On Mon, 31 Jan 2005 19:49:49 -0800, "Guy Atkins"
wrote:

Jim,

I take it you are using the sub-receiver of the Orion for SWLing, as the
main receiver covers just the ham bands and MARS frequency extensions +/-
10 kHz.

Yes

The sub-receiver has poorer SSB sensitivity than the main receiver (.35 uV
versus .18 uV) and poorer third-order intercept point (+5 dB versus +25dB at
20 kHz spacing). Have you found this a drawback for DXing, or is your main
receive-only use of the Orion for general SWLing (not DXing)? I'm interested
in your further comments on this.

I have not noticed much of a difference in sensitivity between the two
receivers. I was quite surprised by the selectivity of the
sub-receiver. I just happened to have it on medium wave one day and
was very impressed on how well I could just turn off adjacent stations
by narrowing the bandwidth. See below...

Also, I note that both of the Orion's receivers offer just two bandwidths
for AM mode. Is this a drawback, or do you like to tune an AM signal in SSB
("ECSS"), taking advantage of the many DSP filter choices in SSB?

The manual shows only two bandwidths but the AM bandwidth is
continuously adjustable from 6kHz to 100Hz.

I know the Orion is top-notch for ham band use, and its selectable roofing
filters for the ham bands help out immensely in this regard. For tuning the
SWBC bands, though, the sub-receiver of the Orion appears to be a step down
in performance (but maybe I'm missing something in the specs... :^)

I don't have any nearby radio stations and I don't have any
measurement equipment available but I would say the two receivers are
very similar. Even when using the main receiver the digital filters
works so well I normally leave the roofing filter in the wide position
for most amateur work. I am sure there would be some conditions where
there would be some benefit to the narrow roofing filter - contesting,
CW, etc.

I really did not intend to use the sub-receiver that much but I am
originally a SW DXer turned amateur and I am always drawn over to the
SW bands when I hit the AM button on this radio. I would have to say
the sub receiver audio and performance are awesome. Maybe they are
afraid to let on how good it is at Ten-Tec since the RX-340 sales
might suffer.

From a quietness standpoint, do you find the main & sub-receivers to be
equal, given equal bandwidths, AGC, etc.?

Both receivers are very quiet. I will have to set up and do a direct
comparison some time and let you know if I can detect a difference.

Jim



73,

Guy Atkins
Puyallup, WA USA



R.F. Collins wrote in message


.. .
On 30 Jan 2005 19:37:29 -0800, wrote:

I actually use the Ten Tec Orion more for SW listening than amateur
use. It has the best audio I have ever heard from a receiver. I use an
Icom 756 Pro II for contacts because of its ergonomics even though the
filters and audio are not as good as the Ten Tec. So there are many
things to consider when looking at a radio.

Oh yeah. If you like boat anchors you will be happy with the Ten-Tec
Orion. It is huge. It takes up more desk space than my linear amp.

Jim