Groups > alt.folklore.computers > #155255

Re: 1957 LED

Newsgroups	alt.folklore.computers
Date	2015-12-16 07:32 -0800
References	(2 earlier) <396e97cc-39db-46fe-8404-b8c60ec255df@googlegroups.com> <e2d26d9c-7353-4cbb-9c1b-ef85199a2621@googlegroups.com> <sLOdnVJVds5_1_LLnZ2dnUU7-VWdnZ2d@giganews.com> <XnsA5717968B3B92falkarcabca@213.239.209.88> <alpine.LNX.2.02.1512151503510.5698@darkstar.example.org>
Message-ID	<04e31e21-cbc6-4c99-9cc0-e6bb37df69e9@googlegroups.com> (permalink)
Subject	Re: 1957 LED
From	hancock4@bbs.cpcn.com

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On Tuesday, December 15, 2015 at 3:02:18 PM UTC-5, Michael Black wrote:
> Since the photocell dropped resistance with light, I initally couldn't 
> figure out how that would work.  When the light wasn't interrupted, the 
> photo cell would let the voltage from the battery to the bell (I was 
> thinking in terms of "burglar alarm"), but it was when the light was 
> interrupted that you needed the bell.

I don't know the specific technology, but in the 1950s-1960s there
were two types of camera meters.  (Originally the meter was a 
separate device, then later miniaturized to fit into the camera).

Anyway, the earliest meters just measured the light and used it
to drive the meter scale.  I think it was plain photo cell.

Later, better meters required a battery and used a different
photo cell (Cs?).  That measured the difference and was 
supposedly more accurate.

My old Nikon required a tiny battery for the meter; everything
else was manual.  The meter battery lasted forever.  My 
digital Nikon has a battery the size of the Empire State
Building and needs regular charging.  A replacement is $50.

(I suspect when that battery no longer holds a charge, a
replacement won't be available, and I'll have to buy a
whole new camera.  Admittedly, I do like digital better
than film, but the rapid obsolescence is a turnoff.)

Thread

1957 LED hancock4@bbs.cpcn.com - 2015-12-10 11:03 -0800
  Re: 1957 LED Al Kossow <aek@bitsavers.org> - 2015-12-10 11:06 -0800
    Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-10 14:44 -0500
      Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-11 07:41 -0800
        Re: 1957 LED Ahem A Rivet's Shot <steveo@eircom.net> - 2015-12-11 16:37 +0000
        Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-11 14:42 -0500
    Re: 1957 LED philo <philo@privacy.net> - 2015-12-10 13:56 -0600
      Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-10 22:59 -0500
        Re: 1957 LED "Osmium" <r124c4u102@comcast.net> - 2015-12-11 08:20 -0600
          Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-11 14:33 -0500
      Re: 1957 LED Quadibloc <jsavard@ecn.ab.ca> - 2015-12-13 07:58 -0800
        Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-13 13:00 -0500
      Re: 1957 LED Lon <lon.stowell@comcast.net> - 2015-12-13 12:48 -0700
        Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-14 09:07 +0000
          Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-14 11:47 -0500
          Re: 1957 LED rpw3@rpw3.org (Rob Warnock) - 2015-12-16 14:55 +0000
            Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-16 16:32 +0000
              Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-16 14:17 -0500
              Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-16 18:15 -0600
                Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-17 07:58 +0000
                Re: 1957 LED Andrew Swallow <am.swallow@btinternet.com> - 2015-12-17 13:21 +0000
        Re: 1957 LED Ingo Paschke <ipaschke@lpclabs.de> - 2015-12-14 11:11 +0100
    Re: 1957 LED Stephen Wolstenholme <steve@easynn.com> - 2015-12-11 10:58 +0000
      Re: 1957 LED Lon <lon.stowell@comcast.net> - 2015-12-13 12:50 -0700
        Re: 1957 LED Stephen Wolstenholme <steve@easynn.com> - 2015-12-14 12:57 +0000
          Re: 1957 LED "gareth" <no.spam@thank.you.invalid> - 2015-12-14 14:07 +0000
            Re: 1957 LED Stephen Wolstenholme <steve@easynn.com> - 2015-12-14 14:33 +0000
    Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-11 07:31 -0800
      Re: 1957 LED Quadibloc <jsavard@ecn.ab.ca> - 2015-12-13 07:42 -0800
        Re: 1957 LED Ahem A Rivet's Shot <steveo@eircom.net> - 2015-12-14 09:39 +0000
        Re: 1957 LED Jon Elson <jmelson@wustl.edu> - 2015-12-14 17:07 -0600
          Re: 1957 LED Alfred Falk <falk@arc.ab.ca> - 2015-12-15 18:53 +0000
            Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-15 15:05 -0500
              Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-16 07:32 -0800
                Re: 1957 LED Alfred Falk <falk@arc.ab.ca> - 2015-12-16 17:23 +0000
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-16 14:23 -0500
                Re: 1957 LED Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2015-12-16 20:13 +0000
                Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-16 13:15 -0800
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-17 14:53 -0500
                Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-17 14:17 -0600
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-18 19:43 -0500
                Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-20 20:02 -0600
                Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-21 10:31 -0800
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-21 14:53 -0500
                Re: 1957 LED mausg@mail.com - 2015-12-21 20:27 +0000
                Re: 1957 LED Uncle Steve <stevet810@gmail.com> - 2015-12-17 18:48 -0500
          Re: 1957 LED davidmylastname@acm.org (David Griffith) - 2015-12-16 02:43 +0000
          Re: 1957 LED Mike Spencer <mds@bogus.nodomain.nowhere> - 2015-12-16 17:44 -0400
  Re: 1957 LED scott@slp53.sl.home (Scott Lurndal) - 2015-12-10 19:13 +0000
    Re: 1957 LED "gareth" <no.spam@thank.you.invalid> - 2015-12-10 20:17 +0000
      Re: 1957 LED Lawrence Statton <lawrence@sengiuo.mx> - 2015-12-10 17:10 -0600
      Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-10 23:00 -0500
        Re: 1957 LED isw <isw@witzend.com> - 2015-12-10 21:21 -0800
          Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-11 08:01 +0000
            Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-11 14:30 -0500
            Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-11 15:36 -0600
              Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-12 07:55 +0000
                Re: 1957 LED mausg@mail.com - 2015-12-12 11:20 +0000
                Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-12 15:39 +0000
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-12 10:50 -0500
                Re: 1957 LED Stan Barr <plan.b@bluesomatic.org> - 2015-12-13 08:00 +0000
                Re: 1957 LED "gareth" <no.spam@thank.you.invalid> - 2015-12-13 11:10 +0000
              Re: 1957 LED Lon <lon.stowell@comcast.net> - 2015-12-13 12:51 -0700
        Re: 1957 LED "gareth" <no.spam@thank.you.invalid> - 2015-12-11 10:59 +0000
          Re: 1957 LED Ahem A Rivet's Shot <steveo@eircom.net> - 2015-12-11 15:46 +0000
            Re: 1957 LED "gareth" <no.spam@thank.you.invalid> - 2015-12-11 17:37 +0000
              Re: 1957 LED Ahem A Rivet's Shot <steveo@eircom.net> - 2015-12-11 18:34 +0000
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-11 14:49 -0500
                Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-11 15:39 -0600
                Re: 1957 LED Bob Eager <news0005@eager.cx> - 2015-12-11 22:46 +0000
                Re: 1957 LED Michael Black <et472@ncf.ca> - 2015-12-11 19:07 -0500
                Re: 1957 LED Bob Eager <news0005@eager.cx> - 2015-12-12 01:04 +0000
                Re: 1957 LED Ahem A Rivet's Shot <steveo@eircom.net> - 2015-12-12 08:54 +0000
        Re: 1957 LED hancock4@bbs.cpcn.com - 2015-12-11 11:52 -0800
          Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-11 15:46 -0600
            Re: 1957 LED Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2015-12-11 22:56 +0000
        Re: 1957 LED "Charles Richmond" <numerist@aquaporin4.com> - 2015-12-11 15:35 -0600
        Re: 1957 LED Quadibloc <jsavard@ecn.ab.ca> - 2015-12-13 07:51 -0800
  Re: 1957 LED Lawrence Statton <lawrence@senguio.mx> - 2015-12-10 17:09 -0600

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