I don't have an 87A, but do have an Alpha 89 and two 99s, plus two
IC-781s. Here are some comments on these pieces of equipment.
I never use the ALC on the Alphas.
When using the 781 on CW, be sure to turn off the 781 compressor /
processor.
It really puts a sharp edge on the leading edge of a "dit", when
observed on a digital storage scope.
One of my 781s has the ALC fix covered on W0CP's web site, and one does not.
Since I run very little ALC, the mod hardly matters, though I should get
around to fixing the second one.
A Tektronix 100 MHz scope is always monitoring the RF going to the
antenna switch. Can't imagine operating on SSB without it.
Assuming you are running the Alphas at legal power, if the LED output
goes over 1 kW on SSB you are flattopping.
I set the 781 drive control so the ALC meter reads up scale only a
little bit. More ALC than a little bit, you have overshoot.
The Alpha 89 when set to CW mode really messes up the CW keying
waveform, thus I run it in SSB mode even on CW.
Just a side note:
The overshoot on the 706MkIIG is terrible, and there appears to be no
way to adjust the knobs to fix it.
The 706 splatters badly if you hit the ALC any significant amount.
The stock mic gain setting and stock ALC level does not produce a clean
signal.
73, Rob, NC0B
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|