I want to use an arduino for automatic packet reporting, but I'm having trouble finding a way to generate the 144.39MHz and frequency modulation. I'm not good enough with electronics to get a phase locked loop to do what I want it to do, so I'm looking for a module I can plug into the arduino. All I've found are transmitters in the range of 75-108MHz, for car raidio. Are there pre-made modules available to transmit at 144.39MHz? Is there an easy way to generate a frequency modulated 144.39MHz wave?
Okay, I'm sorry to have to ask this, but the nature of your questions prompt me. Do you hold a ham license?
aarg:
Okay, I'm sorry to have to ask this, but the nature of your questions prompt me. Do you hold a ham license?
I'm taking the test next week. By the time it's usable I'll have a license
Okay, then get yourself a VHF transceiver. It will give you all the functionality that you need, at low cost and high compliance with FCC regulations. Realize that APRS is a network with rules, be nice to it.
You can make short range (1-100 meter) transmitters from a Raspberry Pi, 1-250 MHz, with several types of modulation including FM and AFSK used in APRS. It is essential to add a good bandpass filter between the output pin and antenna to suppress out of band harmonics.
PiFM works for the FM broadcast band. This forum seems to expect one to deliver appropriate warnings about checking the local legality of such operations.
There are plenty of ham network applications and software, check out (for example) TNC-Pi
I was looking into this (Arduino based APRS) too, eventually decided that when I do want to do it I'll get a ready made APRS beacon and not have to fart around with Arduino on this. I don't really see what Arduino brings to the party, other than the fun of making it, of course.
Meantime my son and I beacon from our phones using aprsdroid, as ZS6HMB-5 and ZS6JMB-5 respectively, follow on aprs.fi.
73 and good luck with the ham exam.
$$$!
If you're starting out in APRS, it's really no fun or hands on learning unless you have duplex operation. You only get that with a transceiver. If you really want to connect on the air, the extra transmit power versus what you could home brew, is a real plus. I'm not saying it couldn't be done, or that it wouldn't be interesting. It's just far from a beginner project. Really far.
Easiest way is to hook up to a handheld through the mic/speaker plugs, and electronically trigger the PPT to send the packet.
Or should I say, second easiest: easiest is to buy one off the shelf which is what I plan to do.
We used aprs extensively a few weeks ago, where Hamnet the emergency comms side of the South African Radio League provided comms and roving support for a 120km cycle race. We mounted our 2m rigs in the sponsored trucks for voice comms both simplex to the water points and duplex through the repeaters to race control. Then we made sure each truck had aprs, either through the GSM net like I do with aprsdroid, or with an rf beacon on 144.800 (that's the aprs freq here...). Race control could see at a glance where we all were in case of re-deployment needs.
JimboZA:
Easiest way is to hook up to a handheld through the mic/speaker plugs, and electronically trigger the PPT to send the packet.
It has been many years since I played with APRS. I had the Kenwood TM-700D in my car. It's a transceiver with integrated APRS. I know I was running at at the base station, but I can't remember what I was using there. I'm thinking it might have been a PC with a sound card interface, because I did use that for PSK-31.
How could I plug in a simple handheld HAM to an Arduino? Is thier any easy way? All I need is to ransmit data to the APRS network!
The radio:
@WesleyRTech: How is this post different from your balloon project? Do not hijack threads.
WesleyRTech:
How could I plug in a simple handheld HAM to an Arduino? Is thier any easy way? All I need is to ransmit data to the APRS network!
Well, I've met some diminutive hams, but never one that I could hold in my hand. A few of them were quite simple, though.
WesleyRTech:
How could I plug in a simple handheld HAM to an Arduino? Is thier any easy way? All I need is to ransmit data to the APRS network!
The Baofeng uses the Kenwood style of microphone/speaker plug, and the connections using that are well documented. The ptt is triggered electronically when the packet is to be sent. Google will be your friend here.
How are you constructing the packet, as a matter of interest?
JimboZA:
The Baofeng uses the Kenwood style of microphone/speaker plug, and the connections using that are well documented. The ptt is triggered electronically when the packet is to be sent. Google will be your friend here.How are you constructing the packet, as a matter of interest?
... and the audio, out of interest?