At 07:10 PM 3/22/02 +0000, you wrote:
>I am currently working on modifying a digital countdown timer to plug
>into the remote of a Sony Minidisc so that I can setup a record
>station in the afternoon to start recording in the morning.
>
>I will kick myself for spending the time building this if it is
>already avail. for cheap.
>
>Anyone know of one? Please don't tell me just to order a bomb timer.
>
>Rich Peet
Rich:
Amusing, since my wife Nancy and I just re-read Dave Barry's hilarious "Big
Trouble". Anyway, I say time spent inventing is never a waste - so I keep
telling myself, anyway. Sounds like you have a good thing. I know of none
available easily.
Back in 1982, I used radio shack Minnisette 9 cassette recorders to help
"inventory" migrants by song in several locations. At each site, I set up
the night before the recorder and a fresh tape, wrapped securely in a
plastic bag, tied with several twist-ems around the mic cord. Each had a
$30 Sony omni lavellier mic, hanging higher in a tree, above.
How did each recorder know when to start? Each recorder had, in those
days, a "remote" jack, which has a normally-closed on-off line switch, made
open whenever some mini-plug is plugged in. The plug connections then get
4.5 v DC which needs to be shorted to start the recorder.
The plug wires I brought up about 6 inches above the recorder to a tiny
LASCR - Light-Activated Silicon Control Rectifier (about $3 with
mini-plug). Essentially, at or near first light, well be fore sunrise,
enough light penetrated the plastic bag and triggered the gate so the SCR
latched on for the rest of the day. This started the recorder. As a crude
time check, I knew when a train went through each study area during this
dawn period, so noted the whistle and calculated back to start time.
I bought about 10 LASCRS, and tried morning start times under various
circumstances with 5 volt load. Then, I used the closest matching three or
four. Obviously they all had to set up in the dark, and very carefully
with the darn flashlight!
That was how I met my first Mourning Warbler, actually, when I realized
there was one bird in one morning tape that I didn't recognize. The next
day I was back before dawn with my parabola, despite the two hour drive
from home.
my very best,
Marty Michener
MIST Software Associates
75 Hannah Drive, Hollis, NH 03049
coming soon : EnjoyBirds bird identification software.
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