[TenTec] guide to adjusting Orion receiver; filters and performance

[Jim Reid]

KH7M wrote:

> > Meter drops to around -130 dBm on the dummy
> > load, from -119 or so on the 40 meter band.
> > This using 3.4 kHz BW on on the 340!
> 
Sinisa responded:
 
> Which translates to -184 dbW/Hz, a fascinating
> figure for 40 meters, good even for 10 meters.
> What time of (UTC) day?

0045 UTC,  or 2:45 pm Hawaii Standard Time

> For a "remote" location in your area ICEPAC suggests
> from -171 to -155 dBW on 40 meters, and -186 dBW on 10 meters.
> 
> Are you sure that you don't have too much loss
> on 40 meters?  :-)   What was it, a doublet?

Well,  I am about 2 miles inland from the South facing
coast of Kauai,  and at an altitude of some 500 feet ASL.
Antennas have a clear view of the ocean over nearly
200 degrees of Azimuth,  centered nearly directly South.

Yes,  the 40 meter antenna is an 80 meter doublet,
center fed using 600 ohm (4 inch spaced) open wire
line.  The antenna length is about 125 feet;  the open
wire feeder is about another 100 feet.  The tuner is
an "ancient" E F Johnson kW Matchbox,  balanced
tuner.  The tuner is from the 1950's,  hi.  It cost all
of $124.50 when brand new!  Has very large C's
and a big split coil inductor using a center link
primary coil.  I use three turns of the link coil on
40 meters,  resonating the primary circuit with a
series capacitor added to the input circuit.

73,  Jim  KH7M
On the Garden Island of Kauai