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ID an electronic component ?? - Printable Version

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ID an electronic component ?? - TASP - 03-19-2016 03:52 AM

Put on your thinking caps.

I think it was back in the 1980s, I saw a new product announcement in High Fidelity, or Stereo Review, or Audio, or some other hi-fi related publication, of a little device you could put on your turntable (for the younger readers here, probably best to give up on this thread now, sorry) that would monitor the operating time on your stylus. (I'm not kidding, younger readers still on this thread need to bail now, it will get worse).

As we old farts recall, a worn stylus in the groove of your vinyl LP would impair the fidelity and damage the record too. Any how, this particular timer was really simple; not counting electrons, it had one moving part. As I recall, it was a thin glass or quartz tube, maybe an inch long, with a tiny bead of mercury (or something in it), and it was wired to the turntable motor. In operation electrons would very slowly evaporate (or push?) the bead down the tube and it took hundreds of hours, and that interval was comparable to the lifetime of a stylus. When the bead hit the end of the tube, you replaced the stylus, and flipped the tube over, since it took the same amount of time to put the bead back, it was just easier to do it that way to reset the 'timer'.

Anyhow, not much need for stylus hour meters these days, but that device was super low power draw, did something useful (kept track of operating times in the hundreds of hour range) and I'll be damned if I can remember what the tube was called. I've tried googling every permutation of all the keywords I've used in this post and come up with nothing.

Annoyingly, I have kept all my back issues of all those hi-fi magazines, but without a comprehensive index, I'll never find the issue in the remainder of my lifetime.

I think it's odd, something that useful never found wider use in other applications or at least some fleeting mention in wiki, or on the net somewhere I could find, but to date, nothing.

Anyone here ever learn of such a device? What it's called? Why did it never find wider use?

Appreciate anything anyone recalls.

RE: ID an electronic component ?? - Steve Simpkin - 03-19-2016 04:54 AM

I remember those!

Here is an example of a homemade one.

Here is an example of one made by Pickering.
The Pickering stylus timer PST-1


RE: ID an electronic component ?? - Garth Wilson - 03-19-2016 05:12 AM

I remember seeing them sold for other (industrial, not turntable) purposes at an electronics-industry trade show in the mid- to late-1980's. I might still have the literature I picked up on it in my files, but at this point I don't know where I'd even start looking.

For keeping a record of stylus wear, I just put a tally mark on a piece of paper for every LP side played. With the average being 15-20 minutes a side, you could divide the number by three or four to get an approximate number of hours.

Yeah, young people these days don't know what a turn table is, or a tape recorder, or the Fotomat store, or why we say "dial a number" or "hang up" or any of so many other things. Although I wasn't so established back then, in many ways life was better, and I'd be glad to go back to it.

RE: ID an electronic component ?? - TASP - 03-19-2016 05:17 AM

The home made one isn't ringing any bells, but the Pickering model is what I am recalling.

Looks like I scrambled the details enough in regards to how it works, but that is it.

I knew someone here would recall the item. The PM article is actually quite useful.

Thanx so much.

RE: ID an electronic component ?? - TASP - 03-19-2016 05:37 AM

"Coulometer" is the term I found for the device and there is a nice write up in Wiki on it.

I suppose using mercury is the problem why these devices aren't used to time things these days. Still, its a real clever gizmo. Wiki lists some other variants on the idea, some surprisingly old too.


RE: ID an electronic component ?? - Steve Simpkin - 03-19-2016 05:57 AM

Very cool.
It always amazes me what people were able to invent using the technology that was available at the time. Whether it was the Apollo spacecraft or the HP9100A, they were stunning achievements.

RE: ID an electronic component ?? - TASP - 03-19-2016 06:16 AM


I may joke about Babbage's difference engine from time to time (like the forum software is running on it right now), but it was an amazing feat to design it at the time, let alone attempting to build it.

The anti-Kythera mechanism is another. Oh for an intact one to turn up somewhere . . .