Icom IC-746, Часто задаваемые вопросы

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IC-746 FAQ
6 Problems and Clarifications
6.1 What's that funny rattling noise I hear when I first power on?
Often, it’s the internal antenna tuning unit. The relays make audible clicking/rattling sounds.
6.2 What's that "click" I hear as I tune across certain frequencies?
The clicking noise you hear is very likely from the relays for the rig's preselector (the service
manual calls them RF filters). At each boundary point, the rig switches in a different RF
filter. There are several:
0 - 1.6 Mhz low pass
1.6 - 2 Mhz band pass
2 - 4 Mhz band pass
4 - 8 Mhz band pass
8 - 11 Mhz band pass
11 - 15 Mhz band pass
15 - 22 Mhz band pass
22 - 30 Mhz band pass
30 - 50 Mhz band pass
50 - 54 Mhz band pass
54 - 60 Mhz band pass
108-174 Mhz band pass
Some mistakenly call this the antenna tuner (there is even some component overlap),
however, the preselector and tuner serve different purposes and are each switched in and out
accordingly.
6.3 Why doesn't the ALC meter work while adjusting the "mic gain"?
Despite what the manual says, the ALC meter only works for SSB. It does not work for FM,
CW, or RTTY. Nobody knows what (if anything) the ALC meter means on these other
modes.
6.4 Why can't I set numbers into memory names, CW keyer, etc...?
Use the keypad to enter numbers. The dial only does letters and punctuation.
Page 66 of 113
2003-02-08