ZX81 denigrated! (was Re: Approaches to projects)

That was a farily standard connector on Philips tape recorders. The middle pin is a locator only -- the real reason for it was to stop the plug going into European mains scoksts (!). One of the outside pins should be martked with an earth symbol, the other is (of course) the signal pin. The original plug was unpolarised, but carried a red dot to indictate the signal pin. That was the convention. A flat locator on inputs, a round one on outputs. My Philips (I forget the model number, I can look it up) uses those for the speaker outputs. The inputs, line-level output (on the same connector as the radio 'diode' input) are DIN sockets. Said machine is Stereo, 4 speed (including 15/16 ips [1]), can copy one mono track to the other while mixing in the microphone input, and so on. The speakers are somewhat Heath-Robinson. There's one in the case, used for mono playback and the left stereo channel. And another in the lid. For Stereo playback you uncoil a lead from a slot inside the lid and plug it into the RH extension speaker socket. Then put the lid on the right side of the machine, about 2m away. Of course you can also connect up a pair of speakers or a stereo amplifer/speaker system... [1] Yes, the quality is lousy. It's useful in the same way that the HP82161 [2] is useful. In case some swine gives me a tape recorded at that speed. [2[] On-topic at last. The 82161 is an HPIL mini-cassette drive used with the hP41, HP71, etc. It works, but it's fairly slow, and the tapes are essentially unobtaium (and they are not the same as any normal audio tape cassette). I use a 9114 disk drive with my HP calculators, that uses 3.5" DD disks whioch are much easier to obtain, faster, and store about 5 times as much. But I keep the 82161 going because I sometimes have to copy tapes for other HPCC members, etc. It's not in Poole and Molloy, at least on that I can find. Can you give me more description, so I can see if I can identify the Philips equivalent. In particular : It's 4 track, does it have a Stereo socket [3]? What's the cabinet made of (most were rexine-covered plywood, a few later ones were plastic) How many speeds, what are they What controls and connectors do you have? [3] Another odd idea of Philips. On some later 4 track machines there was a 3 pin DIN socket, the connections being the lower (track 3) head winding, ground, and +16V (normally obtained by potting down the HT+ line). You could connect a special Philips pre-amplifier there and : a) play back steereo tapes (LH channel throug hte machine, RH channel through the pre-amplidier and the pickup input of your radio set!) b) Monitor track 3 on headphones (the pre-amp could drive the Philips headphones) while recording on track 1 c) Copy track 3 to track 1 (link output of the pre-amp to the input of the recorder) while mixing in another signal (these models had separate recordign level controls for the microphoen and radio/pickup input, thus giving a simple mixer). I will see what I can do.... -tony