Hi, Happy new year for everyone! Maybe someone have aiwa hs rx705 service manual? i am a bit stuck in repair process sine one of smd components was damaged due to caps electrolyte and i do not know its value and because of that in reverse play mode device sometimes switches head to fwd play and device start to play music in backward.... Thanks in advance
Hello @Nokeshas , Welcome here! Did you see this thread: https://stereo2go.com/forums/thread...aps-belt-and-bad-phones-jack-connection.6372/ It might help. Kind regards, Emiel
Hi, yes i have seen this, but damaged part is not capacitor its resistor in the back near 47uf cap and transistor.
Please share some pictures with the PCB, as we might be able to help you without the service manual. If the unit uses off-the-shelf ICs (which the majority of walkmans do), there are datasheets available which show typical application schematics. EDIT: You have the datasheet of the BA3513 pre-power amp attached. The typical application schematic is at page 5. Also, there must be one mechanical switch that drives the switches inside the preamp. Is this switch clean, does it make proper contact ?
Hi, sorry but I would like to point out that even in the tred indicated by @Emiel there is a photo where you can see that resistance that you indicate and no value can be read there either... are you sure that the problem you encountered depends on that resistance??
yes, because it’s borrowed photo, on my board it just gone with a wind… if i just would know resistance… i think that because of that resistor is missing i got that anomaly: because of that in reverse play mode device sometimes switches head to fwd play and device start to play music in backward....
No rx797 is different device. i have found sm for rx705 there: https://remont-aud.net/load/audio/aiwa/aiwa_hs_rx705/42-1-0-66744 but i do not have account or understand Russian language.
I suggest looking at the datasheet of BA3513 I provided (specifically the schematic at page 5) and see if that resistor is part of the head switching circuit. To me it seems more likely the problem is somewhere else and would pay particular attention to the mechanical switch. Even though the actual head switching is done inside the preamp, there is a mechanical switch that tells the amp in which position the mechanism is in (FWD or REV). Given the intermittent nature of the problem, I would suspect this switch. And that should be cleaned anyway for good measure. For reference, it's typical for SMD resistors smaller than 1206 package to have no markings.
Well huge thanks for tip. i have checked again pcb and found that i totally forgot that it have that fw rw switch. Cleaned it and now not noticed that anomaly anymore Thank you and also for other members that wanted to help. P.s. instead of leaving that "place"without resistor i have solderend in 10k one. Just got manual and it shoul be 220k
