Translate this page:

Hello, Last week I picked up a nice Kenwood KA-3500 40watt intergrated amplifier in pretty good shape. Upon using it a bit more, I noticed a bit of distortion at high volume, more so in the left channel. I checked the DC offset at the speaker terminals, and the L channel said 100 mV, while the R was 25 mV. I understand this isn't so good for the L channel at least, but unfortunately this amp doesn't have any DC offset adjustments. Am I right in saying that to fix this I'd have to replace the output transistors? -- On a related issue, in the service manual I found the section on BIAS adjustment, and I read online how it can affect the DC offset. So I hooked up my voltmeter to the test points, and I got 4 mV on the L, and 8 mV on the R. In the manual it says should be 40 mV.....(!). Is there something wrong here? I tried carefully adjusting them, but they only go to 30mV with the pots fully on, this doesn't seem right to me. -- I compromised at 20 mV BIAS for both channels, and now the DC offset is 50 mV for L, and 5 mV for R, which is better, less than half what they were. I'm wondering, will I damage anything doing this, should I put them back to where they were? -- The service manual is on site here. Let me know if you want me to upload an english copy of the Owner's Manual, it has a better schematic in it all on one page, easier to read. I've also included some pictures. They're not my actual unit, but mine is exactly the same, but less dusty. -- Thanks for reading this. Many thanks in advance, and have a peaceful Palm Sunday! :taps2: Bellarmine

Hello,

I recently purchased a used Kenwood M-9000 SS micro Hi-Fi system, but unfortunately, the unit is not functioning correctly. When I power it on, the display is stuck on the message "Waiting for PC Wizard", and the device becomes completely unresponsive – it does not react to any buttons or remote control inputs.

From my research, it seems that this issue may be caused by a missing or corrupted firmware, particularly related to the Sunplus SPHE8202 chipset used inside the device.

I have been trying to locate the correct firmware file (possibly DVDROM.BIN) that matches the hardware (the board ID may be BD305890BB9B50), but so far, I have had no luck finding a working download source.

Could someone please help me with:

• The correct firmware file for this model

• Instructions or guidance on how to recover the system using a USB flash drive

• Any experience with solving this "Waiting for PC Wizard" message on similar Sunplus-based systems

Any help or direction would be greatly appreciated!

Thank you in advance.

Best regards,
Dejan Todorović

Hello Mindekinek!  Törötten kaptam ezt az erősítőt  és szerettem volna direktben járatni a végfokokat. Szóval csak a végpanel és a trafó maradt meg. A gond az hogy erősen sistereg mintha összeszedne nem kis zajt. Kötöttem már így végeket de ez kifogott rajtam. Letesteltem amit kell, minden feszültség érték megegyezik a manualban lévővel. Aki tapasztalt már ilyet kérem ossza meg velem hogyan oldotta meg. Előre is köszönöm.

Sziasztok! Nem tudom mi lehet a gond az erősítő 5csatornás equaliserével.2 db M5227p ic vel van felépítve.Bekapcsolt EQ állapotban az erőlködő egyáltalán nem szól,kikapcsolt(defeat)állásban meg szabályoz(lefelé) az adott EQ frekvenciákon a potit felhúzva gerjed egy szint után.Rajz kellene mert így elég áttekinthetetlen a jel útja.Hanggenerátorral próbáltam követni de már kissé belefáradtam. Üdv!