OLD TIMERS LICK MAIL PROBLEM!
Our
mailbox wasn’t handy. It was about a mile and a half from our house on a
larger road that went to the county seat in one direction and another
little town in the other direction. The road wasn’t paved and if it
rained the mail man usually didn’t attempt to travel on the muddy route.
Sometimes it was two or three days before he felt like it was dry enough
for the mail delivery. We had a regular mailbox on the east side of the
road. It was mounted on a two by six that extended from a post to the road
at about the right height for easy access from an automobile.
We subscribed to a daily newspaper but some days we did not make
the trip to the mailbox, especially if the weather was disagreeable. For
several years I was the official mail man. This required me to walk the
three mile round trip or ride a horse. Sometimes the horses were busy
plowing and not available and at other times they were in the big pasture
and locating them and getting them in the pen could easily be more work
than the walk to the mailbox. When I got older and drove a Model T many of
the mail box trips were easier and quicker to make.
The mail carrier didn’t come at the same time every day. Some
days he was early – even as early as ten o’clock in the morning. At
other times he might be as late as two or three in the afternoon. We never
knew why there was so much variation, but if we could know when he was
early we might get the mail several hours earlier. If we wanted to mail a
letter we didn’t know if it was too late.
Although most country folks had abandoned their old telephones,
miles of telephone wire was still strung through the trees and on fence
posts. Our idea was to run a telephone line from the box to the house and
connect it in such manner than a signal would indicate if the door to the
mail box had been opened.
The first thing we would need for such a system would be a
container for the equipment. We decided on a Model T coil box. The box was
made of metal and would be weatherproof. We would need a coil for the high
voltage and it would fit nicely in the container. There would also be room
for a battery and any other devices we needed. We could use an old
telephone call box for the alarm. A little motor from a rotary Model A
horn would provide a nice pulse generator with a cam on the rotor and a
switch connected to make a connection with each revolution. The motors
were designed to operate on 6 volts so our one and half volt battery would
slow it down to about the right speed.
A simple switch on the mailbox door would turn the alarm on or off.
The coil box mounted handily on the board behind the box. A good ground
connection and the connection of our telephone wire finished the
installation. In the house we installed the call bell and devised a little
flag that would fall when the bell rang. If the bell rang when no one was
within hearing distance the lowered flag indicated that the mailbox had
been opened. The flag could then be reset and readied for another opening
of the mailbox.
The system worked very well. When the mailbox was opened the switch
connected the battery to the motor and when the motor turned the
intermittent switch on the shaft connected the spark coil and high voltage
pulses were sent out on the telephone line. At the receiving end the
pulses caused the bell to ring and the flag to fall. We considered this a
real achievement for two young electrical engineers!
Our project was so well promoted that we got requests from several
families with similar mail problems. Since most of the parts were
available without cost we were able to built several alarms and make a
nice profit.
The alarm was used for several months. Eventually the WPA of the
depression era built a road by our house and the system wasn’t
necessary.
Mailbox wireless alarms are available now at a very reasonable
cost. They work on a different principle. When the box door is opened
outdoor light actuates a transmitter that turns on a light and an audio
beeper in the house. In a few seconds the beeper stops but the light
continues to blink and let you know that the mail has come and gone. Push
the button and the light goes out and you’re ready for another mailbox
opening!
Did we have fun building the contraption? Of course – You can
have a barrel of fun building a mailbox yapper!
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