WB4FAY.com -- Birmingham, Alabama

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Last updated: 01/25/11  Copyright (c) 2003-2011

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WB4FAY-L Configuration

(Node Number 7148)


Link configuration

The WB4FAY-L node consists of an internet connected computer, a 2 meter transceiver (on 147.280 MHz), a 70cm receiver for control operator access, and an interface board which is used to interconnect the computer and the two radios.   The interface was purchased as a kit from WB2REM.  On June 21, 2002 the PIC in the interface was upgraded to WB4REM's version 2.0 chip.  The primary reason for the upgrade was due to the addition of a configurable time-out timer which had been added to the code in the PIC.  Pictures and further information on the interface are shown below.

The PC is connected to the internet via a DSL link and is connected to the interface board with 3 cables (audio in and out, and a serial cable to COM1 or COM2 for PTT control).  The software is the EchoLink software (http://www.synergenics.com).  New versions with more features are coming on a regular basis so watch for increased functionality in the future.

The main radio is the 2 meter transceiver which is used for communication on 147.280(+) with the W4TPA repeater in Birmingham.  There is no physical connection with the repeater.  All linking is done via RF on the main repeater frequency.

The auxiliary radio is the 70cm receiver.  This is used exclusively for remote shutdown of the node should a control operator determine that it is necessary.


Pictures and information of the interface used at WB4FAY-L

This is a picture of the interface board after assembly but before it was mounted in a metal enclosure.  Note that the mini-phone plugs and the LED's have not been mounted on the board because they will be mounted on the outside of the enclosure instead of directly on the board.

The board was assembled easily in about an hour and operated properly the first time power was applied.



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This is the board after it has been mounted in the enclosure and wired to all of the switches, LED indicators and the external connectors.   The board is mounted via the DB-9 connector.   All of the interface connectors are on the rear of the enclosure to keep the cabling neat.

Not visible in the photo is a 1:1 audio transformer under the board that in the audio output to the transceiver microphone input.




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This is the front of the fully assembled interface.  The two LED's were lifted from the WB2REM board and mounted here to indicate 'power' (red) and 'activity' (green).

Switches were added to control (right to left):

  1. Power
  2. Push to talk disable
  3. Audio source (Main rcvr or microphone)
  4. Main Receiver Audio (to link or speaker)
  5. Aux Receiver Audio (to link or speaker)
  6. Audio output from computer (to link or speaker
  7. Program Mode (ON: open D4 LED, power to JP1)

Note that the switches are all mounted so the up position is the normal operating position.

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This photo is the rear of the enclosure where all the connections are made for the iLink.  Connections (left to right) are:

  1. Main transceiver (note the use of a 5-pin female DIN connector).  This connection is wired to match that of a TAPR-2 TNC for easy of radio interface cabling.

  2. Aux Receiver audio input. (2 conductor phone jack)

  3. Microphone (3 conductor phone jack)

  4. Speakers (3 conductor phone jack)

  5. Computer Audio In (3 conductor phone jack)

  6. Computer Audio Out (3 conductor phone jack)

  7. Program Voltage - 15-20 VDC (Coaxial 5.5mm/2.1mm)

  8. Main Power - 12 VDC (Coaxial 5.5mm/2.1mm)

  9. Serial interface to computer COM1 or COM2 (DB-9)

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