Got rejected by Orion list - dunno why - so posting here.
To present some DATA rather than believing what my ears were telling me , I
reloaded 1.372 and made audio out measurements and then reloaded 2.059 and
made the same measurements.
CAVEAT : Trying to decide how to set equal audio gain control levels for
both cases I decided to use the RS232 controls to set audio gain at 130
using command *UM130 . If there is a software issue with this , I am unaware
of it but there might be. (Max gain is *UM255 so I am at about half scale
and that is about where the "bar indicator" shows gain.)
Another caveat is that I always get an error message when I try to load
2.059 saying "Communications with radio has failed .......and the radio may
not function." I repeated this several times with master resets etc etc ad
nauseum and finally just let it run its course then ran a verify and it
says all is OK, and the radio seems normal as 2.059 goes. I have tried
rebooting with serial cable off , verified my Hyperterminal program for
RS232 commands is off and not talking - so far cannot stop that message .
Any GURU suggestions there are appreciated !
ANYHOW:
The below measurements are with Main RX with BW of 100 cycles and 2400
cycles both LCW.
7040 khz with 50 uv from an Elecraft oscillator to the external ant port.
Spot frequency 400 hz.SPOT level set at 50 in both cases.
RF Gain at 100 for all cases. AF Gain as above set by RS232 to *UM130
Voltages measured across a 5 ohm load on the
external speaker terminals with a FLUKE 179 RMS ac voltmeter.
1.372
BW 100 hz AF out is 303 mv , SPOT is 595 mv
2400 hz AF out is 365 mv , SPOT is 633 mv.
2.059
BW 100 hz AF out is 52 mv , SPOT is 740 mv
2400 hz AF out is 53 mv , SPOT is 762 mv.
To get AF output about the same as 1.372 I had to increase AF gain to *UM170
(gives about 350 mv)
303/52 MV is down about 15 db at about half audio gain.
365/53 about 17 db.
Relative spot level is up 740/595 or 1.9 db.
So in fact the spot level is not terribly higher , but the normal audio is
way lower .
I think this discrepancy also contributes to the CW monitor slurp artifacts
I hear in the headphones. Sounds fine on the internal speaker , but pretty
lousy on my SONY MDR V6 phones I have used for a year or so. (NOT external
RF in the phones _ its there even at 10 watts into a dummy load)
FWIW -- Hank K7HP
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