Hi guys, I've been lurking a while and now finally have a cool old Boombox of my own which  gives me a reason to post.

First off, hello to all of you!
I recently purchased an old Sharp GF-888 and have a few questions..

1. When adjusting the volume knob, there's a static/crackling/whateveryouwannacallit sound. It goes away as soon as I leave it alone.. What causes this? It's not super important just kinda annoying.
Buying contact cleaner to see if problem goes away.

2. Again, something minor but the light that illuminates the radio AM/FM slider area is burned out. Where is the usual location for it and with what type of bulb do you replace with?
Doesn't look like there even was a bulb there; I'll take a closer look

3. The bass adjuster only seems to be working very slightly.. from -5 to +5 isn't much of a difference.
Buying contact cleaner to see if problem goes away.

 
4. *SOLVED*
This one is my main concern as I would like to have my iPod hooked up to this..
There is a selection switch for the radio/tape/aux which doesn't seem to want to switch over to tape or aux.. it just stays on radio, however it does do something because the radio volume goes quiet when on tape position and louder when on aux position. What would cause that?? I'm pretty good with my hands and have already split it in half but I don't wanna start messing with anything before getting some pro advice.
This one kinda fixed itself, maybe corrosion problem? This selector switch works like it's supposed but only when the "Microphone Volume" slider is all the way down. As you turn it up though, the FM radio starts coming in at the same time as whatever is playing on aux.

5. The first cassette deck, unless i have the pause button clicked down, will continuously click.. kinda sounds like the auto-reverse.
Will report back after changing out the belts.

 
6. The On/Off switch doesn't work; only stays on.
This now works when the tape deck assembly is disconnected. Possibly due to the belts being worn out. We'll see what happens after belts are changed.


I can take pictures of anything, just let me know.

Anyway here it is, heavy as all hell too

Welocme aboard.

1. sometimes sliders/pots become oxidised over time and need cleaning. The way to do this is to carefully spray some contact cleaner into them a little at a time and manually operate the slider/knob with your fingers. Do this while powered off. You can get contact/switch cleaner from Maplin in the UK.

2. This is box specific. You will need to go inside and check the current type of bulb and replace it like for like. It might actually be something else and not the bulb that is causing it to be dim, in this case you are going to need the schematic and check componenets that are used for lighting that bulb.

3. This could be anything, once again though give it a good cleaning with contact cleaner.

4. Contact clean that switch thoroughly and you might find it starts working ok after a good spray.

5. Sounds like the belts have gone on that deck. Belts are relatively easy to replace and you can source them at CPC online. Do both decks at the same time though.

Thanks for the quick reply! I'll get some contact cleaner and try to fix those few issues..
As for the belts, I  took a picture which I'll post up in a bit showing the whole area. I can see one is connected (to the number 2 deck) but I see nothing with the number 1 and can't figure out where it would go to..

Generally you look for the motor and you will find a flat belt attached to it. There are usually one or two other smaller belts too, sometimes you have to get right into the deck section to see them and you will absolutely need to do that to replace them.

Thanks for your help guys, I've got some things figured out and some new problems as well.. Here's a picture I took of the tape player assembly:

http://i42.tinypic.com/2zocgf6.jpg

I'm going to be updating my original post as things progress.
Thanks again so far!

Hi and welcome here,

judging on the this quote from your picture, it looks like the power switch is broken, it's very common problem for boxes 555 - 888 series, those switches are way too fragile, and have a limited lifespan.

This is more than likely it then as the main power switch doesn't do anything, the unit it always powered on. So I assume replacement is the only option or can it be repaired?

Also, anybody know what year this Box is from? Just curious..

Forget the power switch.  If you deck is making a clicking noise all the time, it is stuck in the play mode which happens when the belt broke during a play cycle.  You will need to do a proper reset of that mechanism in order to turn it off.  That's why the machine is on all the time.  If the power switch was broken, it's more likely that it stays off all the time.  When the deck is in the play mode (which is why you continuously hear the clicking), the deck microswitch powers up the entire boombox regardless of mode.  Not saying your power switch is definitely OK.  But what I am saying is that if your deck is not reset, it will definitely cause your machine to be always ON.

As for the radio working in AUX mode -- if this is a Japanese boombox, they love to do the karaoke thing and many of their boomboxes have a "radio-mixing" function.  There is probably a FM/FM-mixing control somewhere that turns mixing on/off.  Of course as you've discovered, if you have it ON, you can also turn down the mixing level to reduce the FM contribution but it's best if you just figure out which switch and turn it off.

don't forget the power switch, if you wanna get this unit back to the working order.

if the main power switch is broken on this model, then if you wanna turn the radio or aux on - you have to push play button of the tape deck.
there is a chance, the previous owner just shorted the micro switch - just to listen to the radio, or there are more than one broken microswitches - that's the reason why the motor is always spinning, and mode selector doesn't work properly.

the box was made in 80-81

the serial number at the back plate, contains the production date,
first digit is the year, two followings - the month.

most likely the first digit is "1" - it means it was made in 1981.

Awesome info in here! I just started my day so I'm going to jump back inside this thing soon.

Stormin Normin: What you say makes sense.. So how do I go about doing that deck reset you mentioned? I'm going to be checking the power switch too though so at least that could be crossed off the list.
It is a Japanese Boombox so I should have known about the karaoke deal hahah thay LOVE it here. I've got that slider all the way down now with nothing mixing in so I think that's solved.

metad: I'll be testing the power switch and check the microswitches for the A deck and hopefully figure out what's causing this. I've seemed to have figured out the mode selector problem so at least that's out of the way.
And I checked the back.. 10331899 so then it's March 81 it looks like, sweet.

Alright so if I get deck A to stop continuously playing and if it doesn't power on anymore then it's safe to assume the problem is with the main power switch then, correct?

New developments!
So today I had a few hours to dive into this thing a little more and see what's going on.. The pics are kinda big so I'll just be posting links.

Ok so after a good half hour I finally was able to remove the entire tape player assembly.
http://i40.tinypic.com/33tm3qq.jpg

First thing I did was to look at the back and check the belt situation.
http://i41.tinypic.com/6swhsn.jpg
http://i43.tinypic.com/mjmic4.jpg

I will replace them eventually but for the time being they're ok, enough to not cause the continuous playing issue.
The next thing I did was to start plugging things in one by one trying to eliminate possibilities. So now I've narrowed it down a bit as you can see in this next pic:

http://i44.tinypic.com/1zz42kk.jpg

I've temporary put it all back together with the large connector unplugged (I'm going to be taking it to the park this weekend) but I would love to everything working the way it should. Right now I don't have use of the tape decks but at least I have the on/off switch working.
This whole thing of having power to the tape deck motor causing the box to not be able to turn off makes me think the problem is a short somewhere, but I'm not sure.

Anyway that's all I got...

here is the service manual for GF-555

http://REPLACEMENT ERROR/fileS...3/SHARPGF-555H-E.PDF

they are similar models, with differences in the radio and preamp sections, but the tape mechanism and power amp are the same, so you can trace why the power is always comes to motors.

if the clicking noise comes from solenoid, you have to check APLD-search circuit also.

Most of which are likely to be solved with my info. Thanks and gl.

I think you may be over-thinking this.  The belts might not be snapped but that doesn't mean they are OK.  Unless you are saying that all functions are working like they are supposed to....  play, RW, FF, strong, without slippage.  The reason is that the belts might still be present but have lost enough friction and or tension for proper operation.  The sharps also have another known issue with an idler pulley tire turning to goo.  But that will result in play issues and not the always on, clicking noise.  I can even see in your pic, the whitish residue near the middle of the belt -- to me, those belts look worn.  As for plugging and unplugging the connectors -- that really doesn't tell you much since you don't know what the plugs are for, or what are their purpose.  That's like looking under the hood of your car and randomly unplugging things...  Look, the engine doesn't start anymore if I unplug this or that, but if I leave the bigger connector in......  see what I mean?  What is the connector, what is it's purpose, what does it go to...  if you know none of that, then stop unplugging things.... on a virgin unmolested boombox, rarely are connectors like that ever a cause for any issues.

What I can tell you is this:  I have had, and still own several examples of these sharps and when they need rebelting, the decks always run continuously and make a periodic clicking noise.  Each time I encountered one of these with this problem, servicing the deck including full rebelting resolved the issues.

I still say, start with a proper rebelting and go from there.  It's the cause, 95% of the time, for the symptoms you describe.

Ok I'm convinced, I'll change the belts before doing anything else haha.
So do they stretch out over time? So if I measure the ones on there currently I have to subtract a few millimeters?

And metad that link you put up for the manual doesn't seem to working for me..

Thanks everyone for the help so far

manual is here

index.php?board_oid=193392314111653483&content_oid=263906035085199338

Hi ACS and welcome to S2Go

If you box is indeed identical to the GF-555 you'll need the correct belts. They do stretch over time and it can exceed 15% of their original size.

Here's the correct belts you need

FRW 8.5

SCQ 6.7

SCX 8.0

Just find a local dealer and give them these and you should be back in business in no time!

Nice looking box, but why aren't the speakers aligned with the speaker trim?

metad: link works now!

Brutus442: thanks for the info! I'll look into finding an old electronics shop and see what they can do..

Reli: I noticed this too once I got it out into some light and it actually bugs me too! When I had it apart though I checked it out and it looks like there might be come clearance issues if the speakers were moved outward to line up with the rings.. but then again why didn't they just make the rings line up with the speakers then? Design fault maybe?