Watkins Copicat MkII ........... shocking state to get into
Best viewed at 1280 x 1024 pixels
1) These days ebay always has a good selection of 'Vintage and Rare' solid state boxes claiming to be 'The Sound of the Shadows' Quite apart from there being thousands (all right, hundreds) of them about, I don't think Hank ever used a Copicat.
That said, in it's time the Copicat was THE thing to have and it was the nearest thing you could get to a 'Talent' switch on your amp. For an expert run down on it's history and workings (or for spares/repairs) visit John Beer's site at
The types that genuinely are hard to come by these days are the valve (tube) versions. As a lad I had a blue panel one in a light blue/cream case. Isn't it marvelous what you can afford when you still live with your parents.
The unit in this case is a valved MkII with a black panel and black and cream case. The logo is Watkins rather than the later WEM and the components are mounted on a tag board. I sent John some pictures and he wasn't impressed.
'Good luck with restoring that one, don't think I would bother to be honest'.
Good advice. I should have taken it.
2) The starting point for this job was to assume that the thing was scrap. There just wasn't enough good stuff left among the rust to salvage. I wanted to document one of these anyway so I decided to strip it down and rebuild it as sympathetically as possible with new components.
3) First job was to take everything off the metalwork. There are two sections, the front panel and a sub chassis which holds the valves and tag board. 
The sub chassis was rubbed down and filled with Plastic Padding Super Steel. I've used this stuff on an aluminium V8 engine block and it's really tough.
After flatting with wet & dry, it was sprayed with red oxide primer and metalic gold cellulose. I tried brush painting with gold Hammerite to match the original, but I couldn't get a decent finish.
Before that, the large hole for the power supply cap was enlarged and redrilled to take a modern replacement. (See below).
4) The original power supply can was a three section 20/20/20uF by Hunts and it was very rusty. It's a waste of time putting another old one back so I fitted a new JJ 40/20/20/20uF. I used it as a 40/20/20 and linked the unused section to ground. The JJ and it's mounting clip are fractionally bigger than the Hunts, hence the rework on the chassis.
5) The front panel was easier. The back has been rubbed back to bare metal and sprayed with red oxide and grey cellulose. The paxolin fuse holder/voltage selector is riveted in so I worked around it.
The front of the panel has been left as found for the moment. I did consider making up a new screen print drawing for it, but the cost would be out of all proportion to the value.
6) The tag board is insulated from the chassis by a strip of flexible material similar to old Fender eyelet boards. Both the board and insulator have been replaced. The insulator is now a sheet of thin paxolin.
7) There's not a lot of room when the board is screwed to the chassis so the wires were attached first.
Resistors are new carbon composition and non electrolytics are from my spares stock.
The old rectifier is going to be replaced with a 1N4007 mounted on standoffs.
8) Mains Wiring Layout
I've been having a think about the mains wiring on this thing and how to make it a bit safer. The system as it stands relies on the connecting lead to the amplifier for a ground connection as there's no dedicated ground wire in the mains lead. That hasn't been too much of a problem in the past and there are still thousands of happy Watkins users alive and kicking. However, entertainment venues, particularly those run by local Councils, have started asking in advance for PAT (Portable Appliance Test) certificates for all electrical equipment taken into the building. That includes the band's gear. No certificate, no gig.
For more details go to http://www.pat-testing.info/
They're not being awkward. Penalties under EU health and safety legislation are severe if employees or the general public are put at risk. Testing isn't expensive. There are companies that will come out and test all the average band's gear for about £50. Ask them to bring some sort of photo ID and proof of competence (City & Guilds Certificate preferably). It's very important to get ALL the gear checked. Having really good ground connections on the back line will guarantee sudden death if the PA system's faulty.
There are three parts to the test.
Correct wiring and physical condition of the mains lead.
The resistance of the earth wire from the plug to the exposed metalwork, usually at 8amps or 25amps AC depending on the test set used.
The leakage current with 500volts DC applied between the live and neutral pins joined together and the earth pin of the mains plug.
PAT testing (or PA Testing if you want to be pedantic) doesn't actually involve taking the unit apart, so you can see that it isn't a substitute for a proper service. The equipment will need re-testing every year (or more often if it gets very heavy use).
The problem with old Copicats is that they don't come under any of the modern test classes. They're really Class 0, an unearthed metal appliance with a two core cable, illegal since 1975.
To make it safe and testable all we really need to do is fit a new 3 core mains cable and earth the exposed metalwork. The motor might need hard wiring to the case if it's insulated by rust or paint (the spindle sticks up through the front panel). It should then fall into the Class 1 category.
That may bring on the old problem of hum caused by an earth loop. I'll come back to that when I get it running.
9) The head selector switch was in a dire state. The only option was to take it completely apart. This is guaranteed to break something.
10) Progress to date.
The head selector switch is back together. I found some replacements for the very small springs on the selector switch at http://stores.ebay.co.uk/Brocotts
Type - Expansion / Tension Springs
Length - 8mm (includes the end loop eyelet)
OD - 3.2mm
Profile - 0.2mm
Material - Passivated & Corrosion Resistant
The supporting metalwork has been cleaned up and coated with cold galvanising spray paint.
This is what's inside the voltage selector - fuse link. Warm up the plastic with a hair dryer before levering it out.
The fuse measures about 6x12mm but it was probably spec'ed as 1/4" x 7/16". Anybody know where you can get some?
It's rated at 1amp and looks like a quick blow (F) type. It should be easy enough to dismantle a new 20mm fuse and fit the filament into the short body.
11) Why doesn't it fit?
I can see why the edge of the sub-chassis has corroded away, this transformer doesn't fit the holes in the front panel properly. It's a factory original so perhaps they were using up the old metalwork. That could also explain why there were only two screws holding it in. This set up seems to be common on black and white versions with "Watkins" logos, the proper four screw arrangement appearing on black and white "WEM" units. (The transformer painting's not finished yet).
12) Head wear.
Three of the heads are original Marriotts and they're beyond help. What look like a fairly solid pieces of metal either side of the head gap are actually thin foil and regrinding (lapping) isn't possible. On the Brainiac principle of "We do it so that you don't have to", this is what happens if you try. New heads all round then.
Just out of interest, these are the measurements taken from some old heads.
Head 1 (Original Marriott from MkII valve unit) 413ohms, 464mH
Head 2 (Original Marriott from MkII valve unit) 420ohms, 455mH
Head 3 (Unknown manufacturer taken from an IC300 solid state unit) 69ohms, 106mH
Head 4 (Unknown manufacturer. Erase head taken from IC300 solid state) 26ohms, 1.66mH
Measurements were done on a Marconi LCR bridge, resistance at dc and inductance at 1kHz.
13) Tension arm.
The tape tensioning arm looks innocent enough from above, but there's a lot hiding underneath it. At first sight the inserts in the wheels look like impregnated phosphor-bronze, but the colour isn't quite right and they could just be brass running on steel shafts.
The magnet was jammed in with a length of hook-up wire sleeving. The poles were at an odd angle so that was probably a DIY job after it fell out.
If you ever get your Copicat stripped down this far you might as well replace the magnet and tension spring while your at it, both are available from http://www.amp-fix.com/ for just a few pounds (along with just about any other Copicat spare you could think of ). Adjust the new magnet so that it's close to the tape but not actually touching it, with the slot between the poles going from top to bottom.
If the magnet's missing just check that you haven't got a later version fitted with an erase head but still using an old style arm.
14) Just to prove that I'm actually doing something to it, here's the front panel on the way back to life.
The motor has been stripped down, treated with Kurust, cleaned and lightly lubricated ( I haven't tried a proper re-oiling job on the sleeves ). It runs extremely quietly at the correct speed, but it gets quite hot. I've got a feeling this is normal although I've never run one on it's own before without the valves chucking out heat. I'll find out what the actual temperature is when I get a minute.
The motor is from Garrard, the record deck people, and features an extended drive shaft and brass flywheel.
The weight of the rotor is taken on a single ball bearing in the bottom housing (at the top in this picture) and the shaft is kept central by top and bottom gimballed sleeve bearings. I don't think these were ever intended to be serviced and should really be described as "sealed for life". It says a lot for Garrard quality that so many of them are still going strong.
The blue sleeves on the transformer hide the joints where the wires have been extended. After forty odd years they were getting a bit dodgy so I've replaced the lot.
15) I thought it was going a bit too well.........
I just realised that the new tag strip from TAD is too big. It collides with the switch assembly and it's got to come out again. ###### it !
More pics as soon as I get an old tag strip. I'm going to need another one for the top of the selector switch assembly as well.
16) Amp-fix to the rescue. Thanks John.
New tagboards in the post from Devon this morning.
Some of the joints are left unsoldered where the footswitch and output cables attach. They can get in the way so they're best left till last.
17) Switch assembly wired in.
18) Input jacks.
I made the mistake (again) of getting the new input jack sockets from the local holiday camp electronics hobby store. As usual there's a problem. The fibre washers supplied are nowhere near thick enough and I've had to find a couple of extra ones. The panel would have to be a foot thick to use these things as supplied.
Not to worry, they fitted in the end. I've used the original white surrounds to keep the front looking more original.
19) Watkins Copicat Schematic.
While I save up for some more spares, this is my attempt to make sense of the head switching arrangement.
20) More soon.