Yet still another APRS tracker
At the Santee Swapmeet last Saturday, I found a Garmin GPS-18LVC Hockey puck GPS for $40 so I bit on it. Not that I needed it, but I might have a use for it someday.
As the week progressed, I thought about the long defunct tracker I had installed in the wife's Camry. It used a KPC-3, Yaesu Radio and an old old Trimble Mushroom that puts out GGA data only. I ordered another Tiny Track 3+ from Byonics and began to design a new tracker for the good wife's car.
The TT3+ interfaces perfectly with the GPS-18LVC, and supplies the 5V needed for it.
But it isn't that easy. Alot more goes into a Tracker than just having the thing hooked up. One thing I like is to have the GPS come on a few seconds after the auto engine starts so that there is no possibility of starting spikes messing with the equipment. So I designed a DELAY unit which waits about 3 seconds before enabling the +12V to the Tracker. I also like the Byonics method of turning on the radio a few seconds before the tracking transmission and then turning the rig off. They supply only a 5V logic signal to do that, so I added a 2nd relay for that application. A switch on top of the relay box selects either continuous or battery saver function.
Now it was time to wire up the Tiny Tracker 3+, but I like it in a shielded box with lights and switches. So the LEDs and associated switches were brought out to the
front panel. The Switched and delayed 12VDC is fed through a pass through hole between the boxes. Notice the Aluminum tape completely sheilding the inside of both boxes.
The box front panel was labeled and painted, and held down to the top of the Yaesu FT-230R radio with doublesided tape.
here is the completed tracker ready to go in the car
HOWEVER, when I went to program the PIC CHIP in the TT3+, I found the chip had a trashed EEPROM and would not program. RATS!!!! Now I have to get a new IC from BYONICS, hopefully at no cost.
So I will be delayed from further testing until the new IC comes in. But everything works otherwise.
Today I received an updated program from Byon at BYONICS and tried it out on my laptop. Previously, I was trying to program it with my work computer using a standard Serial port. But there must be something fishy about it as my Laptop using the USB to Serial port worked just fine. I was able to read and write several times, so the chip works OK after all. Sorry to Byonics for inferring they had sent me a bad chip; just something very VERY fishy with my work Computer serial port!
I programmed it up for KB6RCT-9 and put it out on a cart in the parking lot. The first thing that happened was the RF from the antenna recycled the power on the Tracker. So RF IS getting through the excellent job of shielding I did on the Tracker. But, I will have the antenna on the outside of the car, and the tracker inside the trunk, so hopefully it won't be a problem. Now I hafta reinstall the whole works back in the wife's car so she will be ON THE AIR with APRS, wherever she goes.
APRS saved us dearly one time. I was up at HRO and they had an APRS monitor station running there. I noticed my wife's car was continuously putting out a beacon from one spot That was curious so I had to call her up and ask WTF? It seems she had LOCKED her keys in the car with the engine running in a parking lot, so I had to come rescue her! APRS saved the day!
I will note that I had the SAME PROBLEM with the new Tracker I just built for the Town Car as I did the KB6RCTmobile. It comes up with an EEPROM error. So I had to program it on the Laptop. For some reason, the program doesn't like Windows 2000, which they make me use at work. Sucks. Doesn't work with the new Arduino either. But they want me to use the computer for COMPANY stuff which DOES work on Win2K. Sucks.