[ExI] old software fun

spike spike66 at att.net
Tue Jun 2 05:07:26 UTC 2015

>... On Behalf Of Mike Dougherty
Subject: Re: [ExI] old software fun

On Mon, Jun 1, 2015 at 9:35 AM, William Flynn Wallace <foozler83 at gmail.com>
>> I bought a PC Junior around the early 80s.  It came with a plug-in 
> called Managing Your Money, by Andrew Tobias...
> You are four years old and you smoke?  Are you crazy?  (verbatim).

>...I ran an emulator for a TI99/4a so I could re-live the game "Tunnels of
Doom" it was originally a cartridge but the game saves were stored on
cassette...  Mike

Since you guys are telling old timer stories, do indulge me.

In college the Apple 2 just came out.  A game called Apple Panic was the hot
setup.  I went looking around and found you can still play Apple Panic
emulators online.

Several years later I had a job working as an instrumentation guy.  We had a
data logger which dated from about the early to mid 1980s, still in use in
the early 90s, even though we were starting to phase out the old units.  The
data loggers held 64k data points on each channel, and the device had 12
channels sharing a power source.  The whole thing together weighed about 30
pounds.  You had to do your own signal conditioning, so you would set up
your thermocouple for instance, arrange some op-amps to get voltages 0 to 5
volts, then the 12-channel would log the data according to your

The unit cost about $25k back in the mid 80s, which would get you a really
nice high-end car with all the trimmings, one of them furrin rigs even.
$25k was a fully decked out Lincoln or Corvette.  Even then, channels
sometimes failed, so we would often duplicate the critical channels.  But if
you have fooled with K type thermocouples, you know those bastids can be
flakey, so if one failed, it wasn't always clear which one was the liar, so
you really needed a third channel.  So a quarter of your $25k instrument was
occupied just getting one critical data channel.

Fast forward 30 years.  Now we have these 15 dollar temperature data
loggers.  I bought one, but haven't used it yet.

It has me thinking.  Back in the day, I thought how cool it would be to have
a data logger at home, all the fun things I could measure and log.  Now I
can have a handful of them.  So now my challenge is to get one which logs
the old fashioned 0 to 5 volts, then I can set up my instrumentation to log
whatever I want.

I already have an application in mind: get a microphone, set up some op
amps, filter it to center around 240 Hz or a bit higher.  A bee's wings
sound to me like about third octave B.  (Hey, is that how bees got their
name?  When they buzz around, it sounds like third B?)  Then we could rig it
to trigger a data point whenever the microphone reached a threshold
equivalent to a hovering bee 10 cm away.  Then if we could get those cheap
enough, we could create a standard instrument for 20 bucks or so which would
count bees.  That would be way easier and cheaper than anything else I have
thought of.  Other bugs are different pitches, so we could band-pass filter
the signal from about 230 to about 250 Hz.

Alternative: just take data points every second with the microphone in the
local bee playground, log the intensity of third B.

Next I need to find a good cheap 0 to 5 volt data logger that plugs into a
USB port.

I can think of a buttload of cool applications around the home.

My friends, we are at the party.


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