Hi my name is Hans and i was invited by bone yard. I was posting on audio karma with no real interest or traction beyond one post. I am currently trying to hunt down a low hum from the left channel in my Sanyo M9930 boombox that mostly runs well. I will try to make a post about it in tech talk once I’m allowed to. It is currently in a state of… many pieces.
Welcome to the forum, we have a lot of members that slide between the websites. Good luck with the hum, one of my newer units had it, after a few days of hitting the piano keys (on the deck) I cleaned it up but you might have to take it apart for a proper cleaning and hopefully it's mechanical not electronics.
Thoroughly clean the recording bar switch and clean all your grounds both sides of where the points touch for going ground to ground like it going across tape deck. You're normally two wires going to and from the tape deck and you need to wire brush or sandpaper or whatever you use to clean both sides of those wires and all your other ground points. Clean all the points. Clean the recording bar switch with the accent work the switch the oxet work the switch. The accent worked. The switch stupid phone won't spell. Deoxit, here you go. Stupid voice speak phone. Basically follow the sound from the source through every switch and connection to ensure everything is clean and you shouldn't have any hum so you have to think about that. How many sources are there? How many switches? Other things that sound goes through from the beginning to coming out your speakers or headphones or whatever. Yes, the headphone connection can be bad. Corroded the speaker connections can be corroded that'll give you a hum believe it or not a 9930 Sanyo I had one. I had a 99 40 Sanyo which is similar to the 9930. I had both of those and I shipped them all off to California. I might still have one of those I'm not sure, but I've definitely worked on my share of samyos. I still have a lot of sanyo's here actually in the tech talk in here. I'm working on yet another m7850k Sanyo. Hope to finish it tomorrow. I can rattle on there you go
Yes, it's a very basic boombox volume tone, radio cassette. Nothing special, just it can record and no line in. Sounds very nice. Once it's working it's only I think a six battery 9 volt operation 2. Watts per channel output power. Very heavy. Very durable. The only issue with this is that when the motor goes bad you have to replace the motor because the motor has the internal speed control that is not adjustable from the outside, it sets from the factory and that's it.
The few Sanyo's I have are similar, the fact they've lasted so long is a good sign but they won't win any beauty awards.
No it does not have line in. It may have RCA jacks on the side panel but they are not line in because there is no selector switch to switch to line in on the radio. Therefore the RCA jacks if it has it is only and I repeat only for recording. If your model has the RCA jacks in and out, it's only for recording the way to access that is to plug in your source and then hit record on the cassette and then you can hear your source only through and when the cassette player recorder is working.
All old Sanyo boombox owner's this is a Must watch video! The GOVERNATOR - How vintage DC tape recorder motors work! All
