[Orion] Question about noise floor

[Bill Tippett]

         I got this from Lee KC9CDT and am forwarding it
to the reflector for general info (less the .pdf attachment
which the reflector cannot handle.  This attachments is
provided with all firmware revisions 1.363 and later).

                                 73,  Bill  W4ZV

At 10:06 PM 11/10/03, you wrote:
>Bill,
>Thanks for the reply.
*******************************************************************
>If this is the csae... THE ORION IS BROKE!
>You should not have to do that to use the XCVR without the NR on.
*******************************************************************

>Do you agree?

         I don't think so but it's hard to say without having the
radio in front of me.  Try the following:

1.  Select the unused antenna position as you did before.
2.  Press AGC - Slow, and then Menu - RX, and note the AGC
setting.  Now adjust it full CCW to the minimum (00.37 uV).
3.  Now slowly adjust Threshold from minimum upwards while listening.

In the 2-3 uV range, you should begin hearubg the noise floor drop off
and continue dropping as you raise Threshold.  This is normal, and
is why TT's default settings for Threshold are now 3.03 uV if you
have the firmware rev 1.363 or later.  See the attached .pdf file
for info on AGC and also carefully read this webpage:

http://www.tentec.com/565optimize.htm

Having had my Orion since August, I would say the above is
slightly wrong in a few cases, but carefully reading it will give
you a good idea of where to start with AGC settings.  I normally
never set mine below about 3 uV and it is often much higher in
extreme QRN like you have on 160 meters.

Also read ON4UN's comments in Paragraph 5 here:

http://dayton.akorn.net/pipermail/topband/2003-October/017574.html

         I'll bet you a beer that your AGC setting noted in Step 2
above was near the minimum, which was causing the Digital
AGC to boost the noise.

                                         73,  Bill  W4ZV