Hi everybody,
Some remarks to the relatively high audio noise (in my opionon)
- The rig is a new one with DC-connector (bought in Dec. 95, high serial nr.)
- The FT990 had been tested in the "Beam"-magazine (in Germany) and
they measured a noise floor at approx. -128 dBm which is not too low
(or too good) compared to ICOM 765 or equiv.
I heard equal opinions on the band also.
- What I mean is, if you short-cut the antenna input (no noise can come out of
the shack any longer) and turn the AF-gain at approx. 9 o'clock
the noice produced is simply too high (in my opinion)
It comes out of the IF-stages. (If you make it more insensitive by turning
the RF-gain to the right -> that's the way it's realized) and then the turn
the AF-gain to a higher loudness, you won't hear anything because the
audio amplifier is quite good. So it's not the AF-stages. (And it really has
nothing to do if I have a bad antenna connection (in that case), Hi,Hi)
So maybe there are ground loop problems (as Walt K8CV mentionend)
or bias currents, internal shield problems or whatever
- Anyway I like the rig very much and would be pleased to get an address of
YAESU where to put the questions because on calm bands it's really a pitty
73, Friedemann Heyer still DG9GM
EMAIL: friedemann.heyer@bnr.ca
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