I’m running a project together with YO3KSR ham radio club in Bucharest. It aims at running app_rpt on an small WL500 router in order to make radio-VoIP-radio network. In the picture below one could see a router connected with a GM300 rig and the power supply for the rig. This article is just a short list of information on how to replicate the solution.
It’s actually a WL500 Deluxe board together with a GPRS board (not used in this project) in a different box. It’s sold as Topex BYTTON GPRS.
Three USB connections are used:
– USB sound card – I’m using CM108 based card as of now but you may try a different card because I use chan_alsaradio driver.
– Mass storage flash card
– USB to RS232 converter for signaling (PTT and COR) – I’m not using the GPIO pins on the CM108 card because the requirement was to be able to use any kind of the USB sound cards that may not have GPIO pins.
The order of physical USB ports is important, it should be like in the picture. Otherwise you need to adjust configuration files.
Here is the connection board schematics for the PTT and COR:
The application is made to run on OpenWRT 10.03. You need to install it before attempting to install app_rpt.
Since the board has so less flash memory (4MB), the USB flash drive is used to keep the new root filesystem. In order to boot from flash drive you need to replace /sbin/init on your onboard flash filesystem with the following script: init. The script will switch from on-board flash root to the root mounted from USB flash drive.
Download the new root filesystem: from here
You need to make two partitions on the flash drive:
1. swap (~100M)
2. ext3 (the rest) – copy the content of the archive on this partition
Adjusting various bits:
Accessing the system after mounting USB root filesystem(user root, password admin): ssh firstname.lastname@example.org
Changing the default IP address (192.168.1.3): use your web browser and access the LuCI interface: http://192.168.1.3
Adjusting audio levels: after you login with ssh use “alsamixer -V all”
Changing default node number (27237) and relation between node number and IP address: modify node number in /etc/asterisk/rpt.conf, and node number and IP in /usr/lib/asterisk/rpt_extnodes .
Inverting PTT signal: set invertptt=1 in /etc/asterisk/alsaradio.conf
Inverting COR signal: set carrierfrom=serialdsr or serialdsrinvert in /etc/asterisk/alsaradio.conf
Using the system:
Suppose you have two systems, first one with node number 27111 and the second with node number 27222. In order to dial from one node (27111) to the other:
*327222 from node 27111.
To disconnect: *127222.
You could configure and use any options app_rpt has.
Overclocking the router:
If the sound is chopped you may try to overclock the router . DO IT AT YOUR OWN RISKS!
For WL500 Deluxe:
nvram set clkfreq=264,132
I hope this is enough for someone to get started.