I'm not an electronics guy, but on my reading of your instructions, I feel I could build this! And the price is definitely right.
A question/suggestion: could a mechanical thermostat (possibly Luxpro PSM30SA, approx $13) (http://www.luxproproducts.com/thermostats_mech/psm30.htm) be inserted in the line along the 110V power adaptor? Set it at, say, 85 degrees. When RV gets too hot, thermostat opens, causes the same alarm as the generator failing.
Yes, anything you wanted to add that could make a connection between the 12v negative and a trigger wire would work. There are 4 trigger wires in the alarm, 2 for the doors, 1 for the hood and 1 for the trunk. I picked the trunk(blue wire). So you could add 3 more things to detect.
I forgot to mention, the antenna is used inside the windshield, I used velcro so I can take it down. The whole thing rolls up and fits in a drawer.
* This post was
edited 07/19/06 10:35am by topless *
dmomberg wrote: A question/suggestion: could a mechanical thermostat (possibly Luxpro PSM30SA, approx $13) (http://www.luxproproducts.com/thermostats_mech/psm30.htm) be inserted in the line along the 110V power adaptor? Set it at, say, 85 degrees. When RV gets too hot, thermostat opens, causes the same alarm as the generator failing.
Adding this fail-safe would be the "piece de resistance" of this project. Detecting a generator shut-down as well as detecting a specific temperature being reached would give me additional piece of mind.
I had the situation the other day after my generator had warmed up where I attempted to switch on the AC. It didn't come on even though the thermostat was set where it should have come on considering the 95 degree ambient temps. I didn't have my dogs with me at the time. So I left the generator running with the AC switched on (but seemingly not functioning) thinking that it would eventually cycle on. It did not come on even after about 30 additional minutes with significant interior temperature increases during that period.
So here was a situation where the generator was running and the AC was switced on but not functioning.
Later that day, after the generator had been off for a while, upon restart, the AC came on.
I too will look into ways of tripping the alarm at a specific temperature.
Thanks Topless for all your GREAT WORK!
PS: I found the Commando Long Range Car Monitor Pager (PG-8) for $10 cheaper plus ~$10 shipping here:Etronics.com
Now you guys got me thinking again, so I ordered a digital temperature sensing switch that will run off of 12vdc. If I'm correct in reading it's description and wiring info, I should be able to trigger one of the alarm wires with this at any temperature between -40 and +140 degrees. Since it will operate on the chassis voltage, I will have 2 seperate ways of making sure my dogs are cool and comfy.
After I get it to work, I'll tell you what I ordered.
As I said in another thread. That is exactly the same alarm and temperature monitor setup I used last year. The problem with that alarm pager is it has very limited range. They claim 1/2 a mile, I couldn't get 1/4 out of it consistently. If I put the antenna in the front, and walked away to the rear, it would not reach 300 yards on flat ground. I quit messing with the thing because the of limited range.
I tried it every way I could think of and the alarm is just not powerful enough to be of any value. By the time I was back in range, I was close enough to check it.
That alarm costs about $60, and the temperature monitor was $15, If you''re going to buy one, I can tell you where to buy the parts and give you a wiring diagram. The box, switches and power cords are from Radio Shack. I had LED's for power indicators.
topless wrote: Now you guys got me thinking again, so I ordered a digital temperature sensing switch that will run off of 12vdc. If I'm correct in reading it's description and wiring info, I should be able to trigger one of the alarm wires with this at any temperature between -40 and +140 degrees. Since it will operate on the chassis voltage, I will have 2 seperate ways of making sure my dogs are cool and comfy.
After I get it to work, I'll tell you what I ordered.
Now that's what I'm talking about!!! Thanks Topless. Next you'll have to market the whole package after you miniturize it!
I'll be very interested in your effective range experiments too.
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