How to set up the client side of the remote radio system.
(under construction) patches have not been uploaded to github
This client works with the sever described in the previous post. We are running a MacBook Pro OSx 10.11.4. with the following:
logmein hamachi VPN
Soundjack VOIP
Max/MSP
Novation launchpad
DJ-Tech CDJ-101 controller
VPN
Install and set up LogMein Hamachi. It is free, for a limited number of computers. Set up a Hamachi server on both the server and client. It should look something like this:
VOIP
We are using Soundjack VOIP. It is also free. Use the following parameters on the client side.
mic: soundflower 2ch (or something that is not currently producing input!)
headphone: default output (or whatever you want to listen on)
You can ignore the rest of the settings, since we are not sending audio. Most of the configuration is done on the server side.
Max
We are using several patches, depending on which hardware controllers you are using. Make sure that the hardware controllers are connected before opening Max.
patches:
eagle-ui5.maxpat – User interface and main entry point for client communication and CDJ-101 abstrations
freqdb4.maxpat – database handler
lp_radio2.maxpat – launchpad driver
After the max patches are loaded, you should be able to control the radio using the UI and the CDJ-101 controller. The red Mixer button in the upper right corner of the Launchpad should be lit.
How to run the server side (base station) of the remote shortwave radio system.
(Under construction) The patches have not been uploaded to github yet.
Assuming that the radio and antenna system are operating. We are using an internet connected MacBook Pro running OSx 10.9.5, with a MOTU 828 MK3 audio interface.
VPN
Install and set up LogMein Hamachi. It is free, for a limited number of computers. Set up a Hamachi server on both the server and client. It should look something like this:
VOIP
We are using Soundjack VOIP. It is also free. Use the following parameters on the server side.
Local Settings:
mic: audio interface channel that is connected to radio audio output
headphone: doesn’t matter
volume: 0
audio block samples: 512
channels: 2
network packet samples 512
quality: high
userlist: manual
User list:
UDP/IP: enter hamachi IP of client.
When Soundjack is set up on the client. Press the green start button on the right side of the user list window on the server.
If all goes well, you should hear the radio on the client. Note: The input meter under local settings should be registering audio from your radio. If not, there is a problem with the audio interface.
Max Server
The Max/MSP server exchanges CAT commands via the server serial port to the radio. The command data is exchanged with a Max patch on the client using OSC (over UDP).
patch:
eagle-cat8.maxpat
instructions:
select the radio serial port from the menu (for example: usbmodem 14531)
initialize port settings
set toggle to poll the serial port
At this point you should be able to try the example commands, for instance to get the version or set frequency. If the commands are not working, it indicates a problem with the serial connection to the radio.
Next, check the IP address of the udpsend object. It should be the hamachi IP of the client.
The first in a series describing a system for internet remote control of a shortwave radio station. Its not something new. There are commercial products that provide remote operation of amateur radio transceivers. The purpose of this project is to make it possible to use shortwave radio sounds in musical performance, without the need of an antenna system.
Features:
Max/MSP for USB serial control of radio, OSC remote interface, user interface, Midi device handling, and an SQLITE database of preset frequencies.
Low latency, good quality audio using Soundjack by Alex Carot.
Hardware control of radio using Midi controllers (CDJ-101 and Launchpad)
Bi-directional OSC and VOIP using Logmein Hamachi VPN
Additional hardware control of AC power and antenna selection using Arduino and a WeMo switch.
TouchOSC Ipad audio mixer control using MOTU Cuemix
TeamViewer remote desktop software for logging into to base station compuer
Optional radio user interface control with Ipod TouchOSC, Griffin Powermate dial, and Korg Nano-kontrol.
How to control an amateur radio transceiver over the internet, using Osc (Open Sound Control), VOIP (Voice over Internet Protocol) and VPN (Virtual Private Networks).
What problem does this solve?
Using a shortwave radio receiver in a live performance without installing a large antenna system.
This method gives low-latency real-time access to audio, and radio control using a laptop computer from anywhere. I suppose it could also remote-control a synthesizer, if you’re into that kind of thing.
CAT
Modern ham radio receivers can be controlled using serial commands using the CAT (Computer Aided Transceiver) protocol. Usually this is done via a USB port. There are hardware solutions for remote controlling radios over the internet, like RemoteRig http://www.remoterig.com/wp/. But there is also a free, or low cost, solution using software.
System diagram
The ‘base’ computer is connected to the radio/antenna. The ‘remote’ computer is a laptop that could be anywhere connected by WiFi
For this experiment we used a TenTec Eagle transceiver connected to a MacBook USB port. The audio output of the radio connects to the audio input of the MacBook. The MacBook is directly connected to an internet WiFi router using an ethernet cable.
VOIP
A mumble client runs on the base computer, https://en.wikipedia.org/wiki/Mumble_(software) and also on the remote laptop. Both clients are connected to a Mumble server (Murmur) at Mumble.com http://www.mumble.com/mumble-download.php. You could also run your own server. I set the audio to the best quality and muted the microphone on the remote laptop. We are only using the laptop as a receiver. For transmitting, you could simply open up another channel on the Murmur server. Mumble has very low latency (compared to Skype) and decent audio quality.
Bi-directional commands using VPN and OSC
CAT commands go in both directions – to and from the radio. For example, you would send a command to the radio to change frequency. The radio would send acknowledgements back to the remote laptop.
This is a problem for networks that use NAT (Network Address Translation) because local IP addresses are private, hidden behind routers. The solution that eventually worked was using a VPN called Hamachi https://secure.logmein.com/products/hamachi/download.aspx on both the remote and base computers. Hamachi servers are setup on both computers and connected to each other. This allows the computers to ‘see’ each other as if they were on a local network.
Max and Osc
Max patches are run on both the base and remote computers. The Max patch on the base computer connects to the radio using the serial object and passes commands back and forth over the internet using udpsend and udpreceive (which use Osc).
The Max patch on the remote MacBook sends and receives commands from the base computer using updsend and udpreceive. With the Hamachi VPN, Osc works just like it does on a LAN (local area network).
Automatic reconfiguration of clients
The main advantage of this system is that when you move the remote MacBook to a new location – for example, a coffee shop with public Wifi – both the Mumble and Hamachi clients automatically reconfigure for the location. So you don’t need to know the actual IP address of your computer in the coffee shop. The reconfiguration usually happens within seconds after the Wifi connection is made.
Alternatives
If you are just working across a LAN, you don’t need a VPN. Osc will run on a local network using private IP’s.
For uni-directional Osc communication from remote to base, in a WAN (wide area network) you can use a static IP address for the target.
Skype is another (free) solution for transmitting VOIP audio. Set the base computer in auto-answer mode and call it from the remote computer. Skype will process the audio more than mumble, with noise gates and such. And the latency is higher. But its very easy to set up.
Development
The next step is to build a remote interface for the radio that uses Midi/Osc controllers, so for example you can turn a dial on the Midi controller to change frequency or filter settings on a base radio.
Replace the potentiometer in the “Arduino Serial Read” project with a photocell (LDR: Light dependent resistor) and a 10K pulldown resistor, wired as shown in the image above and explained here: https://learn.adafruit.com/photocells/using-a-photocell (from Adadfruit)
The “Analog” lead represents the center terminal of a potentiometer and connects to A0.
The Arduino sketch is the example sketch: Analog | analogInOutSerial
First, think of a way to get the same results without writing an external. For example, borrow other code, use javascript, gen, Processing, or MSPaint.
Apparently that didn’t work out. Well I can only get you so far.
The .mxo file will be under the Products folder. <Ctrl> click to show in finder
Copy the .mxo file into the same folder as your Max patch
What Max patch? This one:
The window on the left is inverted because its getting that way in the object we just hacked.
That’s all
I didn’t really explain anything. Sometimes going through the motions is a start. If I had to do this for a living I would find the example that is most like a desired result and hack away.
