Ultra 6212 Reel to Reel 4 Track Recorder

[SteveCG]

I have an Ultra 6214 tape-recorder, bought at a jumble sale some time ago, and never tried. It is a 1/2 track, 3 3/4 ips only, 5 3/4 inch spool machine, which has a magic eye recording level indicator. I presume it is a valved job. Given the closeness in the model numbers to the 6212, I was wondering whether it is related internally? What are these machines like for the 'that capacitor' syndrome? Does it use drive belts?

[brenellic2000]

Never had any problems (so far!).... I'll consult my crystal ball! My little Lustraphone seems indestructible - but then so are all Lustraphones!

Just had a thunk! Is the microphone socket on these Thorn decks 5- or 8-pin? I can't remember now... where did the Synch-amp plug into?!

Thorn made 3 decks: DB21/41 3-3/4ips 5-3/4", DB42, 2-speed and this superb 3-speed DC43 7". Electronically they differed little but there are some mechanical differences. Their last decks, which replaced these, are quite different.

Model numbers don't follow any logic, apart from the first which identifies it as Ultra, HMV etc...

Barry

[Heatercathodeshort]

The more you post the more junk I have to unearth from my 'museum'..
Pictures here of the incredibly stylish Ultra 6214 two track single speed model. It has the same mic input socket as the four track machine but the microphone does not have the remote switch. Din plug is four pin and the socket has an auto switch for the remote.
Build quality is about as good as it gets at any price with positive piano keys and nice controls. Crystal microphone inserts usually last for ever. British at it's best. Regards, John.

[ricard]

Originally Posted by dazzlevision

Sounds like your Ferguson is the stereo model, with all-transistor electronics?

Definitely stereo, and I think all-transistorized, although I don't have access to the machine right now so I can't verify it.

BTW, someone above mentioned crystal microphones. From my experience it's a hit-and-miss if they still work. I would say the chance of one still working is about 50% in general. Especially if they have been stored under any form of damp conditions they tend to deteriorate.

[dazzlevision]

Originally Posted by Nickthedentist

Do crystal microphones have the same habit of self-destructing that crystal cartridges do?

Hello,

Concerning these specific Thorn crystal microphones, I have acquired several over the years (including the one that came with my Ferguson 3230 tape recorder bought new in 1967). I have found that only one was completely u/s (no output), whereas the others all had a lower output than they would have when first manufactured. This means the record level control has to be turned right up to get correct deflection on the rec level meter and you would have to speak fairly close to the mike. I haven't opened one up, to see who actually made the crystal mic insert (probably Acos/Cosmocord in the UK).

Regards,

Dazzlevision

[dazzlevision]

Originally Posted by SteveCG

What are these machines like for the 'that capacitor' syndrome?

Hello,

Your machine is indeed a valve one (ECC83, ECL86 and EM87). I have repaired several and in all cases, the coupling capacitor to the control grid of the audio output pentode (ECL86 in all of Thorn tape recorders made in the mid to late 1960s, but not the very first ones that used the BSR TD2 deck) is a Polyester type (resin dipped) and should be OK.

Regards,

Dazzlevision

[SteveCG]

Thank you Dazzlevision for the info. I shall have to give it a go, powering it up on a variac first.

BTW are there any mechanical, old-age, issues for this model? I suppose dried-up grease is a potential one.

[dazzlevision]

Originally Posted by SteveCG

BTW are there any mechanical, old-age, issues for this model? I suppose dried-up grease is a potential one.

Hello,

I have mentioned various mechanical issues earlier in this thread. I advise you to get the Thorn service manual for their DB21 & DB42 tape deck mechanisms (1 speed, 2 track / 2 speed, 4 track) or DC43 (3 speed, 4 track) tape deck and the separate manual for the tape recorder itself (there are several firms offering digital or photocopies of service manuals or you could post a "wanted" ad in this forum).

The deck manual will show what needs cleaning/lubricating and all the usual mechanical adjustments. After 40+ years, the original lubrication will have deteriorated.

Regards,

Dazzlevision

[nbm7101]

OK, after waiting weeks to get a microphone, I finally was able to test my machine with a Grundig GDM 314. After a few tests, I started hearing zaps and pops inside the machine. After taking the bottom cover off, I can see that they are coming from the main circuit board. They alternate from a few different places, pop........pop...pop......pop. Is this from moisture? This just started after plugging in the microphone and recording a few short clips.

[dazzlevision]

Originally Posted by nbm7101

After a few tests, I started hearing zaps and pops inside the machine.

Hello,

I have come across sparking from the circuit board to the grey metal screen covering the copper/solder side of the printed circuit board (PCB), particularly at the terminals of the HT smoothing multi-section capacitor. If you take off the screen cover, you may see some marks on the inside face of it, where the sparking has occurred. Either the screen plate has been distorted or maybe a wire/tag on the solder side of the printed circuit board (PCB) is a bit too long and will need cutting back.

Alternatively, there might be a dry joint on the PCB. If any are suspect, remake with a good hot iron and fresh solder.

Regards,

Dazzlevision

[Tractorfan]

Hi,
In response to Nick's question in post 20.
That's a good question. I've never seen a crystal mic go green & gooey. I wonder if it's because the element is sealed behind the diaphragm. I think that the odd one or two I've got kicking round here still work, although I must admit I haven't tried them for a while.
Cheers, Pete

[AlanC]

Just seen this thread... the Marconiphone version was the 'standard issue' tape recorder in Sheffield schools in the late sixties replacing the Philips EL3548's. They were impressive. They were replaced in the mid 70's by Tandbergs that were even more impressive.

As a kid at school, we didn't always have a teacher who could play the piano for assembly so somebody recorded some hymns and I was 'volunteered' to sit at the back of the hall and start and stop the tape recorder at the appropriate places. This was using the Marconiphone. And later on, I used to bring in tapes recorded at home of the Sunday evening top 40 show on Radio 2 and we'd play them at lunch times in the form room again on a Marconiphone- happy days. I seem to remember that the rotary pots were exceptionally free to turn... I'm scratching my head trying to think if they were transistor or valve- I don't remember that they had to warm up? someone please put me out of my misery!
cheers
Alan

[brenellic2000]

Almost certainly valves - the stereo version of 7" 4210 and the new 1970-73 line-up were all transistor, as far as I know.

Their last design from 1970 looked more 'continental' (I think the mechanical designer for these was ex-Philips) and were more plasticy than the 1960s all British Thorn tape-recorders. Thorn did exceptionally well in export markets but open reel came to an end in 1973. Their British built cassette transports were highly regarded especially in schools' recorders.

Barry

[dazzlevision]

Originally Posted by AlanC

I'm scratching my head trying to think if they were transistor or valve- I don't remember that they had to warm up? someone please put me out of my misery!

Hello,

The 7" spools, 3 speed, 4 track mono machines were three valves plus one transistor, but the stereo version was all transistor.

Regards,

Dazzlevision

[nbm7101]

Thanks dazzlevision, post 30, I did notice the black marks around certain solder points. You were dead on, I just went back to these areas and filed down the wire, problem solved!

Now, for the next problem. I am replacing the counter belt. I can see the first wheel the belt fits around, right beside the counter. Now I assume it fits around the left side spindle rotar, but where exactly? Around the base of it? Underneath it? I can't seem to find a manual for this machine

[dazzlevision]

Now, for the next problem. I am replacing the counter belt. I can see the first wheel the belt fits around, right beside the counter. Now I assume it fits around the left side spindle rotar, but where exactly? Around the base of it? Underneath it? I can't seem to find a manual for this machine[/QUOTE]

Hello,

Glad you sorted out the arcing problem.

The other end of the counter belt fits around the step of the supply (left hand side) turntable (i.e. not underneath it). The belt will then be parallel to the deck.

Unless the record/play head is very worn, you should be pleased with the results!

Regards,

Dazzlevision

[nbm7101]

Thanks again goes to dazzlevision, the counter is now counting! Now for a more serious problem.

The volume of this machine is not at full capacity. When I first used it, the sound was fine, but after continued use it has gotten almost inaudible. This morning when I was fixing the arc problem, the sound was back to normal, nice and loud. But after it was all back together, the problem returned.

What is the problem? The volume knob is properly aligned onto the actual adjustment mechanism, and I have it turned to 10. Is it a question of tape to head contact?

[dazzlevision]

Originally Posted by nbm7101

What is the problem? The volume knob is properly aligned onto the actual adjustment mechanism, and I have it turned to 10. Is it a question of tape to head contact?

Hello,

In case there are more shorts due to the PCB's screening plate touching a soldered joint/wire on the PCB, try running the machine without it. Leaving the screen off will increase the background "hum" (50Hz mains pickup in the amplifier) level on playback. If that makes no difference, the screen is unlikely to blame and can be replaced.

Are you sure the tape is making contact with the record/play head? is the tape the correct way round (if it's back to front, you'll hear very little, as the magnetic coating is not touching the tape head)?

Is the felt pressure pad that presses the tape against the rec/play head present?

Is one of the two track selector buttons depressed?

Is there definately a good recording on the tape you are using?

Set the machine to play, with the (latching) pause key depressed. Turn the volume control to max and the tone control fully anticlockwise (without turning the machine off). If you put your head close to the speaker, you should hear some hiss and some hum. This should indicate whether the playback amplifier is working correctly. Depressing the two track selector buttons shopuld cause some pops and clicks and maybe some hum.

Now try something something similar. With the record and then play keys both depressed and then pause, turn up the two record level controls to max as well as volume (tone anticlockwise as before). Set the tape speed to 1 and 7/8 inches per second. You should definately hear a significant hiss from the speaker (and maybe some hum). The far right record level control has the most effect on the hiss and turning it to minimum should reduce the hiss to a very low level. If you get hiss, then the record amp is probably OK as well.

Try these suggestions and report back.

Regards,

Dazzlevision

[nbm7101]

Dazzlevision, as soon as you mentioned PCB's screening plate I knew that was it. Because as I said before, the volume was working great this morning while I filed the soldered wire down. Volume back to normal!

But what does this mean, it's alright to leave the screening plate off?

[dazzlevision]

Hello,

No, you shouldn't leave the screening plate off; it is there for a reason - to stop the electronics picking up 50Hz mains "hum" (for one thing).

Are you sure the screen plate is truly flat? If it is bowed/distorted, then it might come into contact with several points on the PCB. Ensure the screen plate is truly flat and then look for other wires that project excessively from the PCB copper side and cut them back where necessary.

Regards,

Dazlevision