Posted on

KIM I/O and KX3 Band Decoder Shield ordered

I finally finished some updates to both boards and sent out for boards to be made.  The I/O board might need some fine tuning once it arrives but the band decoder should be all done at this point.

The KX3 band decoder project has functional software that we’ve used in our shack for a few months now, but there was one missing feature that’s been slow to get finished.  The 16×2 LCD limits how user friendly the UI is, so that’s taking some fine tuning.  Source code will be available for download and we’re hoping someone comes up with some better ideas and shares them.


Posted on

Happy New Year!

So it’s been a whole month since I posted anything, but things have been busy here behind the scenes and I simply didn’t get around to doing any updates in a while.

This is the prototype shield for the KX3 Band Decoder project:


A few more connectors need to be installed and then testing can begin.  About a month ago the matching driver board was done, so this shield is the last piece.  Speaking of the driver, I wanted an easy way to test production boards, so I built a one-off test jig:

web_3The board on top is the tester, while the lower board is the driver that is part of the actual product.  Power is on (the red LED) and pin 4, 40 meters, is currently selected (green LED).  In a final version, the driver is mounted with the DB-25 mounted to a rear panel.

What else… oh, the green house monitor!  We’ve had a monitor in Sui’s greenhouse for years now, but it draws a lot of current and the only working version isn’t in the workshop where I can add features, so I designed an Arduino shield that’s much simpler, has smaller code, and generally a better design.  This will turn into a product eventually but for now this is the crude packaging I’ve been working on for our version:

web_1The rear panel has inputs for three analog channels, one for measuring the output voltage of the solar panels, a one-wire interface for external temperature sensors (DS1820), and a connector for the SHT-11 temp/humidity sensor for use in the greenhouse.  There is also an analog channel for monitoring the input voltage to the controller so we can remotely track the solar panel output versus the battery state.

Every few seconds the display moves to the next set of values to display.  The sensor is sitting in the workshop right now, which explains the 67 degree reading even thought it’s below freezing outside:

web_2A new 60K RAM board for the KIM-1 has been sitting on the bench for weeks now; so much for my plans of building/testing over the holiday vacation.

Yes, there are a lot of things on the bench, and we’re starting to make headway finally!

Posted on

Band Decoder for KX3 Project

We’ve have KX3 sn 1418 since August and have taken it on camping trips with the Boy Scouts and had it set up for emergency communications during Hurricane Sandy.  Being spoiled by always having Top Ten band decoders, I needed something similar for the KX3.

Note: For those readers who aren’t ham radio operators, this product is probably of limited interest.

I’ve had a complete decoder working for months already, all breadboarded based on an Arduino:

Kind of messy, but it works 😉  I usually run DX4WIN on my logging computer so the Arduino just sniffs the line looking for IF data and decodes the band from the current radio frequency.

This is a multi-step project, the first being to replace the driver that goes to my antenna switch with a new PC board:

That works great!  It uses and I2C port expander to control 14 output lines on the female DB-25 connector, so it just replaces the Top Ten decoder; same connector.  The board also has a 12-to-9 volt regulator (not solder in place yet in the picture) to give 9v to the Arduino’s VIN line.  The I2C connector is one of those small TE connectors used on all the GROVE boards.  We’ll be introducing more boards with these connectors and will stock the connectors and cables.

The DB-25 simply pulls one or more of 14 lines to ground.  There is also GND and +12 on two pins, making this board potentially useful for controlling many things besides antenna switches.

The UI is done completely with a 16×2 LCD and a rotary encoder.  The user can select the baud rate of the interface, manually or automatically select bands, etc.  The next step in software is to allow for driving specific bits on the interface rather than predefined band codes.

The next step will be a board that is either a standard shield that simply plugs into an Arduino or a stand-alone board with the remaining logic.

I’m not sure if this will become a real product or just an experiment, but if you’re interested, let me know.