N6GKJ Allstar Node Notes Page

This page is dedicated to my experiments with the Allstar Link VOIP Project. I have setup several Allstar Servers now with complete success
I have several computer servers, we call them nodes, they are VOIP computer servers interfaced to Amatuer Radio's. The intention is to use the
"NODES" to allow remote operational reciever for the WB6ASU Repeater on 147.090 Mhz. I have already built and tested one node that is ready for install in Galt, Ca. I have secured rack space at the Old City Hall tower site that still has the tower in place. I will be placing one in Lodi, one in Acampo and one in Tracy. Future plans will include 3 nodes in Stockton as well.

UPDATE: 04/15/2013
HP5745T Thin Client - I now have NODE 27946 running on RAM DRIVE! I have loaded the files needed to run a nearly full ACID install into the 2GB internal flash. There are many steps to this proceedure none of which are complicated.
For information click here to find out what I did.

URI and Sound Fob's

I have played with URI's and Sound FOB's, the URi aways sounds better and is much more user friendly than using the Sound FOB's. The URI is a straight forward setup, alignment and deployment.

The Sound FOB on the other hand is another story, first you need to find one that has a real CM108A or CM119 Chip inside. These units can be found on EBAY and other from other Vendors fairly cheap. I bought a few on EBAY before I found one with a CM108A chip, however......
This unit was NOT what I expected, the chip is bonded to the board without a case and cemented with ceramic epoxy, this does not provide access to the GPIO output pin needed for PTT control.

The work around.....
Here is my process for getting around the GPIO issue. The units I purchased do have the GPIO inputs tied to momentary switches and I suppose those could be tapped for COS and CTCSS detect.

During my many testing sessions I noticed the FOB had a high frequency noise on the mic input that is used to tie the reciever audio to. In normal operation, there is a pad consisting of two resistors in a series parallel arrangment, audio passes through a 470K resistor in series with the mic input the cold side of the series resistor is tied to ground through a 68k resistor. In the usbradio.conf file the line for rxboost is set to rxboost=0 this adds and addtional 20db pad. What I found was poor quality parts used in the input and output connectors. I procceded to "clip" them out and solder my cables directly.... very bad idea, these boards tear up very easy, the pc traces lifted off the board.
I found my noise component in the jack itself, I could plug and unplug the connector and hear and increase in noise, I soldered the leads directly to the jack istself and the noise reduced to almost nothing. I believe that noise in inherant in the device itself and might not be there if I select a device from a different manufacture.

I cant cut the jacks out, so I simply passed my audio cables throught the center of the jacks and solder the shields to ground and the center leads directly to the jack pins. This arrangement works well.