Those of you with even the most rudimentary knowledge of tape recorder operation will know that a capstan and pinch roller arrangement is used to pull the tape across the heads at a constant speed. Back in the 1960s some inexpensive, very basic miniature reel-to-reel recorders – effectively little more than toys – appeared on the market which dispensed with these components and moved the tape by the force of the take-up spool alone. With this method the linear speed of the tape gradually increased as the spool filled up and its diameter got progressively larger. As a result, tapes recorded on these machines and played back on a conventional one with a capstan exhibit a gradual, continuous slowing down from beginning to end, which makes them a nightmare to digitise!
Around the same time Philips introduced the Compact Cassette as a small, easy-to-use speech recording medium. It was quickly found to be somewhat over-specced for its intended purpose; pre-recorded ‘musicassettes’ soon appeared and a couple of years later the format went stereo – and it took off from there. So the Philips engineers went back to the drawing board to design an even smaller, even easier-to-use speech recording medium and in doing so took a look at those crude, capstanless machines. The result was the minicassette, a twin spool double sided format just like its larger brother, but stripped down to the absolute basics and having no fixed speed. Presumably there’s a specified rotational speed of the take-up spindle, but compatibility between machines seems to be poor.
Not long afterwards Olympus in Japan introduced the superior, capstan-driven microcassette. A successful rival for speech recording but its pinnacle of development as a stereo music medium, using Type IV (metal) tape, in the 1980s fell flat on its face. It was, perhaps, pushing analog tape technology just that little bit too far. Nevertheless, for miniature speech recorders which could be held in one hand, the two formats happily co-existed for the remainder of the 20th century, the Philips system scoring with its robust simplicity. My first encounter with a minicassette recorder was in the early 1980s when my mother brought one home from work; whether they had a peak in popularity around this time, and whether this was in turn due to some rather blatant product placement in For Your Eyes Only, I really couldn’t say.
So here is more ‘stuff’ from my late uncle. The two machines are an LFH 0185/00 and an LFH 0585/10. Both are made in Austria. There’s also a conference microphone with its carrying case and a stack of cassettes, most of which are unused. The 585 was manufactured in 1981; all I can determine about the 185 is that it’s clearly an older model. They both run from a 9 volt PP3 battery; later (1980s onwards) machines changed their power requirements to two ‘AA’ cells, clearly taking advantage of economical ‘Walkman’ technology.
The transport control is operated by the thumb when held in the right hand – up to play, down to stop, and further down (non-latching) for rewind. The 585 also offers high-speed playback (‘monkey chatter’) when this control is moved further up from the ‘Play’ position (again, non-latching), and a facility to lock it in the ‘Stop’ position. Recording is accomplished by a button on the top surface of the 185 and a slide switch on the left-hand side of the 585 – in both cases operated by the forefinger – which latches down and enables the unit to be stopped and started in ‘Record’ mode. It’s released by operating the rewind function (or alternatively the high-speed play function on the 585). As well as performing the necessary switching, this control also physically moves the ‘erase head’ (actually a permanent magnet) onto the tape. Apart from a playback volume control, that’s all there is to them!
Inside, the electronics are surprisingly complex; they have bias oscillators in order to get the best possible recording quality onto the tiny tape, but presumably it was decided from the start that an energised erase head, with the resultant additional battery drain, was not justified in the circumstances. However, they don’t seem to have an automatic recording level or if they do then it has a very limited range – the louder you speak or the closer you hold the unit to your mouth, the louder it plays back. The 185 has discrete transistors throughout whilst the 585 utilises an integrated circuit loudspeaker amplifier.
Looking specifically at the 185, it has a nasty cheap plastic case which clips together. Of course, these clips go brittle with age and have a tendency to break off – one of them has, and now the bottom left corner of the case is loose. Inside, though, the chassis and circuit board look to be of very high quality. There are two sockets, one for the conference microphone (the built-in mics on these machines are designed for close-range use) and another for a DC power input. At present this machine doesn’t work because the drive belt has disintegrated, which seems to be a Philips trait. It’s smaller and thinner than a ‘Walkman’ belt (of which I have plenty) and sourcing a replacement is low priority.
Meanwhile the 585 is a completely different animal. Although a more advanced model with the additional high speed play function, a look inside reveals much reduced manufacturing costs, notably the chassis for the tape transport now being of plastic construction. There are no sockets but the spaces where other variants of this model have them can be seen.
Not only did this crude system happily co-exist with the microcassette, it has indeed outlasted it, and minicassette recorders are still manufactured today (q.v.). Apparently no other format – capstan-driven tape and solid state digital alike – does ‘cue and review’ quite as efficiently. A truly remarkable survivor!
The Technojunk Files 