SL-HF950 Problems and Repair (Aus) - UK Vintage Radio Repair and Restoration Discussion Forum

WoesOfTheBeta · 30th Jan 2017, 6:51 am

Hello again! The last time I was here you all helped a lot in repairing my VTC-9300PN, for which I am very grateful. Now I return in the hopes I can repair my latest device, a SL-HF950.

I picked it up at my local tip (for the low price of free) after seeing it baking in the sun and caked in a layer of dust. By all accounts this is a steal, if the thing actually worked.

The tray opens and closes successfully (which is pretty cool for a damn millennial like me). The tape ejection mechanism works... kinda. It likes to growl at me a lot on the second ejection (it must be very hungry). The playback feature is completely rooted, as it can only play 3 seconds at a snail's pace before giving up. And FF/RW only goes up 20s or so before stopping too. All of these problems are shown on video here (if the filename looks sketchy, know that the site does this to all files).

Hopefully this is just a belt problem again. I'm not too keen this time to mess around with electrical components on a machine this densely packed. As always, any help would be appreciated.

Grubhead · 30th Jan 2017, 2:05 pm

I would start by having a good look around the mechanism. Get the bottom cover off and see if there are any broken plastic parts.
You might have to be careful of the tape too, if you watch the video the bottom edge looks a bit wobbly.

paulsherwin · 30th Jan 2017, 2:40 pm

You may find it's full of dust and dirt too.

Vauxfan2k · 30th Jan 2017, 7:36 pm

I'd be more worried about anything living or dead in it lol funnel web spider nest :/

8 Tracker · 30th Jan 2017, 8:49 pm

The head's not rotating, that's causing the premature shutdown. The heads should rotate during all transport functions (Play, FF, Rew). Give the top disc a gentle push with your fingers to see if it's free. If it is, chances are it's the speed sensor that's at fault. It's a bit of a fiddly change IF you can find a spare, but would probably bring the machine back to life.

The delay on the carriage closing could be a split on one of the loading gears. It can then spin on the shaft. Mine suffered from this. I managed to glue it back on to the shaft and so far it has held.

Well done on finding one of these rare beasts. Superb machines, excellent picture.

Mark.

WoesOfTheBeta · 1st Feb 2017, 4:41 am

Hello everyone.

I've taken the back off and exposed the loading gears and shaft. I've documented the playing behaviour again, video link here.

I appreciate your responses, however I must point out that I am a novice in these vintage repairs and will most likely need some sort of guidance (i.e. identifying & disassembling the right part) to 'get it right'.

Quote:

Originally Posted by 8 Tracker

Give the top disc a gentle push with your fingers to see if it's free. If it is, chances are it's the speed sensor that's at fault. It's a bit of a fiddly change IF you can find a spare, but would probably bring the machine back to life.

If you mean the leftmost disc in the video, then yes it is freely spinning when touched.

Quote:

Originally Posted by 8 Tracker

The delay on the carriage closing could be a split on one of the loading gears. It can then spin on the shaft. Mine suffered from this. I managed to glue it back on to the shaft and so far it has held.

This would probably involve removing the cassette compartment, right? I had a cursory look at the service manual and it was the first that came up in disassembly.

Sanbeta · 2nd Feb 2017, 3:35 pm

On the left motor when play is pressed and the play light illuminated ONLY try to turn the top or bottom of the head disc. If you feel resistance then it's the hall effect sensor. (Your's does look like it has the conductive glue still on the four pins.It's the sensor located inside the white box on the rear of the head motor in your video ).It's a common issue after time. If you do not feel resistance with the play light lit ONLY then you have an IC issue or maybe dry joint.

Sanbeta · 11th Feb 2017, 1:00 pm

I've just watched your video of the 950.
If you try what I've mentioned above when the play light is lit then it should highlight if the hall sensor is the reason the head disc does not spin.

The slight delay in going back down with motor overun...................
Could be a split gear but also the mode switch has been known to come loose. Usually this causes a banging /clicking sound when the hatch pops up until it goes down again on it's own. It could be this has moved out of kilter.

Either issue can both be sorted but if you've never done this can be fiddly to do.

.....Kevin

dj_fivos_sak · 11th Feb 2017, 7:17 pm

Just what Kevin said. The hall effect sensor was a common failure in these machines. It has an orange glue that when it dries out, it becomes conductive and shorts out the sensor. The sensor is located at the bottom of the drum motor. Try scraping off the glue and see if the problem is solved. Grab the service manual here:
http://freeservicemanuals.info/en/se...50ES/SLHF950E/

Also, watch this amazing repair video:
https://www.youtube.com/watch?v=vt2MO1ScbPM

Fivos

30th Jan 2017, 6:51 am	#1
WoesOfTheBeta Retired Dormant Member Join Date: Dec 2016 Location: Wollongong, New South Wales, Australia. Posts: 6	SL-HF950 Problems and Repair (Aus) Hello again! The last time I was here you all helped a lot in repairing my VTC-9300PN, for which I am very grateful. Now I return in the hopes I can repair my latest device, a SL-HF950. I picked it up at my local tip (for the low price of free) after seeing it baking in the sun and caked in a layer of dust. By all accounts this is a steal, if the thing actually worked. The tray opens and closes successfully (which is pretty cool for a damn millennial like me). The tape ejection mechanism works... kinda. It likes to growl at me a lot on the second ejection (it must be very hungry). The playback feature is completely rooted, as it can only play 3 seconds at a snail's pace before giving up. And FF/RW only goes up 20s or so before stopping too. All of these problems are shown on video here (if the filename looks sketchy, know that the site does this to all files). Hopefully this is just a belt problem again. I'm not too keen this time to mess around with electrical components on a machine this densely packed. As always, any help would be appreciated.

30th Jan 2017, 2:05 pm	#2
Grubhead Heptode Join Date: Dec 2016 Location: Sheffield, South Yorkshire, UK. Posts: 539	Re: SL-HF950 Problems and Repair (Aus) I would start by having a good look around the mechanism. Get the bottom cover off and see if there are any broken plastic parts. You might have to be careful of the tape too, if you watch the video the bottom edge looks a bit wobbly.

30th Jan 2017, 2:40 pm	#3
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,975	Re: SL-HF950 Problems and Repair (Aus) You may find it's full of dust and dirt too.

30th Jan 2017, 7:36 pm	#4
Vauxfan2k Hexode Join Date: Aug 2016 Location: Inverness, Highland, UK. Posts: 300	Re: SL-HF950 Problems and Repair (Aus) I'd be more worried about anything living or dead in it lol funnel web spider nest :/

30th Jan 2017, 8:49 pm	#5
8 Tracker Hexode Join Date: Jul 2009 Location: Mablethorpe, Lincolnshire, UK. Posts: 286	Re: SL-HF950 Problems and Repair (Aus) The head's not rotating, that's causing the premature shutdown. The heads should rotate during all transport functions (Play, FF, Rew). Give the top disc a gentle push with your fingers to see if it's free. If it is, chances are it's the speed sensor that's at fault. It's a bit of a fiddly change IF you can find a spare, but would probably bring the machine back to life. The delay on the carriage closing could be a split on one of the loading gears. It can then spin on the shaft. Mine suffered from this. I managed to glue it back on to the shaft and so far it has held. Well done on finding one of these rare beasts. Superb machines, excellent picture. Mark.

2nd Feb 2017, 3:35 pm	#7
Sanbeta Hexode Join Date: Feb 2012 Location: Lowestoft, Suffolk, UK. Posts: 256	Re: SL-HF950 Problems and Repair (Aus) On the left motor when play is pressed and the play light illuminated ONLY try to turn the top or bottom of the head disc. If you feel resistance then it's the hall effect sensor. (Your's does look like it has the conductive glue still on the four pins.It's the sensor located inside the white box on the rear of the head motor in your video ).It's a common issue after time. If you do not feel resistance with the play light lit ONLY then you have an IC issue or maybe dry joint.

11th Feb 2017, 1:00 pm	#8
Sanbeta Hexode Join Date: Feb 2012 Location: Lowestoft, Suffolk, UK. Posts: 256	Re: SL-HF950 Problems and Repair (Aus) I've just watched your video of the 950. If you try what I've mentioned above when the play light is lit then it should highlight if the hall sensor is the reason the head disc does not spin. The slight delay in going back down with motor overun................... Could be a split gear but also the mode switch has been known to come loose. Usually this causes a banging /clicking sound when the hatch pops up until it goes down again on it's own. It could be this has moved out of kilter. Either issue can both be sorted but if you've never done this can be fiddly to do. .....Kevin

11th Feb 2017, 7:17 pm	#9
dj_fivos_sak Heptode Join Date: Mar 2015 Location: Lefkada, Greece Posts: 969	Re: SL-HF950 Problems and Repair (Aus) Just what Kevin said. The hall effect sensor was a common failure in these machines. It has an orange glue that when it dries out, it becomes conductive and shorts out the sensor. The sensor is located at the bottom of the drum motor. Try scraping off the glue and see if the problem is solved. Grab the service manual here: http://freeservicemanuals.info/en/se...50ES/SLHF950E/ Also, watch this amazing repair video: https://www.youtube.com/watch?v=vt2MO1ScbPM Fivos