This thread covers the repair of WM-DD series (WM-DD, WM-DDII, WM-DDIII, WM-DD30, WM-DD33, WM-D3, WM-DD100, WM-DC2) takeup reel support repair....
There are 2 options: disassemble the button and clean manually or simply spray some contact cleaner over and pressing the button many times. The...
Given the buttons use a resistor ladder, any increased resistance on the buttons will render this behavior. Solution is to clean the buttons...
Looks to be a 9 x 7 x 1.5mm (OD x H x pin diameter), which is pretty standard for many of these early walkmans. But it's best to double check with...
It is recommended to do a full service on these DD9s. A tutorial will come in that regard. Pulleys are held by cut washers that are hidden...
The 2 x 470uF capacitors are for mains hum filtering if an AC adapter is used. Not related to your problem at all. Also, it's important to use low...
The controller would not be affected by changing the position of the walkman. When these jumps in speed happen, what happens to the motor voltage...
According to the table atatched, DIN reference level (250nWb/m) is 1.3dB higher (or 1.4dB higher if I take their +2.8dB on Dolby, I used +2.7dB in...
Would be worth measuring these under load too, to see the difference. As it has been mentioned before, these unregulated AC adapters have...
Yes it does look like a mechanical problem, what's curious is how it gets triggered only in record mode. A hard to turn roller can increase the...
Interesting. Now I fully understand something that have missed before, the motor is actually struggling not having enough torque at the end of...
There's nothing obvious so far, the voltage drop in REC is normal given there's more current draw in this mode. I would assume you don't have an...
It's an LA5524, seen this IC in a couple of other walkmans although not the most common. I think the drive transistor is also integrated into the...
There is no risk in measuring these 2 voltage rails. You don't need to touch the CX20084 to do these measurements. See picture attached for...
If RV601 doesn't change the speed with solder bridge open, that indicates a fault inside the CX20084. Assuming that's the case, there's nothing...
Yes, the regulation circuitry is on the motor board. Seen that before motor + servo being treated as a single unit by the service manual. One...
Yes, 3kHz is good enough for speed ajustments. At a higher frequency, despite there is more resolution available there's also more variation. In...
Interesting. There is no abnormal mechanical sound without a tape. With FixYourAudio test tape W&F is jumping quite a bit, with peaks reaching...
Yes that is correct, higher frequencies have a smaller "footprint", that's the reason head azimuth and tape path alignment in general affect the...
Yes your guess is correct the auto-off circuit seems fine no need to check those 2 caps. The voltage at pin 9 rises the same as before, right ?...
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