tedwaltman wrote:Seems like a good idea. But don’t those random nuisance calls trigger it?

I read several of the links above and most of them said that you enter the phone numbers that you will call from and it will only accept a call from those numbers. All others it will automatically block!

CW

I'd consider something that allows you to query the status, as well as having the remote unit send replies at start-up and shutdown. One thing I'm looking at is the AT&T Internet Of Things starter kit. Not quite as cheap as a burner phone but it has much more utility.

https://marketplace.att.com/products/at ... tarter-kit

Hook that up to a 10-amp relay module and you can control as many AC circuits as you have relays.

tedwaltman wrote:Seems like a good idea. But don’t those random nuisance calls trigger it?

They can, depending on the phone you use, as noted by clippwagon. I'm no phone expert but these days it seems most phones will allow you to block anything except what is in your contacts list. I'm now close enough to the hangar and in line-of-sight, so am working on putting in a radio link instead of the phone.

I have used very similar GSM relays (7 relays on the box actually in these models) to control my irrigation, and some other light duty switching chores.
They have performed as flawless as anything else with a CPU.

Before a person invests in one, they really need to decide whether their region is better served by GSM or CDMA.

The box I prefer has one 'primary' relay that is activated by a phone call, and 6 others that are activated vis text. The whole enchilada is ran by pretty rudimentary code, but there are many apps available to allow you to custom tailor a 'keypad' with custom buttons, that allow a single pushbutton to send a predetermined code.

As to the security or accidental activation, these are bomb proof. First of all, it has caller ID and will only accept commands from pre approved numbers. Second of all, every command is prefaced with a password, so that even the right phone number has to get the key sequence right to do anything. Of course you do lose some of that particular piece if you make a custom button that sends the entire code.

The call operated relay doesn't actually take your call, so there is no charge there. It simply recognizes your number, hangs up on you, and opens (or closes) the relay.

The text ones, simply use a text message.

All relays can be set up 'latching', timed, or momentary. In the timed function, the time parameters can be in milliseconds, seconds, minutes, or hours. This is a very handy feature, because using this means you don't have to make two calls / texts to turn something on and then off. In fact, once the first action is sent, the rest happens whether you are in a cell service area or not (because the timer has already been tripped).

And yes, when the box actually receives a command, it will send you a text stating what command it has performed. It will also allow you to query it's signal quality, and several other things.

I actually use the phone relay on one of these to fire a starter solenoid, so they take a pretty big hit, and do just fine.

The cost of the plan is almost nothing, I put $100/yr on the card, never pay in between, and always have money left. I just want it to never catch me by surprise, so pretty simple insurance.

Finally, our strip is off grid, so I also use some pretty nifty 12v timers, that can be programmed every which way imaginable, and they are the size of a postage stamp. One of those could be set up to run a heater no sweat, and would have NO cell phone umbilical cord.

Take care, Rob

I have been using it for a year, no problems so far

For those of you that are somewhat adventurous and geek'ish, I am sure there is a Raspberry Pi solution out there. There seems to be a RPi solution to most everything else.

TD

I use an LTE hotspot and wifi controlled power outlet. My reiff heater is plugged into the outlet, and I have a little cabin heater I control off a second one too. The LTE service, up to 500mb, is free after you buy the router. I used freedompop. It works great but you need to be very careful with extraneous charges. You have to diligently cancel all the "free trials" they offer you on sign up it otherwise you'll find yourself paying 20/mo or so.

https://www.freedompop.com/


The outlet comes with an app and is easy to set up:

https://www.amazon.com/gp/product/B075G ... UTF8&psc=1

Total cost = $40

router + one outlet + $5 LTE sign up fee

L-19 wrote:I leave mine plugged in most of the time during periods where I anticipate flying regularly. If I know I can't for a few weeks I leave it unplugged. Electricity is cheap. Just got this email yesterday, makes perfect sence to me. A timer or gsm switch is better than a cold start, but what if you end up not going?

Aviation Consumer actually did a little experiment, testing that long held belief. Guess what, their results contradicted this. They found that the longer the block heater is on, the drier it gets inside the engine. They did leave the oil dipstick opening uncovered.

Sorry Larry, but we have done a lot of cold room testing (granted they were liquid cooled diesels not air cooled lycs) and we found the same thing Orest wrote about below. We tested block heaters, sump pads, heated dipsticks and combinations of all three. We tested in extremes down from -20C to +5C at various humidity levels and winds up to 40 mph. Units were cycled through allowing to cold soak, and then heated 1,2,3,4,5 and 6 hours prior to start. After starting units were brought-up to temp and allowed to run at both idle and under full load for 1 hour. Units were then tested under same conditions only heaters were left on when engines were shut down.

Considerably more condensation was measured inside the crank case, and combustion chambers in the engines that were allowed to cold soak and plugged in only prior to start.

When the heaters were left on (and breathers were kept clean) the engines were for all intents "dry". It was an interesting test that proved a lot of "expert" engineers to be dead wrong.

.

Without explaining how the test works, they are better not to make any claims at all. Highschool Science 101.
It would be easy to do the test badly and get the wrong conclusions, especially if they have a bias.

I bought a two channel Waferstar 3G GSM relay switch for about $140. The only wiring required was adding power and relay outputs. Took about an hour. I used T Mobile, bought a SIM card for about $10, and bought a 10$ pay as you go card. The pay as you go is good for 90 days, so it costs me about $3 a month to run it, and that includes 30 texts. More than 30 is $0.10 each.

The device is set up to only accept calls or texts from a 'whitelist' of approved numbers. If the number isn't on the list nothing happens.

It can be turned on in two ways.
1) An approved number calls the switch and lets it ring for at least three rings. This turns on relay #1 for a programmed amount of time, up to 18 hours. There are no charges on the phone since it never answered. I thought i would like this, but exclusively use the text method below. The approved number could be a landline.

2) Text the device a code telling it which relay to turn on and for how long. I like this for a couple of reasons. First, it texts you back, letting you know it got the message. Second, I can independently control relay times, and add a delay. This lets me turn on the first switch (engine heater) the night before, and a cabin heater an hour before I go flying. It will also text when the relays turn off.

I've been very happy with the switch. Setup was a bit of a challenge, but now it just works. I'm glad it isn't on all the time for a number of reasons.

My SwitchBox seems to have quit working. It may be because it was based on 2G technology that has been phased out of my area. The thing was finicky to say the least anyway, so not sure I want to replace it with a newer version. I hate the prepaid T-Mobile plans too. I was either out of minutes, out of time, or both. And I never knew until I drove out the the plane to fly and it was as cold as an ice cube.

Has anyone been having success with a T-Mobile Hotspot combined with a wifi outlet? It seems the tech has advanced since I last considered this option.

Alex

There are some simple options out there that work pretty well for this, I am using a Wifi smart switch from Lowes https://www.lowes.com/pd/Enbrighten-Enbrighten-Wi-Fi-Plug-in-Outdoor-Switch-2-Outlet-Black/1003202048 and the wifi is provided by a small 4G wifi puck. A couple of us share the cost of the prepaid sim card in the puck and it covers a whole row of T hangars. I have seen 4G prepaid for as low as $10 bucks a month.

I have whats called a SMS switch that works very well. I just went to the company's website to get the link but it is no longer available.
Its from te 5G store. I emailed them to ask what they had for a replacement and will update when I hear back.

Switcheon is an option I have seen advertised. The only downside that I saw was they appear to have a dedicated SIM service that runs on Verizon. $50/year contract which is not bad. I rarely would need one of these units more than a couple of months a year due to not having use of the plane generally the whole winter (wife needs to travel south for a month or two).

I was going to investigate and see if this unit could be used on one of the 'Pay as you go' networks. Due to weather and other issues, I rarely get up more than 2-3 times a month during the winter. For those times I plug it in, run errands and preflight. Generally in a couple of hours the engine is warmed up.

I recently got a data only sim card, threw it in an old cell phone acting as a hot spot and a $30 smart power strip has solved my effort for remote heat. The data card was free so I'm pretty happy with the setup. I was previously using the GSM pay as you go text message setup, but my cell switch stopped working. Attempted to get a new one, but couldn't get it to work on modern cell networks, so happy to find a viable solution that essentially costs nothing beyond the power strip.

On a somewhat related subject, I have been using this remote controlled (100' in my case, direct line of sight) power outlet this winter to pre heat my car's interior, using a 1500 watt electric space heater. The car is in a unheated pole barn, and being a Prius AND living on a mountainside with a 1200' descent, car heat takes a while, starting off at 60-70 degrees makes all the difference comfort wise. !00' isn't far, but when it's blowing 30 MPH, there are 3' deep drifts, and it's 5 in the morning and no coffee yet, it's too damn far!
https://www.amazon.com/gp/product/B07VS ... UTF8&psc=1

My brother and some of his buddies use Switcheon, they are very happy with the unit. I dont know any details, all I know is they are all happy with it.


Kurt

Very happy with the Switcheon. Plug and play. I can’t imagine an easier way to do this, and it works in an area where I have very limited cell coverage.

I've had Speedtalk SIMs deployed in a dozen devices, both off the shelf and custom, for various purposes, including at the hangar. They seem to have worked just about anywhere there is service within around 600 miles of here. $5/month for each line of service. Easy peazy.