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RE: [linrad] IC706MKIIG

Hi Leif,

Some radios will momentarily put out full power on keydown when
the power is turned down. In that case your 10 amp supply may
breifly shut down in response to the peak current demand (some 20 amps). I have not
tested the 706 for this problem, but it is common. On 144 with the lower
power final, your 10 amp supply will never be exceeded so it would operate
properly there. A scope on your power supply lead would tell you if this is the problem
or not. You could also power the radio from an idling vehicles power source
and repeat the key click test.

73, Jim Shaffer, WB9UWA.

On 9 Dec 2003 at 22:55, Leif Åsbrink wrote:

> Hi Jim,
> > The 706 series is very picky about low power supply voltage.
> > I had to run #4 welding wire from my battery so I could run mobil
> > with the engine off. Somewhere near +12 volts and the frequency
> > becomes unstable. If your power source spikes momentarily below 12
> > volts, it is very likely to cause a problem. This may or may not
> > relate to your problem, but is something to check. Some shortcuts
> > were taken in the 706 design, especially the noise blanker.
> OK. I do not think I have any problem here. I have a good 10A
> supply. I can not run at full power, but the problems are not
> changing when I change the output power. On 144 MHz the keying is
> perfect at all power levels.
> It seems the ALC (=driver stage gain) is not something the user is
> supposed to adjust. I have also received comments saying that this
> radio is known to be problematic on CW.
> When set for full break-in it causes terrible keying clicks. This mode
> should never be used in IC706MKIIG.
> 73
> Leif