WD4JKH
Member
I got a new bicycle to hopefully help me shed a few pounds and for some reason I thought it would be fun to put an APRS tracking unit on it. Granted the bike isn't a Trek or a Cannondale but I didn't want to spend a lot of bucks on a bike if I didn't stick with it. I already had most of the items needed so it didn't involve much expense to put the tracker on it.
For those not familiar with APRS, it basically is a way to track a vehicle using ham radio. GPS data is fed to an interface which connects to a radio which transmits its position information on the standard frequency of 144.39 mHz (US). These transmissions are (hopefully) heard by stations set up by hams to either relay the data packets or gate them to servers on the internet. Anyone can go to an aprs site such as aprs.fi, enter the call sign of the unit and see where they are and where they have been. Other info such as speed, altitude and heading may also be available. The good part is the system is free to use by licensed hams but the bad part is that there is no guarantee that your data packets will be heard and gated to the internet.
I decided to use an older Magellan GPS receiver that I had and I was able to pick up a handlebar mount for it from ebaY. Using this GPS receiver serves two purposes in that it puts out the NMEA position data for the tracker plus it serves as my speedometer, odometer, etc. The cradle it uses is a snap in type that connects to the serial/external power cable that runs to a box on the rack behind the seat. The snap in mount makes it easy to pop the unit out and put in my pocket if I walk into a store.
I bought a Pelican case to mount on the back rack. I tried to get one as small as possible but still get in everything I needed. I had a 12v, 7AH gel cell that I wanted to power the radio, GPS receiver and an extremal light I put on the back. The battery and radio are in foam cutouts plus have some velcro straps to hold them in place. The radio is an older GE PLS model portable. If anyone has seen my mobile set-up on my run-around Blazer, you know I have a soft spot for 'classic' GE stuff. That link is here under my old moniker: <a href="http://forums.radioreference.com/pictures-your-shack-mobile-setup/125555-1987-s-10-blazer-3-radios.html" target="_blank">1987 S-10 Blazer with 3 Radios</a>
The little box velcroed to the top of the battery is the Tiny Trak from Byonics. It controls the radio to transmit data packets from the GPS receiver info. I made up this box several years back to use portable in a backpack and it worked quite well. It has its own 9 volt battery inside so I decided to leave it as it was in case I wanted to use it for a hiking trip. Besides, the 9 volt battery seems to last forever.
There is a switch on the outside of the box on the left front side that will turn off power to the radio battery eliminator and the GPS receiver. There is a cable connected to the battery that comes out the bottom with a connector that can be plugged into an AC charger. I found a small cheap solar panel at Bass Pro Shop that I velcroed to the top of the box and plugs into the connector when the AC charger is disconnected. The solar panel will not put out enough to run the equipment but my hope was that it would keep the battery from running down as quickly. I have found out that it puts a pretty good trickle charge on the battery from the ambient light coming through the windows on my shop. I have only had to use the AC charger once.
The antenna is a dual band mounted on a plate attached to the bike rack. It uses a standard NMO mount so I can change it out with a 1/4 wave if I want to be a little less conspicuous. The dual band seems to get out better so I use it most of the time.
If anyone is interested, the call sign for the bike is wd4jkh-4. <a href="http://aprs.fi/?call=wd4jkh-4&mt=roadmap&z=11&timerange=3600" target="_blank">Use this quick link.</a> I haven't ridden much lately but the aprs.fi site does archive position points of past dates.
This setup isn't for voice but if I want to monitor ham or public safety, I'll put my little Yaesu VR-120 or Icom IC-07A in my pocket when I ride.
For those not familiar with APRS, it basically is a way to track a vehicle using ham radio. GPS data is fed to an interface which connects to a radio which transmits its position information on the standard frequency of 144.39 mHz (US). These transmissions are (hopefully) heard by stations set up by hams to either relay the data packets or gate them to servers on the internet. Anyone can go to an aprs site such as aprs.fi, enter the call sign of the unit and see where they are and where they have been. Other info such as speed, altitude and heading may also be available. The good part is the system is free to use by licensed hams but the bad part is that there is no guarantee that your data packets will be heard and gated to the internet.
I decided to use an older Magellan GPS receiver that I had and I was able to pick up a handlebar mount for it from ebaY. Using this GPS receiver serves two purposes in that it puts out the NMEA position data for the tracker plus it serves as my speedometer, odometer, etc. The cradle it uses is a snap in type that connects to the serial/external power cable that runs to a box on the rack behind the seat. The snap in mount makes it easy to pop the unit out and put in my pocket if I walk into a store.
I bought a Pelican case to mount on the back rack. I tried to get one as small as possible but still get in everything I needed. I had a 12v, 7AH gel cell that I wanted to power the radio, GPS receiver and an extremal light I put on the back. The battery and radio are in foam cutouts plus have some velcro straps to hold them in place. The radio is an older GE PLS model portable. If anyone has seen my mobile set-up on my run-around Blazer, you know I have a soft spot for 'classic' GE stuff. That link is here under my old moniker: <a href="http://forums.radioreference.com/pictures-your-shack-mobile-setup/125555-1987-s-10-blazer-3-radios.html" target="_blank">1987 S-10 Blazer with 3 Radios</a>
The little box velcroed to the top of the battery is the Tiny Trak from Byonics. It controls the radio to transmit data packets from the GPS receiver info. I made up this box several years back to use portable in a backpack and it worked quite well. It has its own 9 volt battery inside so I decided to leave it as it was in case I wanted to use it for a hiking trip. Besides, the 9 volt battery seems to last forever.
There is a switch on the outside of the box on the left front side that will turn off power to the radio battery eliminator and the GPS receiver. There is a cable connected to the battery that comes out the bottom with a connector that can be plugged into an AC charger. I found a small cheap solar panel at Bass Pro Shop that I velcroed to the top of the box and plugs into the connector when the AC charger is disconnected. The solar panel will not put out enough to run the equipment but my hope was that it would keep the battery from running down as quickly. I have found out that it puts a pretty good trickle charge on the battery from the ambient light coming through the windows on my shop. I have only had to use the AC charger once.
The antenna is a dual band mounted on a plate attached to the bike rack. It uses a standard NMO mount so I can change it out with a 1/4 wave if I want to be a little less conspicuous. The dual band seems to get out better so I use it most of the time.
If anyone is interested, the call sign for the bike is wd4jkh-4. <a href="http://aprs.fi/?call=wd4jkh-4&mt=roadmap&z=11&timerange=3600" target="_blank">Use this quick link.</a> I haven't ridden much lately but the aprs.fi site does archive position points of past dates.
This setup isn't for voice but if I want to monitor ham or public safety, I'll put my little Yaesu VR-120 or Icom IC-07A in my pocket when I ride.