Bluetooth Rig Control for $10!

HC-05 Interface Board
The Bluetooth Dongle. Read below for details

If it’s one thing that continually amazes me is the impact Arduino & IoT are having on Amateur Radio. Things that were once complex pieces of electronics with a complex price tag are now commoditised and available for pennies.

When I first started, a CAT rig control interface could cost up to $200, particularly if on-brand. Taking a look on eBay now, you can find a heap of these Bluetooth Dongles that plug into the back of my FT-817 for generally around $12!

Unfortunately for me, the one that arrived is dead on arrival. It did give me an opportunity to pop the cover and see what is inside. there is not a lot to it at all! To the right of the LED in the picture is basically an AMS1117 3.3V regulated power circuit base, with an HC-05 Serial TTL to Bluetooth Module soldered on as a daughterboard. With only 5 pins in use – +ve, gnd, rx, tx, and LED state, very little needs to be done with these units other than connecting the cables at the right places!

My testing of this unit found that the HC05 board is defective. I have confirmed all power is going to the right places, and it is correctly wired, but unfortunately the unit does not broadcast a bluetooth device ID. This is the big catch when buying from eBay – you get what you pay for! lucky for me the seller is willing to send a replacement unit.

I think however I will eventually purchase one of the units made by K6VHF (His eBay store here). Its ridiculously more expensive, but I will get a unit that has been assembled and tested properly by someone familiar with the radios – and given I spent about an hour of my time today troubleshooting the defective one, with unknown quality of the replacement, that may be money well spent.

I’ll give an update when I have a working adaptor!

Rig Control with RUMlogNG

My workspace for my radio gear is pretty limited, therefore space is at a premium. The Toshiba Tecra M2 which I used as my station computer for many years finally reached the end of its life, with none of the major operating systems supporting non-PAE chipsets. Not ready to purchase a laptop just for radio operations, I was hoping that I could use a more contemporary platform for operations – an iPad.

A quick search around and I came across RUMlogNG, which is easily the best logging interface I have seen in a ham radio iPad app that is modestly priced.

RUMlogNG Logging Page

One of the more interesting features was that basic interaction with your radio was possible (reading of frequency, mode), with the suggestion to use one of Pignology’s Piglets. Reading the specifications of the piglet, it became apparent that what it was doing was taking the serial CAT interface of the rig control, and making it accessible over wifi network to connected devices by streaming the serial data out of a TCP port.

Armed with this information, went looking for alternative ways to connect serial interfaces to RUMlog, and happened across this forum post, talking about an app called remserial. After attaching a Serial to USB Converter to a Raspberry Pi, I was able to run the below command as root:

pi@raspberrypi ~/remserial-1.4 $ ./remserial  -p 7373 -s "9600 raw" /dev/ttyUSB0

The app did not crash when I tried this, so I assumed it was running, and then configured RUMlogNG to connect to the Raspberry Pi on port 7373. Success! RUMlog did not throw any errors and back on the logging screen, I saw that frequency and mode was being updated off the radio.

Rig Control with RUMlog