Tandberg AT 771 Portable Mono Cassette Recorder

[DMcMahon]

Brought this quite some time ago at a local car boot sale. After some haggling got the asking price down to £6, it came with no mains lead, batteries, tapes or any other accessories and was sold as "maybe working".

Unable to find any technical information, only thing online is a couple of YouTube clips and a couple of old sales.

Would guess 1970's vintage, condition wise pretty good with some minor marks consistent with its age.

Think it looks quite attractive with its coloured operation push buttons, looks well made and feels sturdy.

It is called "Educational Audio Tutor" so presumably was intended for use in the classroom of schools/colleges.

It plays music cassettes very well with good quality sound and plenty of volume. Fast wind in both directions also works very well. Yet to test recording.

David

[DMcMahon]

Three mechanical issues to sort:-

1. Metal side panel was loose and a bit bent, have removed and straightened it out, need to glue it back on.

2. The tone control shaft is bent, so when rotated it is wonky, it must have had a hard knock, need to straighten the shaft.

3. The reset button is missing from the tape counter (the counter does reset to 000 when operated), need to find something suitable and glue it on.

David

[Edward Huggins]

At least the speaker is a decent size. How many radio and cassette portables have we seen with an oversized speaker grille suggetsing a good diameter drive unit behind it!

[Restoration73]

There are similarities with ITT CX-75, which was also of Japanese origin.

[DMcMahon]

Yes 6"/150mm for the Tandberg, probably one of the main reasons for the good sound.

David

[DMcMahon]

Originally Posted by Restoration73

There are similarities with ITT CX-75, which was also of Japanese origin.

Yes somewhat similar, the speaker does not look as good though, I wonder if the ITT schematic (on radiomuseum) is similar to the Tandberg circuitry.

David

[ben]

I wonder if that's a Sanyo mech?

[DMcMahon]

Do not know how to identify a Sanyo mech.

The mech appears different from the ITT mech because the Service manual for the ITT says it only has 1 drive belt, whereas I can see at least 2 belts in the Tandberg.

I am thinking of removing the chassis (which will give a better view of the mech) to repair the broken tape counter reset button, but it looks a bit tricky.

David

[DMcMahon]

Does the orange (may look a bit more yellow in the attached photo) rectangular label between the 2 tape sprockets signify anything ?

My Uher CG 310 has basically the same type label.

David

[Boulevardier]

I've always assumed that those coloured patches were just put there to aid visibility of the amount of tape left on the two spools when looking through the cassette's perspex. Grey/black wouldn't be a good background colour against which to see that.


Mike

[dazzlevision]

I can see some alphanumeric characters on the PCB's copper etch, perhaps if you post that it might help to identify the manufacturer?

The speaker is made by Matsushita (now renamed Panasonic).

[Nickthedentist]

Originally Posted by Boulevardier

I've always assumed that those coloured patches were just put there to aid visibility of the amount of tape left on the two spools when looking through the cassette's perspex. Mike

Yes. Earlier ones had a polished strip of mirror-like metal. Posh hifi decks often had a rectangle of translucent plastic backlit by a small lamp.

Fluorescent orange seemed to be a late 1970s Japanese thing.

[DMcMahon]

The PCB has a JVC number (JVCS73HB) so possibly indicating that the mechanical tape mechanism could be JVC.

The PCB also has VMW-2048 on it.

David

[DMcMahon]

Glued the RHS metal side panel back on and straightened the bent tone control shaft.

Partially removed the tape mech from the front panel (left wiring connected), cleaned the heads and other tape path components, everything really clean looking already actually.

Removed the PCB from the underside of the tape mech, it was secured by 4 small machine screws. 3 of the screws came out easily, the 4th one undid a couple of turns then seized up solid, unable to move it either direction. Had to use heavy long nose pliers to physically unscrew it, it was really tight (no sign on these screws of loctight/threadlock). Attempting to move the screw with screwdriver just chewed up the small Philips head. Need to find a replacement screw and hope can get it to screw back in.

The tape mech has 3 rubber drive belts.

David

[Nickthedentist]

Yes, JVC must have been the OEM then.

JVC certainly made stuff with other companies' branding and specs; there were dozens of versions of their HR-7200 video recorder for example, with names like Ferguson, ITT, Telefunken, etc.

Look at this model, pic borrowed from eBay. There's more than a passing resemblance.

Yours looks very clean inside. Sometimes, educational stuff spent most of its life in a cupboard. Certainly at my GLC/ILEA primary school in the late 1970s/early 1980s, there was a storeroom packed from floor to ceiling with radios, cassette recorders, record players, reel-to-reel recorders etc. most of which never saw the light of day. I bet yours was fished out of a school WEEE skip!

[paulsherwin]

It does look Japanese despite the Tandberg branding. I bet the transistors are Japanese types. It's obviously relatively high quality, and may be OEMd by JVC.

(Crossed with Nick)

[ben]

While in there, you may want to give the rubber spool table outer tyres and the idlers (one at back side, off the capstan; other on the spool table side) a once-over with fine sandpaper to remove the outer surface. Check also that the auto stop senor arm moves freely.

[DMcMahon]

Difficult to see in Post 1 photo 3 but the label on the rear panel says "Made in Japan for Tandberg Educational / Norway".

David

[paulsherwin]

Interesting that it was made for Tandberg Educational. They were mostly concerned with language lab stuff - it's difficult to see how a domestic radio cassette fits into that.

[DMcMahon]

The 2 output transistors are 2SC1568 which are Panasonic.

David