Pioneer CT-F 850 Cassette Deck Problem - UK Vintage Radio Repair and Restoration Discussion Forum

starone · 8th Jan 2017, 3:18 pm

Hello

Was hoping someone might be able to give me some advice with what's wrong with the above deck. Picked it up last week at the car boot for a fiver and really like the look of it. It all lights up and works to a degree, but after approx 2 seconds of either playback/fast forward/rewind the transport shuts itself off. If you hold your finger on any of the above buttons it continues to work but keeps clicking as if trying to shut off. I think the belts will need replacing at some point but I don't want to start dismantling it without having an idea of what's wrong, as it looks pretty complicated to say the least!

Martin

paulsherwin · 8th Jan 2017, 4:25 pm

It is very likely to need a new main capstan belt and possibly other belts. The first thing to do is to take the cover off and watch what the mechanism is doing when you try to play a tape.

Tom_I · 8th Jan 2017, 5:11 pm

It sounds like what's happening is that the auto stop mechanism is being triggered continuously. The sensor for this is a photo interrupter driven by a small belt from the take-up spool. It may just be that this belt has broken.

You can download a service manual for this cassette deck from Hifi Engine (click this link). You will need to register with the site first, if you haven't already.

julie_m · 8th Jan 2017, 5:13 pm

It's possible that the sensor which determines whether or not the tape is moving is driven by a belt which has stretched. This would cause the control logic to think the tape had pulled taut at the end of the side.

Pictures?

starone · 9th Jan 2017, 12:05 am

Thanks for that. I've just registered with hi fi engine and will download the instructions as suggested. I'll also get a few photos of it when I get the chance. The only other problem with this that I can see is the power cord has been cut to within an inch of the backplate. Can't believe someone has cut the cable and thrown this in the tip - I got it from one of the regular tip dealers at the local car boot. I suppose I'm lucky it's not damaged and missing bits like most of the stuff they sell.

Cheers
Martin

John123 · 9th Jan 2017, 1:54 am

Often the sensor is on the tape counter, so if the belt to the counter has perished the mechanism will switch off.

ben · 10th Jan 2017, 12:35 am

Change the counter belt/motion sense belt as suggested.
However, the spool motor in these decks suffers from dead spots. check the spooling in playback carefully.

starone · 8th Feb 2017, 12:12 am

Just an update on this: it was indeed the belt from the take up spool to the pulley that drives the tape counter that had perished. It drives another pulley that is mounted to a sensor for the auto stop. I confirmed this by temporarily hooking the large flat belt up over this pulley causing it to turn. The good news is it sounds really good and all the other functions seem to work. I've also fitted another power cable to replace the one that had been cut. The bad news however is that at 25 pounds for the belt kit it's probably going to have to wait a little while. I'd like this in my future set up, but for now I've boxed it up and put it in storage until I can justify the outlay. Thanks to everyone who helped me find the problem.

Martin

camtechman · 8th Feb 2017, 12:24 am

Yep, It's a known problem as you can read here:

http://www.tapeheads.net/showthread.php?t=21183

8th Jan 2017, 3:18 pm	#1
starone Triode Join Date: Feb 2016 Location: Nottingham, Notts. UK. Posts: 43	Pioneer CT-F 850 Cassette Deck Problem Hello Was hoping someone might be able to give me some advice with what's wrong with the above deck. Picked it up last week at the car boot for a fiver and really like the look of it. It all lights up and works to a degree, but after approx 2 seconds of either playback/fast forward/rewind the transport shuts itself off. If you hold your finger on any of the above buttons it continues to work but keeps clicking as if trying to shut off. I think the belts will need replacing at some point but I don't want to start dismantling it without having an idea of what's wrong, as it looks pretty complicated to say the least! Martin

8th Jan 2017, 4:25 pm	#2
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,943	Re: Pioneer CT-F 850 Cassette Deck Problem It is very likely to need a new main capstan belt and possibly other belts. The first thing to do is to take the cover off and watch what the mechanism is doing when you try to play a tape.

8th Jan 2017, 5:11 pm	#3
Tom_I Heptode Join Date: Jul 2006 Location: North Herts. UK. Posts: 549	Re: Pioneer CT-F 850 Cassette Deck Problem It sounds like what's happening is that the auto stop mechanism is being triggered continuously. The sensor for this is a photo interrupter driven by a small belt from the take-up spool. It may just be that this belt has broken. You can download a service manual for this cassette deck from Hifi Engine (click this link). You will need to register with the site first, if you haven't already.

8th Jan 2017, 5:13 pm	#4
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Pioneer CT-F 850 Cassette Deck Problem It's possible that the sensor which determines whether or not the tape is moving is driven by a belt which has stretched. This would cause the control logic to think the tape had pulled taut at the end of the side. Pictures? __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

9th Jan 2017, 12:05 am	#5
starone Triode Join Date: Feb 2016 Location: Nottingham, Notts. UK. Posts: 43	Re: Pioneer CT-F 850 Cassette Deck Problem Thanks for that. I've just registered with hi fi engine and will download the instructions as suggested. I'll also get a few photos of it when I get the chance. The only other problem with this that I can see is the power cord has been cut to within an inch of the backplate. Can't believe someone has cut the cable and thrown this in the tip - I got it from one of the regular tip dealers at the local car boot. I suppose I'm lucky it's not damaged and missing bits like most of the stuff they sell. Cheers Martin

9th Jan 2017, 1:54 am	#6
John123 Heptode Join Date: Jan 2007 Location: Luton, Bedfordshire, UK. Posts: 891	Re: Pioneer CT-F 850 Cassette Deck Problem Often the sensor is on the tape counter, so if the belt to the counter has perished the mechanism will switch off. __________________ Regards, John

10th Jan 2017, 12:35 am	#7
ben Dekatron Join Date: Aug 2006 Location: Madrid, Spain / Wirral, UK Posts: 7,498	Re: Pioneer CT-F 850 Cassette Deck Problem Change the counter belt/motion sense belt as suggested. However, the spool motor in these decks suffers from dead spots. check the spooling in playback carefully. __________________ Regards, Ben.

8th Feb 2017, 12:12 am	#8
starone Triode Join Date: Feb 2016 Location: Nottingham, Notts. UK. Posts: 43	Re: Pioneer CT-F 850 Cassette Deck Problem Just an update on this: it was indeed the belt from the take up spool to the pulley that drives the tape counter that had perished. It drives another pulley that is mounted to a sensor for the auto stop. I confirmed this by temporarily hooking the large flat belt up over this pulley causing it to turn. The good news is it sounds really good and all the other functions seem to work. I've also fitted another power cable to replace the one that had been cut. The bad news however is that at 25 pounds for the belt kit it's probably going to have to wait a little while. I'd like this in my future set up, but for now I've boxed it up and put it in storage until I can justify the outlay. Thanks to everyone who helped me find the problem. Martin

8th Feb 2017, 12:24 am	#9
camtechman Nonode Join Date: Jan 2008 Location: Milton Keynes, Bucks. UK. Posts: 2,552	Re: Pioneer CT-F 850 Cassette Deck Problem Yep, It's a known problem as you can read here: http://www.tapeheads.net/showthread.php?t=21183 __________________ When I die, please don't let my Wife sell my collection for the amount I told her I paid for it!