UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Specific Vintage Equipment > Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players

Notices

Vintage Tape (Audio), Cassette, Wire and Magnetic Disc Recorders and Players Open-reel tape recorders, cassette recorders, 8-track players etc.

Closed Thread
 
Thread Tools
Old 12th Apr 2021, 2:11 pm   #61
Edward Huggins
Dekatron
 
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
Default Re: Reps JC20 Reel to Reel

I'm not quite sure where this long and detailed Thread is going?
As far back as Post#42, the OP has clearly stated that he does not wish to use his equpment for music reproduction - they are just for Show only. And here we all are suggesting circuit tweaks...
__________________
Edward.
Edward Huggins is offline  
Old 12th Apr 2021, 4:36 pm   #62
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

I have taken it in today for a full check over and to fit all new capacitors. I'll post back when it's all done.

Thanks all for your help. Les
Starlight 1 is offline  
Old 18th Apr 2021, 8:36 pm   #63
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

I like to say thanks to the man for doing this work for me I do a full post later as I still have lots of work to do .
Les
Attached Thumbnails
Click image for larger version

Name:	IMG_5002.JPG
Views:	57
Size:	181.3 KB
ID:	232079  
Starlight 1 is offline  
Old 19th Apr 2021, 7:05 pm   #64
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

After the electrics were done I now realise I have mechanical problems.
The 2 white and 2 black drive wheels are much smaller than the originals.
I played a tape which sounds like Mickey Mouse and the nearest settings were
3 3/4. I recorded it onto the computer, made adjustments until the speech
became clear and it's running 0.562 out. My plan now is to take the 2 aluminium
take-up pulleys which the rubbers run on, measure all the sizes, lathe new pulleys and add the 0.562 which should bring everything back into spec.
Long way going about it but don't think these rubbers will be obtainable anymore. Just to add the man who did the electrics said the amplifier and the volume is outstanding quality and he was quite happy playing his radio through it.
Starlight 1 is offline  
Old 20th Apr 2021, 8:00 am   #65
llama
Octode
 
llama's Avatar
 
Join Date: Jun 2006
Location: St Osyth, Nr Clacton, Essex, UK.
Posts: 1,482
Default Re: Reps JC20 Reel to Reel

Before going to all that bother, (which sounds counter-productive to me - apologies) can you try a selection of other tapes? I'd send you a studio-quality 7.5ips tape foc but I can't get to the post at the mo.
Graham
__________________
Half my stuff is junk - trouble is, I don't know which half!
llama is offline  
Old 20th Apr 2021, 8:06 am   #66
DMcMahon
Dekatron
 
DMcMahon's Avatar
 
Join Date: Apr 2019
Location: Worthing, West Sussex, UK.
Posts: 6,587
Default Re: Reps JC20 Reel to Reel

Quote:
Originally Posted by Starlight 1 View Post
The 2 white and 2 black drive wheels are much smaller than the originals.
How do you know this ?

David
DMcMahon is offline  
Old 20th Apr 2021, 5:45 pm   #67
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

Quote:
Originally Posted by llama View Post
Before going to all that bother, (which sounds counter-productive to me - apologies) can you try a selection of other tapes? I'd send you a studio-quality 7.5ips tape foc but I can't get to the post at the mo.
Graham
That very nice of you my play back rate is set to 1.00000
and work out RPM on the same tape is 65 so if you add the RPM that will help a lot
Thanks Les
Starlight 1 is offline  
Old 20th Apr 2021, 5:58 pm   #68
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

Quote:
Originally Posted by DMcMahon View Post
Quote:
Originally Posted by Starlight 1 View Post
The 2 white and 2 black drive wheels are much smaller than the originals.
How do you know this ?

David
at 3 3/4 it play ok forwards and backwards------ on fast only work one way--- If I set it to15 fast forwards and back ok so its pushing the rubbers out more adding weight to the take up spools.
Starlight 1 is offline  
Old 21st Apr 2021, 8:38 pm   #69
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

I tried an experiment today. I glued a piece of rubber band to the pulley refitted it to the left side as there was no drive in reverse. This greatly improved the drive and I had to take all the weight off to get it to move as it was really too big. The join in the elastic band makes the tape jump on rotation and it lost all drive on fast forward. Repeating my earlier experiment it was running at 65rpm now it is running at 74rpm to sound the same. I have removed the elastic band but my theory on rubber shrinking or wearing down seems to be correct.
Attached Thumbnails
Click image for larger version

Name:	IMG_5014.jpg
Views:	43
Size:	79.9 KB
ID:	232335  
Starlight 1 is offline  
Old 25th Apr 2021, 8:01 pm   #70
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

I have got there in the end after taking 3 days off, the problem was the counter pully belt mods can close this post as it all done .
Starlight 1 is offline  
Old 25th Apr 2021, 8:33 pm   #71
Starlight 1
Triode
 
Starlight 1's Avatar
 
Join Date: Apr 2021
Location: Norwich, Norfolk, UK.
Posts: 42
Default Re: Reps JC20 Reel to Reel

IF the tape that come with it was last used in 1973
Starlight 1 is offline  
Old 26th Apr 2021, 1:58 pm   #72
Analogue man
Hexode
 
Join Date: Dec 2020
Location: Raunds, Northamptonshire, UK.
Posts: 339
Default Re: Reps JC20 Reel to Reel

Quote:
Originally Posted by Starlight 1 View Post
After the electrics were done I now realise I have mechanical problems.
The 2 white and 2 black drive wheels are much smaller than the originals.
I played a tape which sounds like Mickey Mouse and the nearest settings were
3 3/4. I recorded it onto the computer, made adjustments until the speech
became clear and it's running 0.562 out. My plan now is to take the 2 aluminium
take-up pulleys which the rubbers run on, measure all the sizes, lathe new pulleys and add the 0.562 which should bring everything back into spec.
Long way going about it but don't think these rubbers will be obtainable anymore. Just to add the man who did the electrics said the amplifier and the volume is outstanding quality and he was quite happy playing his radio through it.
The size of the rubber wheels should make no difference to the capstan speed but the white one will affect the take up spool speed but that alone should not make the tape run slow. Are you sure that you are not running 60hz motors on 50hz mains?
Analogue man is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 11:43 am.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.