Southeastern Asterisk Radio Networks

Asterisk app_rpt via USB

Sep 17

Posted by OPS in Asterisk, Asterisk RF, Communications, RF Gateways, Repeater Controllers | Comments off

A new low-cost way to interface Asterisk app_rpt to radio can now be used with a USB sound adapter. Some modifications are needed to bring out the PTT, block DC on the audio outputs, and attenuate the receive audio to match the microphone levels.
A new low-cost way to interface Asterisk app_rpt to radio can now be used with a USB sound adapter.
Some modifications are needed to bring out the PTT, block DC on the audio outputs, and attenuate the
receive audio to match the microphone levels.

From the qrvc.com web site the following features are mentioned:

chan_usb radio contains all of the interface code to interface app_rpt to a CM108 based USB sound fob.
In addition it contains DSP code to do CTCSS encoding and decoding, squelch, pre-emphasis and soft
limiting, de-emphasis, and audio level adjustments.

Basically, you only need to make 3 or 4 connections to your radio:

  • Discriminator audio, de-emphasized audio, or speaker audio.
  • Transmit audio (direct to modulator, or microphone)
  • PTT

A new doorway is quickly opening to continue the progression of Asterisk as the way to interconnectivity.

For more details about Asterisk app_rpt visit http://app-rpt.qrvc.com/

and information about Asterisk can be found at http://www.asterisk.org

ALE On-The-Air Week

Sep 12

Posted by OPS in Communications | No Comments

ALE On-The-Air Week
05-15 October AOTAW-2007
START:
0001 UTC 05 October 2007 Friday
END:
2359 UTC 15 October 2007 Monday

HFLINK sponsors this annual International Amateur Radio event.

All ham radio operators worldwide are invited to participate in 10 days of HF Automatic Link Establishment activity on the air. “AOTAW” is an open operating event for hams to explore ALE communications and equipment. The experience gained by operator participation in this readiness exercise is useful for HF Emergency/Disaster Relief communications.

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What are FXS & FXO?

Sep 5

Posted by OPS in Asterisk, Asterisk RF, Resources | No Comments

What are FXS & FXO?

FXS — Foreign Exchange Station

FXO — Foreign Exchange Office

An FXS device initiates and sends ringing voltage. FXS sends the voltage to an FXO device, which receives it.

Pitch Catch

The phone receiving the call is the last FXO device in the chain, and when it receives voltage from an FXS device, the phone will ring.

Connect the outside line to an FXO port on your Asterisk server to receive voltage from the outside lines.

Connect the phones to FXS ports on your Asterisk server. When the FXO module in your Asterisk Server receives the voltage, it will then generate voltage using the FXS module and send it to your analog phone.

CO PBX Phone

Hint: Remember the “to”… FXS = FX(to)Station and FXO = FX(to)Office.
       With “to” representing the direction taken by the signal.

PSKmail – Another Emergency Response Tool

Sep 4

Posted by OPS in Communications, Emergency Response | No Comments

PSKmail as described on http://pskmail.wikispaces.com/

PSKmail is a narrow band mail delivery system for use by amateur radio hams via short wave (HF) communication. It is only available for Linux (it is time to change to Linux anyway…). Unlike PACTOR, it does not use a special controller, you just need a computer with a sound card. PSKmail uses Fldigi in PSK125 mode.

PSKmail has a client/server architecture. Unlike Packet Radio (Q15X25) the PSKmail protocol only allows 1 connected client at the time. Bandwidth (3dB) is 129 Hz!!!

The PSKmail client is written in GTK2 perl. At this moment the applications is a Mailbox (port 24) allowing down/upload of mail from the internet, and downloading information from the web (ASCII text only), position update and station-to-station messaging via APRS(port26) and chat mode (TTY, port 87).

Version 0.4 has enhancements for emergency communications. This means that even if the internet backbone is down, you will still be able to send messages and files from client to client.

Pskmail now also works together with EVOLUTION and other Linux mail clients. You can then use the mail integrator you are used to (any mbox compatible system).

There’s a PSKLive (LiveCD) available to test with. The LiveCD allows one to operate the programs without accessing the hard drive on their computer.

As for Technicians … the 10m Band is the place we can use PSKmail on HF.

28.000 – 28.300 MHz: CW, RTTY/Data–
Maximum power 200 watts PEP

Be interesting to find out what kind of coverage is available.

Interview Audio Regarding PSKmail

Midian Electronics

Jun 25

Posted by OPS in Communications Equipment, Controllers | Comments off

Midian Electronics manufactures products for voice scrambling, tone signaling, paging and dialing, radiotelephone interconnects, remote control and more. Midian Electronics was founded in 1975 by Chuck Soulliard in Tucson, Arizona. Since its inception, Midian has been a leader in the tone signaling and voice security industries. Midian’s first products were tone signaling modules for land mobile radio. These included DTMF, pulse tone, two-tone, and five-tone encoders and decoders. In fact, Midian was the first to design and manufacture after-market DTMF and pulse tone decoders. In 1981, Midian entered into the voice security market by introducing the world’s first voice scrambler small enough to fit inside a portable two-way radio.

When you need to put together a low-cost repeater take a look at Midian Electronics RM-1 Repeater Maker a low cost simplex repeater maker. It offers 2 station ID’s or messages with programmable Morse ID tone frequency and transmit speed. Other features include Morse ID inhibit, hang time, time-out timer, and remote access/disable using DTMF signaling. Add the RM-1 to two radios and you have a repeater.

QRV Communications

Jun 25

Posted by OPS in Controllers, Repeater Controllers | Comments off

QRV Communications manufactures and sells cards which allow an Asterisk PBX system using the app_rpt application to be connected to FM land mobile two way radio repeaters and half duplex base station radios. We currently offer two types of radio interface cards. The PCI Quad Radio Interface, and the Analog Radio Interface.

The PCI Quad Radio Interface is the 4 port PCI radio interface card designed to work with the app_rpt application included in the open source Asterisk PBX. This card has 4 independent channels and can control a combination of 4 repeaters or 4 base stations concurrently and simultaneously. Each channel is has a CTCSS encoder/decoder, level adjustment pots, and an Audio In/Audio Out/COR/PTT interface suitable for interface to your radio system.

Arcom Repeater Controllers

Jun 25

Posted by OPS in Controllers | Comments off

Arcom Repeater Controllers

RC210 A full-featured controller, capable of independently controlling 3 independent repeaters, 2 full/half duplex links and frequency agile remote base operation (or any combination!) and many more features usually found only in arcom controllers costing hundreds, if not thousands, of dollars more.

RC810  Now you can control up to 8 repeaters, remote bases and link radios with only one controller. The base RC810 is supplied with 4 independently operating Radio Cards, expandable up to 8.

Micro Computer Concepts

Jun 25

Posted by OPS in Controllers, Repeaters | Comments off

Micro Computer Concepts is a manufacturer of radio repeaters, repeater controllers and repeater related accessories. MCC started making repeater controllers in 1988 and has supplied the Amateur Radio community with a variety of products. Read the rest of this entry »

Protocase, Inc.

Jun 25

Posted by OPS in Communications Equipment, Repeaters | Comments off

Protocase Inc. is a low volume custom electronic enclosure manufacturer. We manufacture rackmount, rack mount, rackmount enclosure, rack mount enclosure, custom rackmount, custom rack mount, rackmount chassis, rack mount chassis, u-shape enclosure, l-shape enclosure and other shapes of custom electronic enclosures.

TL-NET Wide Area 2-Way Radio Networking

Jun 24

Posted by OPS in Controllers, Repeaters | Comments off

Bridgecom TL-NET Wide Area Two-Way Radio Networking

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