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PIC-E information page

The PIC-E was an elegantly designed general purpose AX.25 encoder kit to build an inexpensive tracker device for APRS.   It came with a very detailed set of assembly instructions and a built-in PIC programmer.  Unfortunately, it's no longer available.  You can still get a bare board and information about it and order it at the TAPR PIC-E section.

I  have interfaced the PIC-E to a DeLorme Tripmate GPS and also to a Garmin 95XL in my plane.  Most APRS applications with the Tripmate require a modification that essentially connects its TX line to its RX line.  You don't  need to modify the Trimpate for use with the PIC-E because the PIC-E has a jumper that feeds the TX line back into the RX line.  This allows the unit to get past the power up stage where it's waiting for the word 'ASTRAL' to be sent to it.   There is also another jumper inside the PIC-E that pulls the Tripmate's DTR line high which is the signal the GPS uses to turn itself on.

The Tripmate is out of production, but you can find some good deals on them on Ebay.  The DeLorme Earthmate is a newer replacement for the Tripmate, but doesn't use the NEMA sentences to communicate its position so it is incompatible with most GPS trackers and TNCs unless you get a 'translator' to convert to NEMA format.  I power the Tripmate through the 5V regulator in the PIC-E.   To do this, I connected the regulated 5V supply on the PIC-E board to pin 9 on the GPS connector. Then I moved the yellow wire  inside the Tripmate to pin 3 of the battery connector side on the Tripmate's PC board.  This will be easier to understand if you view modification page as all the wires are shown there.  I am considering a change to this approach since I've read that the Tripmate doesn't always work properly when powered by 5V.  I am going to add a separate regulator inside the case to provide 6V to the Tripmate which is its intended operating voltage.

If you need an enclosure, the PIC-E is designed to fit into a standard Radio Shack enclosure as described on Steve Bible's web page.

After you build the PIC-E, make sure to visit the TAPR PIC-E software section to get the latest available software.  I found that several important improvements had been made over the original version of the GPS-E-2 program that came with the kit.  Another thing you may notice is that switches SW1 and SW2 work 'backwards' from the way they are described in the documentation.  I think this may be the result of substituting toggle switches for the original slide switches.  In other words, position '1' is to the right and position '2' is to the left.

I would like to add wiring diagrams for various HTs and mobiles to this page eventually, so if you have a schematic or pinout you'd like to send, I'll make sure to post it here.  I am currently adapting some MFJ TNC cables that I use with the KPC3+ for my FT50 and FT51 to work with the PIC-E.  I also would like to interface it with an FT100 and the FT90.

Rick, VE3CVG, provided a text file of all the hex codes for various icon symbols to help you program your PIC-E.  He also made up an excel spreadsheet  (scroll down to the piceinfo link) to help organize the files you'll create with GPS-E-2 program.

Byon  Garrabrant, N6BG,  has completed  the 'TinyTrak' which is a modemless PIC encoder and it is a price/performance breakthrough.  I built one myself in about an hour and it is a truly amazing design that is elegant in its simplicity.  It is a very affordable ($33) encoding device for APRS applications.

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