try and source/re-solder/replace these are leave them be as they are? 2) I will need a new drive belt and advice on how to attach it to this model. I’ve found a supplier on Ebay who seems to have the model specific belt. Most people I’ve heard replacing belts seem to buy a big bag of assorted belts and use the one which fits best. Should I do this or go with the specific belt? Seems a daft question but I’m just doubting the specific belt is actually THAT SPECIFIC as there can’t be many people wanting to fix my model of Walkman! 3) I’ve cleaned the internals with Isopropyl alcohol but have some Servisol Foam cleanser 30 and Servisol Super 10 switch cleaning lubricant. Should I spray the cleaner all over the PCB and components etc? And should I use the switch cleaner on the tuning block, volume knob and other switch funtions? 4) I feel like I need to re-grease the sprockets/cog wheels and maybe some other parts. Can anyone recommend what type of grease and where to put it? That’s all my questions for now and if anyone is able to offer advice I’m very happy to send more photos and answer further questions Best Paul
1) it makes sense to go for a full recap but if you do not know the values then don't. Use your DMM to check the value of the 'floating' 220/4 cap, is it within specs? 2) I bought a few bags of belts from different eBay and Amazon sellers and they are all pretty bad. The best ones from my lots can be used for the counters but not for anything else. There must be some good kits out there, but nowadays I do not even waste my time and buy belts individually for each project. The best belts for Walkmans made by our member @mihokm, his eBay shop is here: MIHOKM 3) gentle cleaning with IPA and q-tips should be more than enough. I use DeoxIt for volume pots, it magically removes scratchiness. To answer your Q: I actually cover the rest of the board with a paper towel so that DeoxIt cleaner won't overspray all over the place. My best friend while fighting dusty/dirty boombox boards was an air compressor, at 35psi the boards became like new clean 4) i use SuperLube grease, unlike motor grease it is safe for plastics and does not seem to ever harden (but that will take another 20 years to actually prove). White Lithium grease is safe for plastics, based on what I see in 30+ y.o. discmans it never hardens. For metal-on-metal parts like capstan one of the professionals at Tapeheads recommended synthetic motor oil, I use Mobil 5W-30. A few days ago I finished restorations of Sony CDP-102 and CDP-302 for my neighbor, here is a photo of the oils used: Hamilton Gastight syringes with 25G blunt needle is pretty convenient for precise application of 5W30
Hi Jorge, Thanks so much for answering my questions point by point...very helpful indeed. I have indeed been in touch with mihokm and I am asking him if I can purchase a belt from him for my project. By the sounds of it I'll need to learn how to test the copper traces on the PCB using a multimeter and potential have to replace worn areas with thin wire and also maybe replace some of the pads the capacitors are soldered to. Lots of learning on youtube! Many thanks for your input Paul
