900 MHz RF modules

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Its an audio transmission chip, not data.
 
So was (is) my phone line before I got DSL. I'd be willing to bet you can still push a digital signal over an "audio" link.

Of course you can. But then you will need a separate encoder decoder circuitry and code at each end...
 
Depends on what you wanna use it for I guess.

If you simply want a wireless link for close up, for example wireless programming of a StratoLogger you can simple plug in a serial BlueTooth module to the serial Port for around $30 from places like www.adafruit.com or www.sparkfun.com

I have a pair of the digi XSC 900Mhz moduls and they work great with specs stating good at 28miles LOS with high gain antennas.
https://www.digi.com/products/wirel...dules/point-multipoint-rfmodules/xbee-pro-xsc

There are tons of other Xbee versions that are much cheaper for short distances.
Both of these flavors are just wirelessly extending a standard serial port.
The xbees and Bluetooth are frequency hoping so interference is not a problem with standard 900Mhz.
 
Depends on what you wanna use it for I guess.

'zaktly. These were cheap, looked like they were easy to use, and can do analog or digital (digital *is* analog, btw). Linx sells an RF module they say puts out 1 W into a 50 ohm load. That should go quite a ways, LOS (especially straight up). The long-range balloon guys are getting really good results with their stuff, too. I miss the days when I was working on govt. research projects and could use "reserved" bands and dump as much power out as the batteries would give.
 
Mostly what you want to think about is safety and rules. Both of which you don't want to break/do at a launch or jack up somebody else's tracker or telemetry. Honesly There is something to be said for pre-made modules. The time has already gone into them with detailed instructions. Stuff like what you posted on All-Electronics is surplus mostly and good luck getting info/specs on them with out having to spend tons of time reverse engineering it. I'm a firm believer of KISS. (Keep It Simple Stupid) :)

I have a brand new wireless phone with base station I got from a surplus store with the intentions of using it for a wireless launch trigger/controller. And guess what. It's still sitting in a box in the corner!
 
Speaking of RF, does someone make a stable cost effective receiver with a keybob that has an analog output for making a wireless launch controller?
 
Yes, search ebay for "wireless remote control". Pick 315mhz though. Rockets with 430mhz trackers will interfere with 430Mhz remotes.
 
Hi John,

I've used a coded remote on 433Mhz without issue although 315mhz would be reasonable. Kurt

I have field tested (ok backyard tested) a 433 coded remote with the reciever about 10 feet away from BRB tracker. Similar to a rocket on the pad situation. While the tracker is transmitting the remote would not 'hear' the key fob. So I suppose you can get the remote codes in-between the BRB beeps but the response would not be instanataneous. Worst case, if you have a rack of rockets all with BRB's, there may not be any silent stretches where the RF remote code can get through.

My application was a Hybrid fill GSE. It was very important that I can turn-off the fill valve when I wanted it off.
 
I have field tested (ok backyard tested) a 433 coded remote with the reciever about 10 feet away from BRB tracker. Similar to a rocket on the pad situation. While the tracker is transmitting the remote would not 'hear' the key fob. So I suppose you can get the remote codes in-between the BRB beeps but the response would not be instanataneous. Worst case, if you have a rack of rockets all with BRB's, there may not be any silent stretches where the RF remote code can get through.

My application was a Hybrid fill GSE. It was very important that I can turn-off the fill valve when I wanted it off.

O.K. I can appreciate that. I was concerned about a stray signal setting off a launch prematurely. It didn't but I did not try sending a command to fire while the offending transmitter was transmitting. If you are sending a command to shut off a fill valve, you'd want that to get through, interference or no. Kurt
 
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Look into the HopeRF modules. I like to use the ones that are part of an Arduino clone - the MiniWireless boards from Anarduino. They are nice board and some new models should be coming out later this week.
 
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