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IC-746 FAQ
While we can't yet prove the above assertion, data compiled by WA0KWK from voluntary
usage reports (brightness level, operation time, problems and repair, etc...) would seem to
support the theory. The raw data is at:
http://groups.yahoo.com/group/IC746/database?method=reportRows&tbl=2
Of course if your 746 is still under warranty, you may want to consider going that route.
Either way, you can contact Icom for the parts you need.
Alternate Prevention and Possible Field Repair
AD6ZU (Roy) reports that his 746 exhibited this problem when he shut the power supply off
while the 746 was left "on", then turned the power supply back on a while later. Once on,
changing the brightness setting would restore the LCD. Furthermore, when he powers down
the 746 before shutting off the main power supply, he has no problem.
6.8
Is there some way to get the Icom-746 to generate DTMF tones?
No. The IC-746 will not generate DTMF tones.
However, you have some options for generating DTMF tones yourself.
The good news is that Icom's compatibility table shows that the HM-14 DTMF hand
microphone will work with the IC-746. It even comes with a handy switch to enable/disable
the UP/DN buttons (if only the buttons would work). Remember, you have to press the PTT
switch to use the DTMF pad.
The bad news is that the HM-14 is a discontinued item, so availability is limited. Also, as
K9HFX discovered, there are apparently two versions of the HM-14. The version without
the scan button enable/disable switch did not work for him. More information is needed.
While not listed on Icom's compatibility charts as such, VE2MHF reports that the HM-56A
also works, even the scan buttons and 14 DTMF memories. However, beware, as VE4HAY
reports that the DTMF pad on the HM-56 will also work with the IC-746, but it's scan
buttons will not. We have to be careful of the 'exact' model numbers.
Icom confirms that the HM-118T will work with a suitable wired adapter. There is also
speculation (but no confirmation) that an HM-95 microphone might also work with a suitably
wired adapter. If you succeed with such an experiment, please let us know.
KC2CJW has successfully adapted an Alinco EMS-11 microphone for use on the IC-746.
You'll need two cable-mount 8-pin microphone connectors (one female, one male), a couple
of inches (maybe a foot) of decent multi-conductor cable, a 470 ohm resistor, and some
soldering skills. Paul can provide pin-outs upon request.
Another option is a portable tone dialer, such as one that you could get at any Radio Shack.
Just send the tone sequence right through the microphone. Not all such devices give access
to the 'A' - 'D' tones, but those tones don't get used much anyway.
Some have suggested wiring a DTMF pad into a microphone cable, much like what you
would do for a TNC. However, as yet, nobody has shared any success stories. Far Circuits
at:
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2003-02-08