| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 1305.1 | more specs, please | BRAT::RYDER | perpetually the bewildered beginner | Sat Mar 23 1991 06:06 | 7 |
| Topic 938 is related to your request, but let's explore your specs.
>> The only specific requirement is that OFF must really be OFF, 0.0 volts.
How close to zero? 0.000001 ? 0.0000000000001 ? 0.05 ?
Tell us what is being done with the output of this device.
|
| 1305.2 | Graupner makes On/Off switch | HPSPWR::WALTER | | Sat Mar 23 1991 13:02 | 18 |
| Graupner makes several ON/OFF controls. I have a Graupner Power Switch 20
in my Challenger electric sailplane. It's designed to switch 20A from a
7 cell battery. No specs for ON resistance, but I know it uses a simple
relay to do the switching, so the ON resistance is probably quite low,
and when it's off, it's OFF.
The Power Switch 20 includes a battery eliminator circuit so you can
run your flight pack off the same batteries as the motor. Graupner also
makes a cheaper switch which does not include the BEC. Hobby Lobby
carries Graupner stuff. My Fall '90 catalog lists the following prices:
Power Switch 20 $53.50
Power Switch 25 $61.40
ON/OFF Control 25 $29.90 (no BEC)
Mini-Switch 40 $51.90 (no BEC)
Dave
|
| 1305.3 | Other Source | LEDS::COHEN | So much for Armageddon! | Mon Mar 25 1991 09:27 | 1 |
| Astro also makes an inexpensive On/Off switch.
|
| 1305.4 | | CLOSUS::TAVARES | Stay low, keep moving | Mon Mar 25 1991 10:17 | 10 |
| You didn't state if you wanted a single switch, or a
multi-channels. However, your local hardware store has a remote
control switch for operating a single device (like a lamp) by
radio. It uses a small hand held tx box that operates on, I
think, the CB band. Its range is about 50 feet.
The switch can be interferred with by citizens band, but
the interferring tx has to be close by.
You plan on blowing up anybody I know?
|
| 1305.5 | 5,4,3,2,1, Blastoff | SNAX::SMITH | I FEEL THE NEED | Mon Mar 25 1991 12:38 | 6 |
| Re -1
My guess is the switch will be used in a model rocket application.
He'll need a range of much greater than 50 feet.
Steve
|
| 1305.6 | Model Rocketry - Worlds Fastest Hobby! | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Mon Mar 25 1991 14:55 | 24 |
| .5 is correct! I'm actually looking at two applications.
One is the launcher itself. In dealing with higher power models,
the wires start getting rather long. Also there are times I want
to head downwind before launching. Seems like a good use for one
of my RC systems. The positive off requirement is due to ignitor
sensitivity. Some of the ignitors are very sensitive - the
continuity check of a typical launch system can set them off.
While 1-2 ma leakage might be safe, 10 would be questionable, and
50 a disaster!
An interesting side question. If this is on the ground, would a 72
MHz system still be legal, or would I have to use 75? Maybe I'll
sidestep the problem and stay on one of my old 53 MHz systems.
The second application is definitely airborne. I'd like to
remotely be able to activate an ejection system on a model while
it is decending. At high altitude I'd deploy a drogue chute. As
the model nears the ground, I'd use the RC ssytem to deploy the
main chute. The goal is to limit the required chase after the
flight. Maybe I could come up with an RC steerable chute :-)
I'll check out the stuff listed in the previous replies. Thanks
for the pointers.
|
| 1305.7 | Be sure to use PCM!! | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Mon Mar 25 1991 18:02 | 21 |
| Bob,
For either application (chute deployment or launch) you probably
should use a PCM system that incorporates "hold last" failsafe.
It could mean disaster if either function were to operate
prematurely due to even the slightest radio glitch.
This may sound like a prank note, but I am VERY serious.
FM or AM won't guarantee safety in this case. Use PCM or nothing.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Castor Oil!! "
|_____/
|
| 1305.8 | use a safety switch | BRAT::RYDER | perpetually the bewildered beginner | Mon Mar 25 1991 18:50 | 9 |
| I'd go a step further and put an arming switch in series with the
launcher signal with ten feet or whatever of twisted pair to the
switch. Then a radio glitch might ruin the flight, but it wouldn't be
a safety hazard.
I did not enjoy the video showing the guy arming the pyrotechnics in
the Zero models.
Alton, who used to have [and use] a dynamite license on hay field rocks
|
| 1305.9 | Safety Switch is standard | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Mon Mar 25 1991 19:31 | 13 |
| A saftey switch (or "key") in series is standard equipment and in
fact required by the NAR(?) which is similar to the AMA.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Castor Oil!! "
|_____/
|