HFLINK News About ALE
HF Digi Messaging
Emergency Comm
Get Started ALE
ALE Software
HFLINK is the international resource for ALE Automatic Link Establishment High Frequency Communications
HF Digital Messaging - Emergency / Disaster Relief - Interoperative Communications - Ham Radio

HFLINK

ALE HF Communications
High Frequency Network
HFLINK Group




ALE HF Communications
Global HF Network
HFLINK Group Forum
Propagation Now
Ham Radio ALE
ALE On Air Now
ALE Frequencies Join HFLINK Free Read HFLINK Forum

Hardware Recommended for Use With PCALE
Member Store
PCALE functions as an ALE controller with almost any popular amateur or commercial HF radio.

How PCALE Controls the Transceiver
For rapid channel scanning, PCALE uses the computer- to- radio CAT interface to control the transceiver frequency.
Most of the usual computer - radio interface boxes that are commonly used for ham radio digital modes or transceiver computer control work fine with PCALE. Generally speaking, if you are already set up with ham radio digital mode and CAT control, then it is likely you can get basic ALE running with PCALE using your present system*.

PCALE sends PTT control via the RS-232 serial port, normally using the RTS (or DTR) pins of DB9 or DB25 connector of the computer (or a USB-to-Serial adapter).  The RTS line goes high when transmitting. Hardware PTT is recommended.

Homebrew Interface
Most newer radios have USB soundcard and don't require any interface. But, for older radios, yo may need hardware control. It is possible to construct your own interface. Schematics for homebrew interfaces are on the HFLINK Interface page here, and some of these provide speaker muting that un-mutes the station external speaker whenever another station calls you. This feature can also be adapted to ham radio interface boxes that have a "CW keying" feature, by the addition of a relay in the speaker line.
Click to zoom on interfaces:

Simple Hardware Interface for ALE

Selecting a Transceiver for ALE service with PCALE

While almost any HF transceiver is suitable for ALE work, some transceivers are better suited to continuous 24/7/365 ALE service than others.

The following recommended transceivers have internal receiver bandpass switching circuitry that is optimum for fast Quiet Relay Scanning and Sounding with PCALE.
(These radios use diode bandpass switching for receive scanning, and only use relays when transmitting)
ICOM
The following Icom radios are compatible with PCALE Quiet Relay Scanning, and are recommended: IC746, IC746PRO, IC7400, IC756PRO (Milspec 1030E-DSP), IC756PRO2, IC756PRO3, IC765, IC775, IC781, IC7800, and possibly IC-7300. They have diode switched filters, and are capable of up to 2 ch/sec scan rate. Newer models running with CAT at 9600 baud can scan up to 5 channels/second. The IC756pro series and more recent models can run at 19,200 baud and are capable of 10 channels/second scan rate. (Note: the IC7800 has diode switched filters but has mechanical relays in the mixer, so some acoustic noise will be heard.)

Quiet Relay Scan Mods (hardware modifications) are documented for several popular Icom radios. These may provide the most cost effective solution for a scanning ALE radio system.
Icom IC-718 Quiet Relay Scan Mod
Icom IC-7200 Quiet Relay Scan Mod
Icom IC-M710 Quiet Relay Scan Mod

KENWOOD
The following Kenwood radios are compatible with PCALE Quiet Relay Scanning, and are recommended: All Kenwood models after TS-440 (but excluding the TS-440). They have diode switched filters. The oldest models are capable of up to 2 channels/second scan rate. The more recent models work at CAT rates of 9600 baud for up to 5 channels/second, and newest models work at 19,200 baud at 10 channels/second scan rate.
YAESU
The following Yaesu radios are compatible with PCALE Quiet Relay Scanning, and are recommended: FT-920, FT-990. They have diode switched filters, and are capable of up to 2 ch/sec scan rate.
(It is also possible to modify the FT-890 with a special QS/S mod that enables solid-state scanning; you can ask about this mod on the HFLINK forum)
HARRIS
The following Harris radios are compatible with PCALE Quiet Relay Scanning, and are recommended: Harris RF-350 family: RF-350, RF-350K, RT-1446 URC, AN/URC-119, AN/URC-121(V) The quiet relay scanning is handled by the BYPASS command, supporting up to 2 ch/sec scan rate.
OTHER RADIOS
Most other radios that are not on the above lists will still function fine with PCALE. Radios that don't have diode switched filters use mechanical relays. Even though they are not Quiet Relay Scanning compatible, they will scan in Simplex on a single VFO, rather than using the Split VFO method. The bandpass relays will be clicking every few seconds during scanning. This isn't technical a problem (unless the clicking in the background bothers you). Some radios have relays that are barely audible, while others are acoustically noticeable. By limiting the number of channels in the scan group to less than 11 channels, it is possible to be compatible at a scan rate of 1 channel/second. Even though Quiet Relay Scanning transceivers are recommended for long term continuous 24/7/365 ALE use, many operators are currently using normal relay switched transceivers that have been running perfectly in ALE service for years. All operators are encouraged to use whatever transceiver they have, to get on the air with ALE.




CONTENTS

Soundcards

Homebrew Interface

Selecting a Transceiver for Use with PCALE

Quiet Relay Scan

Icom

Kenwood

Yaesu

Harris

Other Radios

Scanning of Radios Without CAT


HFLINK Home
HFLINK News
More HFLINK News
Join HFLINK Group - Free
Member Store
Automatic Link Establishment
Ham Radio ALE Operating
Ham Radio ALE HF Network 
ALE Channel Frequencies
ALE Software & Download
ALE Transceiver Info
ALE Antenna Info
ALE Comm Standards
ALE Technical Info
Ham Radio Bandplans
HF Propagation Now
ALE Geo Position Report
ALE Interoperable HF Comm













Soundcards
It is best to use a good internal PC soundcard or the laptop built-in audio. Cheap USB soundcard dongles or inexpensive USB radio interface devices that have built-in soundcards may be OK for some ham radio digital modes, but they are generally not capable of decoding ALE with PCALE because they do not have real 48kHz sampling. It is also necessary for the soundcard to have an accurate clock, within 15Hz when the audio is measured at 2500Hz. Off-frequency soundcards often show up as a problem  decoding the ALE signal. Be sure to calibrate your radio and your soundcard before setting up ALE.




How Quiet Relay Scanning Works
PCALE uses the SPLIT VFO feature of the transceiver, and commands the radio to set the TRANSMIT VFO on a fixed frequency. Then PCALE command the radio to scan only the RECEIVE VFO. Certain models of transceivers are compatible with Quiet Relay Scanning. Other transceivers that don't have this feature will work OK for ALE, but PCALE scans them in single VFO mode, instead of Split VFO.

Quiet Relay Scan Functional Block Diagram

Typical Relay Switched Filters:

Typical Relay Filters

Typical Diode Switched Filters:
Typical Diode Switched Filters


Scanning of Radios Without CAT
PCALE can also control radios that do not have CAT, but have channel memory. The special PCALE software for this "hardware pulse scanning" is available by inquiring on the HFLINK forum. Select Hardware Pulse from the radio type menu. Connect the RS-232 port TXD line via a transistor interface to the radio's "Up Channel" mic button line.
 

























Back to Top
About HFLINK
HFLINK HOME
Join HFLINK - Free






END OF PAGE

©2017 HFLINK. All Rights Reserved.

HFLINK, HF-LINK, HF LINK, and the HFLINK Logo are trademarks of HFLINK division of HFpack Inc. Any external hyperlinks must only be to the main page of the HFLINK.COM website http://hflink.com . Capture of the HFLINK website or any part of it within the frame of another website is not permitted. HFLINK group forum is a private group. Public archiving, forwarding, or open display on the internet of HFLINK group forum or messages is forbidden. All text and images on the HFLINK website are property or copyright HFpack Inc, or when used by permission, are copyright by their respective owners, with all rights reserved.
HFN and High Frequency Network are service marks and trademarks of HFpack, Inc. No part of the HFLINK website or HFLINK Group Forum may be used or copied without written permission of HFLINK. HFLINK is a division of HFpack, Inc.
























































































































HFLINK is the international resource for ALE Automatic Link Establishment High Frequency Communications, HF Digital Messaging, Emergency / Disaster Relief, Interoperative HF Communications, HF Network, Ham Radio.