TNC Using RFM22B / RFM23BP UHF Tranceiver Modules.
- Hi Folks,
As well as the TNC-X based 1200 baud TNC I described in an earlier post, I
have designed a TNC for the PI round the Hope Electronics RFM22B/RFM23BP
modules. These modules include a UHF tranceiver and digital modem. There is
a photo of the board here:
This one is fitted with the RFM22B module, with 100 mW output, but the board
will also take the 1 Watt RFM23BP. Although designed to work with the PI, it
also has a header for a serial to USB converter, so it can be used as a
standalone KISS TNC.
I have been running them on 434 MHZ with a data rate of 9600 baud. For
testing I hooked up an Adafruit Ultimate GPS Breakout board , so I could use
APRS to track the range achieved. Photo here:
I wondered how much use 100mW would be in practice, but the first tests seem
encouraging. With the 100mW version I achieved a range of just under a mile,
with a 5/8 over 5/8 70cms whip on the car, and a far from ideal Marine Band
whip at base. I'll be doing more tests over the next few days woth a better
antenna, and will report back.
BTW, the GPS module is pretty neat as well - it is about an inch square, and
includes a data logger - https://www.adafruit.com/products/746
73, John G8BPQ
- Hi folks.The pi port of BPQ32 is about ready for testing. There are sure to be problems with it still, but if anyone is willing to try it please let me know. At least to start, I suggest testers should be familiar with BPQ32, and have a basic knowledge of linux commands - this isn't really something for those new to either BPQ or linux to play with at this stage.The basic features are:Has been tested on Raspberry PI and Ubuntu running on a PC.BPQ32 compatible Node, includng the APRS Digi/Igate featureUses standard bpq32.cfgDrivers for KISS, AXIP, BPQEther, Telnet, SCS Tracker, SCSPTC. I2C Driver for PITNC on the PI. Others to follow.Includes the BBS part of BPQMailChat (not chat).BBS Configuration and BBS/Node monitoring via a Web interface.The instructions for installing BPQ on linux can be downloaded from https://dl.dropbox.com/u/31910649/InstallingLINBPQ.htm73,John G8BPQ