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IC-746 FAQ
Physically stack the two transistors atop each other with the two emitters twisted
together. This helps to keep the volume down.
A little heat shrink tubing may help here and there, but use it very sparingly; it adds
volume and a smart layout really doesn't require any.
Use a highlighter to trace out the connections you've made. It's easy to get mixed up as
to which connection you've made and which ones you haven't.
Be sure to strain relief the cable in the shell. An inadvertent tug on the cable can pull a
connection loose or cause a short circuit (nothing will "burn out", you'll just lose the
communications and start pulling your hair out).
When you complete the interface, if it doesn't work, recheck your connections and follow
the schematic again. The design REALLY DOES WORK. Most likely, there was a
mistake in the soldering.
You can also purchase many renditions of these hardware interfaces from a variety of
sources:
Universal RS232 Serial Interface for Icom/Yaesu
http://www.butel.nl/icomr2/icom11.html
K1NU ICOM Computer Control Interface
http://home.att.net/~k1nu/k1nu/Products/
RTS-01 Computer Interface cable for Icom HF Radios
http://rtsars.com/othercables_template.cfm
http://www.sarrio.com/sarrio/w1gee.html
5.4
Do I need a special cable to connect a CT-17 to an IC-746?
No - the cable is a simple 2 wire cable with a 1/8" miniature phone jack on each end. When
homebrewing, some folks don't even bother to shield the cable and just use a twisted pair.
5.5
What is the control protocol for the IC-746?
5.6
What is CI-V?
CI-V is the control protocol used by ICOM for remote PC control of their equipment.
This feature was originally used to enable a separate transmitter and receiver to act as a
transceiver when interconnected via the CI-V bus (the receiver acts as a "slave" to the
transmitter's QSY and mode-change reports) and for external amplifier control. It was only
natural to adapt it to computer control.
The basics of the protocol are documented in the IC-746 Instruction Manual on pages 74-75.
However, most people will prefer the documentation available from DF4OR's WWW site at:
http://www.plicht.de/ekki/civ/
or the documentation that comes shipped with W2ENY's control cables:
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2003-02-08