Hi guys again from the new forum.I just opened a sharp 9494 for the first time. I have a funny issue with bass and tremble they do not respond at all where volume is working just fine tomorrow since i am a rookie i am going to get a phillips red spray as told by a friend of mine any other suggestions would be helpfull I mean how to check the armored box or whats its called and so on Thanks on any advice on this modell!
I am asking for the experienced members on this particulate boombox if they encountered a similar problem and how they fix it! Please note i am not a technician or close to that so keep it simple as much as you can!
Do you think that, maybe, the contacts inside the sliders have let go? I've never worked on the 9494, but I've had to rebuild sliders on my M70 and a GF-9000 for a friend. It's not that uncommon.
Could be i am starting collecting material for my bench in order and with help to be able to fix minor issues.I ll give it a try tonight with spray cleaning and see if that does not work what to do next.
Another issue i am having with this box is that i hear cracking sounds from the cassete especially on higher volumes something like vibration from the cassete "glass" cover any suggestions?
This is gonna be a long post. WARNING: If you've never done this, it is highly recommended that you practice on a junk slider from another unit. I'd hate to see a unit as nice as a 9494 become a parts unit over a couple of sliders. Here's how you do it: You'll need to remove the sliders from the board to do this. You should carefully mark their positions and orientation on the board before removing them. And take lots of pics. Once you get the sliders off the board, you should check for continuity (with a meter) between the carbon traces and the contact sides of the sliders. If you have no continuity, chances are that the contacts have let go from the sliders. If you do have continuity, you'll want to check the resistance while working the slider. As you move the slider from the max. position to the min. position, you should see the resistance increase. If the slider checks out, the problem is likely elsewhere and you shouldn't bother trying to open it (they're not designed to be taken apart) until you can completely confirm there is a problem with the slider. If you've determined the problem is the slider, then it's likely the contact that rides on the bottom of the trolley (the moving part of the slider) has let go. Only work on one at a time so you don't mix up parts. Before you're ready to open it up, you should make a couple of witness marks on the slider so that it goes back together the same way it came apart. Once you've marked it, turn it over so you're looking at the underside. Make sure your work area is clean and organized, and you should have a soft cloth or piece of leather on your work surface to prevent things from bouncing and rolling. These parts are very tiny and are easily lost forever when they get out of your sight. You'll see that the metal housing has tiny tabs that hold the contact side of the slider tight to the trolley and housing (it looks like a small, skinny board). While holding the slider "sandwich" together, very carefully unbend the tabs to free the contact board. Very slowly and carefully coax the contact board away from the housing while working close to the work surface. Take note of any springs and/or detent parts as you open the slider (like I said, these parts are tiny - And I mean tiny). You may find that the "feelers," which are the contacts that ride on the underside of the trolley, are loose inside the housing. That's how I've found them in the ones I've rebuilt. You'll need to determine how they originally sat on the trolley and figure out your left and right contacts. This is why it is so important to mark the slider before disassembly. The only thing I've found that works to re-attach the "feelers" to the trolley is a plastic super glue with a plastic activator, since the underside of the trolley is usually nylon. While the glue is setting up, this is a good time to lubricate the inside of the housing. I've used damping grease, which gives the slider nice buttery feel. I've also used all-purpose automotive grease, which gives it a more slippery feel. Either type will work - just keep the grease away from any electrical contact area. Now the glue should be set up and you can re-assemble the slider. You can check the slider with the meter again to see if the rebuild was successful. If you've determined success, you can solder the slider back to it's position on the board and it should function as intended. Unfortunately, my slider rebuild photos from way back were lost in a devastating hard drive crash, so you might want to do an image search to familiarize yourself with what you'll be up against. They are not designed to be serviced, so you don't get much more than one chance to get it right because the tabs that hold everything together will eventually fatigue and break. If that happens, you'll be better off looking for a new slider. There may even be a chance that the "feelers" are missing. I suppose you could try to make some, but it might require help from some magic elves. Tools You'll Need (besides the standard soldering and de-soldering tools): - PATIENCE - Attention to detail. - A couple of different colored fine-point permanent markers - A small, sharp flat-head screwdriver or soldering tool for lifting the tabs - Some precision needle-nose or flat pliers - A small artist brush to apply grease to the metal housing I know there's at least one other member here who has done this on many sliders. If he has anything to add, I'm sure he will.
I highly appreciate the time you spend writing this!I will follow instruction but i think i will do it together with a technician in order not to destroy the unit and maybe learn something new in the process!
