Skip find sharp gf9191!

[Xander]

Still can't seem to get it going properly, anyone help me as to how I remove this board so I can take off the potentiometers?
Got the 4 screws out but appears to be held in by some primitive kind of ribbon wiring at the back (circled in red)
Thanks in advance

 

[Northerner]

Is it not attached at right angles to the other board? I've taken this board out before and replaced sliders. Just can't remember how lol

 

[Xander]

I thought this, do I need to take the main board out? Or any of the other hubbins or just pull that one board?? I do know know I'll look better soon, perhaps some more pictures will jog your memory?? Lol

 

[snedboy]

What a great find. I remember the fine tuning not seeming to work on one of my boxes until I switched to AM frequencies then you could hear the static change with the fine tuner

 

[floyd]

Fine tuning usually only works on sw and or am.

 

[Xander]

This makes sense, even more so now iv got the main board etc out and can see its mechanically sound.

Managed to get a little further tonight, get the soldering iron out tomorrow and take the vol potentiometers off for a good cleaning along with the rest of the unit.

 

[Xander]

Photos so far, it's pretty grimey so I'll get the rest stripped and get it clean to start with.

 

[Reli]

Try shining a flashlight in the sliders to find the actual contact points. You might need to use a paper clip with a piece of cloth to apply the solution.

 

[Northerner]

Get the front and back case (remove the transformer!) in a hot soapy bath!!!

 

[Xander]

I have already looked this is why initially I thought they had a dead/burnt spot because I can actually see it on the carbon rail, on both like there's no carbon anymore, so they may well be shagged. Which is why I was hoping they could be changed with record level sliders.

Will do! Get a tooth brush out for scrubbing also.

 

[Northerner]

The record level sliders might not have the same resistance. Would need to check it first

 

[Xander]

What a slag.. I did hear this off a tv repair guy I know (obv retired now who fixes TVs these days? Lol) but he did say if I'm up for a challenge I could swap the boards over (as long as they fit which it looks like they do) as it's mostly in the board.

Would have to remove the rivets from the slider to realise the board on both then "simply" swap them and redo everything iv undone so to speak

Anyways been cleaning tonight so pictures later! I'm a photo whore.. lol

 

[Xander]

So iv had a good go at it but still not right, getting some odd things going on.. I'll try to post a video so you can see what's happening but I think there is an issue with some switches somewhere.

Only got rh speaker in stereo mode but both in stereo wide and mono but rh is locked @ half volume (lowest it will go and does go up slightly after half way on the slider) lh is on at the bottom of the slider but dosent increase volume till half what up the slider, only does this in stereo wide and mono. In stereo only rh works with described fault, iv had the potentiometer off cleaned and re soldered.

What else could it be?

 

[floyd]

Clean/ check the external speaker switch on the back . these switches get dirty and lose contact.

 

[Xander]

The only switch on the back is the best cancel, it does have jacks for external speakers on the back will have a look at those.

The only parts I haven't actually cleaned are the circuit boards because A: I'm not exactly sure how to and B: taking some stuff of the gibbons off I think may be beyond my skill level ATM.

 

[Xander]

Had a good go at the external speaker jacks etc which did help clear sound up slightly but I think the underlying issue is the mode switch.

It's started really playing up now sometimes no sound at all in any mode the comes back, on an off while in stereo wide and still no lh channel in stereo.

 

[Reli]

The mode switch is a common flaw on Sharp GF-9___ series radios

 

[Xander]

Replacement needed? Can it be cleaned/reconditioned? Any help is at all is appreciated

 

[Xander]

Progress report: So the box has had a very good clean looks 10x better now. FM stereo light still non op but I'm sure that's to do with the function/mode switch, and the apps light for reverse is also in op.

Still having some issue with getting sound out of both channels in various modes but again the problem
Is the switch so I'll be having that off soon for a good clean. Bar that all working nicely now.

I have made repair work to the rear casing damage but not all of it, haven't sorted the distortion from the heat damage yet but will do that when I strip it again to look at the switch, also found some spare time today to make an antenna.

Photos for your viewing pleasure.

Photos

 

[Xander]

Been a little while but the box is still very much in mind, I need the holiday season to pass so I have coin to get the required parts.

Will be taking the function/mode switch off in the next few days see if it can be refurbed, also taking off the potentiometer board to have a go at the issue I have with the connections to the main board hopefully this will fix most issues bar that I'll be waiting for replacement parts.

I have made a slight bo bo trying to fix the rear casing damage, generally was looking much better then I went a little too far and it's opened up a crack... a lot looks a right mess now.

I should have made the crack strong before I hit it with the heat it's not terrible iv seen worse and I could easlily repair it but it would require painting the casing.