Re: LR14 !?!?
"My first cassette recorder was a Christmas present when I was 11. "
In the 1960s my school pal had a proper large reel-to-reel tape recorder with three speeds. We used it to do Goon Show imitations.
My parents bought me a "portable" Grundig tape recorder - valve technology. You had to plug it into the mains - but it was relatively lightweight. Reel to reel but only 1-7/8 speed mono - with small diameter reels.
Recovered it from my sibling's loft storage a few years ago - and surprisingly it still worked. Was disappointed that the tape with it was one of my recordings of music from the radio - rather than my teenage voice.
When cheap transistor tape recorders came on the market they were similar - small reels and only the slowest speed. To cut the cost the erasing head was just a lump of permanent magnet rather than an oscillating signal.