[Land-speed] Shoestring Speedtiming

[neil at dbelltech.com]

Bobby;

You might be able to build a decent timer by using an electronic frequency
counter in a "start- stop" mode. Two photocell beam breakers plus a huge
roll of wire would complete the system. Read out the time and then push the
"reset" button.

You can find counters on the surplus market and on eBay. The photocell
sensors can also be found there. The sensors would be called a "beam
breaker" or something like that. The most convenient type would use a light
beam projected to a reflector on the other side of the track. This
eliminates having to have wires crossing the track for separate projectors &
detectors.

Make sure the detectors are fast enough to give you the accuracy you need
for this application.

Regards, Neil   Tucson, AZ


-----Original Message-----
From: land-speed-bounces+neil=dbelltech.com at autox.team.net
[mailto:land-speed-bounces+neil=dbelltech.com at autox.team.net] On Behalf Of
bobbyhotrods at comcast.net
Sent: Saturday, May 03, 2008 4:55 AM
To: Landspeed
Subject: [Land-speed] Shoestring Speedtiming

After months of pursuit without being knocked out of the box, we, (Bwana and
I), are getting closer to being able to stage LSR time trials at the former
Loring AFB in northern Maine this summer.
It's a great venue at almost 14,000' by 300' of asphalt at 750' above sea
level. Caribou, Maine is nearby so it's not without amenities, and
Interstate 95 is an excellent road getting there.
There is a problem of course, inasmuch as there's hardly any racers or
racecars in this part of the world. 
"If you build it, they will come". We'll see.
So we're on a budget with a capital B. A particular variable cost is timing
equipment rental. At this point getting a high quality system might not be
the best way to spend money. You list guys we'd bet might be able to come up
with a system that while not super accurate, might work fine to give the
three guys that showed up an idea how fast they just went.
Not above soldering something together on a breadboard, etc..
Thanks alot. The Bobbys

http://en.wikipedia.org/wiki/Loring_Air_Force_Base
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