JVC HR7700EK not playing - UK Vintage Radio Repair and Restoration Discussion Forum

Malcolm G6ANZ · 6th Jun 2014, 12:35 pm

I have this monster VCR that came from work so I know its had little use. The fault is that it won't play. It will load a tape and fast fwd and rewind. Press play and it threads the tape and spins up the drum but the tape does not move. After a few second the tape unthreads and it goes back to stop. It has played and does produce good pictures but then when it started playing these was a loud mechanical 'clunk' as a solenoid pulls in, this 'clunk' is not present in the fault state. My thinking is that a 'tape present' detector is faulty. The tape load mechanism is not as good as it should be and requires some assistance to get the tape to load. I have replaced the load drive belt as this was stretched.
Any ideas?

Malcolm

Nickthedentist · 6th Jun 2014, 12:44 pm

The "tape present" detector is usually the central incandescent lamp plus the two opto sensors at either side of the cassette. The fact that you get some activity suggests this part of the system control is OK.

Is there any take-up reel movement?

My guess would be on an open-circuit circuit protector or dry joint, but I don't know this model. And are the belts OK as a slack loading motor belt could conceivably cause this symptom too. Have you got the manual?

Nick.

BTW this is the same as the Ferguson 3V23, which will perhaps be more familiar to most in the UK.

MALC SCOTT · 6th Jun 2014, 1:44 pm

Loading belt u/s.

steviewonder · 6th Jun 2014, 2:05 pm

Seconded and thirded,slack loading belt!

Malcolm G6ANZ · 6th Jun 2014, 3:45 pm

Thanks. If by the loading belt you mean the belt on the small motor to the right of the load mechanism which drives the chain loading via a worm gear then I've changed it. It was slack but not now. The tape detector lamp is on. When it tries to play there is no movement at all from the take up spool. As far as I can see the other belts are OK although I will give the system another check over.

Malcolm

8 Tracker · 6th Jun 2014, 3:55 pm

From the symptoms you describe, it sounds like the machine is not finishing the loading cycle. Are the two guides that wrap the tape round the head drum reaching the end of their travel? Somewhere there will be a switch to tell the micro that these two guides are in position. On older machines, this was often just two spring contacts. Have a look on the underside and see if you can see it. It may need cleaning.

Mark.

Malcolm G6ANZ · 7th Jun 2014, 9:21 am

I think have got it. 8 tracker was right. as was those who suggested slack belts. the loading arms were stopping just short of actuating the loaded microswitch. by rotating the load motor a small amount by hand the switch clicked in and the machine started playing. With it switched off and the cassette out moving the thread motor over its full range by hand there is a pout at the end of its travel where the movement becomes slightly stiffer. It seems that the slack drive belt started slipping at this point so the thread cycle could not be completed. A new belt on this drive and it seems to be fixed. I'll keep threading and unthreading it to prove to myself that it s fixed as it seems too simple.
The next job is to sort out the eject as the cassette jams somewhere, this may be caused by ancient grease being sticky.
Thanks to all who replied you combined wisdom has saved my thinning hair

Malcolm

Nickthedentist · 7th Jun 2014, 10:07 am

Well done! Another nice machine saved for now.

John123 · 7th Jun 2014, 11:32 pm

IIRC cassettes getting stuck (on eject) was a common problem with the Ferguson 3V23. I remember you had to very gently (and slightly) sand down the little rollers that aid the cassette in and out. Worth a shot!

Malcolm G6ANZ · 8th Jun 2014, 1:27 pm

Cleaned the cassette tray and the rollers. The cassette now loads and ejects OK. Cover on and in use.
Thanks again all

Malcolm

mark pirate · 9th Jun 2014, 8:20 am

I repaired mine using rubber rollers from a scrap printer, works a treat

Mark

6th Jun 2014, 12:35 pm	#1
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,041	JVC HR7700EK not playing I have this monster VCR that came from work so I know its had little use. The fault is that it won't play. It will load a tape and fast fwd and rewind. Press play and it threads the tape and spins up the drum but the tape does not move. After a few second the tape unthreads and it goes back to stop. It has played and does produce good pictures but then when it started playing these was a loud mechanical 'clunk' as a solenoid pulls in, this 'clunk' is not present in the fault state. My thinking is that a 'tape present' detector is faulty. The tape load mechanism is not as good as it should be and requires some assistance to get the tape to load. I have replaced the load drive belt as this was stretched. Any ideas? Malcolm

6th Jun 2014, 12:44 pm	#2
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,841	Re: Jvc hr7700ek not playing The "tape present" detector is usually the central incandescent lamp plus the two opto sensors at either side of the cassette. The fact that you get some activity suggests this part of the system control is OK. Is there any take-up reel movement? My guess would be on an open-circuit circuit protector or dry joint, but I don't know this model. And are the belts OK as a slack loading motor belt could conceivably cause this symptom too. Have you got the manual? Nick. BTW this is the same as the Ferguson 3V23, which will perhaps be more familiar to most in the UK. Last edited by Nickthedentist; 6th Jun 2014 at 1:02 pm.

6th Jun 2014, 1:44 pm	#3
MALC SCOTT Octode Join Date: Aug 2006 Location: Willington, County Durham, UK. Posts: 1,499	Re: JVC HR7700EK not playing Loading belt u/s. __________________ Malc Scott

6th Jun 2014, 2:05 pm	#4
steviewonder Tetrode Join Date: Apr 2012 Location: Manchester, UK Posts: 92	Re: JVC HR7700EK not playing Seconded and thirded,slack loading belt! __________________ Due to recession, the light at the end of the tunnel has been switched off...

6th Jun 2014, 3:45 pm	#5
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,041	Re: JVC HR7700EK not playing Thanks. If by the loading belt you mean the belt on the small motor to the right of the load mechanism which drives the chain loading via a worm gear then I've changed it. It was slack but not now. The tape detector lamp is on. When it tries to play there is no movement at all from the take up spool. As far as I can see the other belts are OK although I will give the system another check over. Malcolm

6th Jun 2014, 3:55 pm	#6
8 Tracker Hexode Join Date: Jul 2009 Location: Mablethorpe, Lincolnshire, UK. Posts: 286	Re: JVC HR7700EK not playing From the symptoms you describe, it sounds like the machine is not finishing the loading cycle. Are the two guides that wrap the tape round the head drum reaching the end of their travel? Somewhere there will be a switch to tell the micro that these two guides are in position. On older machines, this was often just two spring contacts. Have a look on the underside and see if you can see it. It may need cleaning. Mark.

7th Jun 2014, 9:21 am	#7
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,041	Re: JVC HR7700EK not playing I think have got it. 8 tracker was right. as was those who suggested slack belts. the loading arms were stopping just short of actuating the loaded microswitch. by rotating the load motor a small amount by hand the switch clicked in and the machine started playing. With it switched off and the cassette out moving the thread motor over its full range by hand there is a pout at the end of its travel where the movement becomes slightly stiffer. It seems that the slack drive belt started slipping at this point so the thread cycle could not be completed. A new belt on this drive and it seems to be fixed. I'll keep threading and unthreading it to prove to myself that it s fixed as it seems too simple. The next job is to sort out the eject as the cassette jams somewhere, this may be caused by ancient grease being sticky. Thanks to all who replied you combined wisdom has saved my thinning hair Malcolm

7th Jun 2014, 10:07 am	#8
Nickthedentist Dekatron Join Date: Jan 2005 Location: Oxford, UK. Posts: 17,841	Re: JVC HR7700EK not playing Well done! Another nice machine saved for now.

7th Jun 2014, 11:32 pm	#9
John123 Heptode Join Date: Jan 2007 Location: Luton, Bedfordshire, UK. Posts: 891	Re: JVC HR7700EK not playing IIRC cassettes getting stuck (on eject) was a common problem with the Ferguson 3V23. I remember you had to very gently (and slightly) sand down the little rollers that aid the cassette in and out. Worth a shot! __________________ Regards, John

8th Jun 2014, 1:27 pm	#10
Malcolm G6ANZ Octode Join Date: Feb 2006 Location: Bristol, UK. Posts: 1,041	Re: JVC HR7700EK not playing Cleaned the cassette tray and the rollers. The cassette now loads and ejects OK. Cover on and in use. Thanks again all Malcolm

9th Jun 2014, 8:20 am	#11
mark pirate Dekatron Join Date: Mar 2008 Location: Worthing, West Sussex, UK Posts: 5,185	Re: JVC HR7700EK not playing I repaired mine using rubber rollers from a scrap printer, works a treat Mark