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 21st Jan 2015, 3:19 pm   #201
Guest
Guest
 
Posts: n/a
Default Re: WEM Copicat Custom

Quote:
drumroll please...
With echo!

I remember these from my 70's "in a band" era, being the techy I had to fix it all. The tape loops came in a nice box, much to the joy of our lead guitarist (who used the Copycat). I kept the old boxes and 'refilled' them with any old bit of tape spliced together, same result.
 
Old 21st Jan 2015, 3:36 pm   #202
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: WEM Copicat Custom

Is the contact in the footswitch a make or break type?
__________________
Quote:
Originally Posted by ColinTheAmpMan1 View Post
Quote:
Originally Posted by evilmoisture View Post
@station x no the footswitch is exactly that, a switch. However my friend said it was broken, and he cut the cable, so there are just 2 wires which can be twisted together to switch it "on".
IF you take a close look at the schematic that you posted, you'll see that when the foot-switch is in the closed position, the echo signal is shorted to ground. I believe that this is true of most (if not all) Copicats. So, twisting the wires together will kill the echo, not turn it on. Could that be your problem?

Regards, Colin.
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is online now  
Old 21st Jan 2015, 7:55 pm   #203
Pitchfork
Tetrode
 
Join Date: Jan 2015
Location: Tadley, Hampshire, UK.
Posts: 77
Default Re: WEM Copicat Custom

Correct, shorting the wires switches off the effect. I repair & refurbish Copicats of all marks, whoever told you to join the two was grossly incorrect.
Pitchfork is offline  
Old 21st Jan 2015, 8:48 pm   #204
evilmoisture
Retired Dormant Member
 
Join Date: Dec 2014
Location: Ile-de-france, Paris, France.
Posts: 84
Default Re: WEM Copicat Custom

I third that, when the footswitch is closed (wires twisted together) it sends the play head signals to ground.
Interesting point made on page 10 (Omegaman I think?) that it was possibly modified to use as an overdrive; this obviously being a good example of how confusing these kinds of modifications can make future repairs. This R11 (actually didn't even know its number) sticking up (and a jumper wire touching it) was the first thing I noticed, and all the time the idea that it was just incorrect wiring was bugging me...however I would've been too scared to blow up more caps etc to have tried rewiring it, plus variations in schematics adding to my uncertainty.
Then again the quirky nature of these copicats is why they became so popular, it was almost the engineering flaws which gave them their unique sound. No disrespect to Charlie Watkins but in an interview I watched recently he does come across as a charming used-car salesman almost Benny Hill-like character (!)
Making the drawing was a great suggestion, otherwise I fear it might have dragged on longer... then again my friend got some new caps in the process which should extend its lifespan. Seriously, thanks for solving this, and echoed drumrolls for being so patient, observant, and helpful!
evilmoisture is offline  
Old 21st Jan 2015, 10:09 pm   #205
AC/HL
Dekatron
 
AC/HL's Avatar
 
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,637
Default Re: WEM Copicat Custom

If whoever did the mods had just scribbled some information on a scrap of paper and put it inside, it could have saved a lot of head scratching!
AC/HL is offline  
Old 21st Jan 2015, 11:44 pm   #206
PJL
Dekatron
 
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
Default Re: WEM Copicat Custom

Glad to hear it works.

Thanks for giving me something useful to do whilst sitting in this hotel room in Ohio USA, hence the odd posting time...
PJL is offline  
Old 21st Jan 2015, 11:47 pm   #207
evilmoisture
Retired Dormant Member
 
Join Date: Dec 2014
Location: Ile-de-france, Paris, France.
Posts: 84
Default Re: WEM Copicat Custom

Quote:
Originally Posted by AC/HL View Post
If whoever did the mods had just scribbled some information on a scrap of paper and put it inside, it could have saved a lot of head scratching!
Absolutely. Inversely I'm quite interested in what this overdrive conversion consisted of, not to build it, just to understand...I assume it's something like feeding the input amps through the head amps so that they saturate/distort, and then straight to the output. The same as 2 gain stages in a valve guitar amp in fact.
If I were to do any mods, not to this one but perhaps a transistor one, it would be to add more heads, and a variable speed DC motor, or movable heads...
evilmoisture is offline  
Old 22nd Jan 2015, 12:06 am   #208
ITAM805
Nonode
 
ITAM805's Avatar
 
Join Date: Jul 2010
Location: Folkestone, Kent, UK.
Posts: 2,172
Default Re: WEM Copicat Custom

Back in the 70's I used to use a Mk2 copicat not only as an echo, but as an overdrive into a 100W Marshall - ever so good it sounded too

Also used it to lively up our band home recordings, not only for overdrive but the impedance of the 'cat' was a better match for our guitars into the Akai and Sony recorders we were using.

Well done to PLJ and Howard for the diagnosis!
ITAM805 is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 12:33 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.