Hi forum, I purchased the (vintage) HF-S 160 from AIWA. LED and motor do run if powered by batteries. Disassembled the machine and found what I expected. Both belts gone, leaving a sticky mess. Small belt is a no brainer but here's my question: what about the larger belt under the PCB. I mounted a rubber band for manual test. Attached as an oval the reverse mode will not work properly, assuming the motor direction does not alter. If mounted as an 8 it works. What I don't know right now: does motor direction change when reverse mode is activated? This machine seems different from my SONYs. Any help would be highly appreciated. Thanks in advance for help. br G68 - yesterday falsely posted in boombox, I am sorry for this -
I know on the models using the 2ME-7 mechanism, such as the J36/360/85/10/9/09/600 the motor reverses direction for reverse play and rewind.
Thanks for the information. Got sorted it out by myself. Unfortunately now the motor does not spin. I disassembled the player, unsoldered the battery compartment, made a mockup with rubber bands and assembled everything back. But now the motor does not spin up. Power LED lights up. Unfortunately I am not good at electronics.
Update: I unsoldered the motor from the Motor CB. It spins when 1.5V are attached to the power leads. Seems some electronic part is corrupt. Power LED still works. Model is HF-S 160
Hi Steve, sorry, I have not yet made a photo of the MCB. But today I had a rampant learning curve. First I asked a colleague at work (electric engineer) about the layout of the MCB. He did show me where to measure voltage. Then I noticed: there is a PAUSE switch! To remount the case with all buttons I had switched all to one side for easier mounting. At that moment I engaged PAUSE. Today I cleaned the flywheels of the capstans, attached the new belts and: it works, a little bit. First, motor speed is too slow. Second, audio is low on output. And third, there is a wire damage at the flat wire from the head to the main PCB. At least, a small victory.
Ah, yes, the number of times I've worked on a tape drive problem because the Pause switch was engaged during testing... I'm currently working on a J600 that has low volume output. No solution yet. Probably there is a means to adjust the motor speed. Flat ribbon cables can be repaired, though it is a difficult job. There is a YouTube video by someone who is pretty good at it. You can also install fine wires between the terminals. People in China (Goofish/Superbuy) are making reproductions of some of these cables. But your unit probably is too rare to justify someone making the effort. I forget whether you have the service manual for the unit, but they are available.
Today a second player arrived at my home. Decent condition from sight, internals also. I switched the belts to the other player, mechanics run smooth but: no sound. I admit, I am a total noob considering electronics. What can I check with a mutlimeter in a side by side comparision? First difference I noticed is the difference in the potentiometer for volume. Any ideas? Thanks
You could try swapping the volume potentiometers. Not having circuit diagrams makes this more difficult. Without diagrams, even it you find a discrepancy between the two units, it's difficult to follow the problem upstream to the source. Comparing voltage is safer than checking for continuity. The latter can put too much power through integrated circuits. Something else you can do is go over the bad one using a magnifier looking for bad connections. Equalizers are problematic. If you can find Right-in and Right-out, and Left-in and Left-out markings, you can try bypassing the equalizer. You just short the in/outs. Or if the equalizer is a separate board, swap them between the two units.
Hi Steve - thank you for eyeing my thread! I followed your advise on how to fix ribbon cables on YT. I have access to the diagrams - but I am not able to read them. On archive.org the complete documentation is availlable. The EQ on the first player does work. Either way shorting or switching is possible. Bypassing might be the easier task. I already thought about swapping the PCBs between both units. Next step might be checking the jack for the headphones, they were quiet dirty on the second player. Will try some of it next sunrise. Thanks
Great idea to check the earphone jack. I find I have to remove and disassemble more than half of them. (But then again I buy low quality units which can be expected to have all sorts of problems.) I clean corrosion and bend contacts back into position in the jacks. Bypassing the equalizer is as simple as shorting the Rin and Rout contacts, and/or Lin and Lout. Bypassing the Dolby circuitry would be similar. Some of these players have a separate Dolby board, which makes bypassing it easier. If not, you'd need a circuit diagram to find the right contacts.
Checked potentionmeters and EQ (as far as my abilities go), seem ok. I also made a recording test and surprisingly both do record audio via wire. To shorten things I consider swapping the PCB from the player with the damaged ribbon cable to the other with no audio output. Bad thing is that I do not have an adequate solder tip on my soldering iron. Got to ask some friends for help on this task.
Swapping PCB did the job. Functional again. Nevertheless, volume is very low, especially in comparison to my DD-22/33s. Anyway thanks for your help.
A half decent soldering iron is so inexpensive I feel like an idiot for not buying one sooner. Your diagram is the main power amplifier. It has the voltages noted for the pins on the ic. You could check them against ground to see if any seem strange.
I'm also currently working on a J9 with no sound output. This was bought and heavily used as a donor unit. It was extensively corroded, missing parts and in bad cosmetic condition. The tuner has corrosion visible inside it, and probably many other moving parts do too. I expected it to be difficult to refurbish. I got the power led to light up and got the tape drive working. Bypassing the equalizer and Dolby sections, and replacing the volume control have not restored audio. I'd like to buy just a main board for it, but they never come up for sale. And it has to be a J9 board because it's different from the J09 and J600. I'm at the point of experimenting with using vinegar to dissolve corrosion. Then I got the idea of using audio signals from a known-good player. I could feed audio from the tape section and/or the radio section into the problem unit at various points, such as Rout (Right channel output) at the equalizer on the good unit, to Rout on the bad unit. To see if I can narrow down where the problem is. I haven't heard of people troubleshooting in this manner, so I don't know if it makes sense. I know both units will have to be powered, and presumably they have to be grounded together.
