Sharp R-390S Bedienungsanleitung PDF herunterladen (Seite 9)

Panadaptors for the R390 page 9

limitation in the SB-620 with the 455 kHz IF, but I forget what it is at this moment. I

think it is 1 mHz. Still useful in crowded situations, beacon DXing, and looking for

clandestines that jump around to avoid jamming, etc.

---------------------------------------------------------

------------------------------------------------------------------------------------------------------

From: "Kenneth G. Gordon" <[email protected]>

Date: Thu, 12 Jun 2003 23:04:28 -0700

Subject: Re: [R-390] Coil forms and more...SB-620, etc...

You fellows might want to take a look at Kees Talen's web site. He has info on winding

coils for the SB-620 for the other frequencies and service data.

http://www.qsl.net/k5bcq/

----------------------------------------------------------------------------------------------------------

Date: Fri, 13 Jun 2003 08:01:18 -0700 (PDT)

Subject: [R-390] SSB on the 390 series

A few have asked about the item I sent a few years ago, relating to reasonable SSB on a

unit not intended for SSB. They wanted the method again.

We have so many experts on this list...I hesitate to write up the method taught me long

ago. I got it straight from Cpl. Stone . ... when I was young and viable...(?) But you don't

have to be highly sentient to do this..The ability to listen is the most important

requirement.. First of all, while pitch discrimination ranges from perfect pitch, to tone

deaf, my understanding is that all can generally detect a very small change in pitch.As a

result, the best, (or lowest, in case of the 390), point for the osc, (usually called

BFO..)can be determined easily. The change detected by most people is 4 to 5 cents, or 4

to 5 / 100 of a half step in music pitch, a very small ammount indeed. It is, by the way,

this ability that allows highly experienced persons to align w/ amazing sucess, with only

the ear. (That is, "manually", as is often said). In mil. practice, I saw alignment done to

near perfection with this method.. On the above, I refer you to an enormous amount that

is available just using the term "sound"..on the internet...Add "music", or "physics" and

you could not read it in less than a lifetime..I will not continue on acoustics, but suggest

you might want to read, if you never have..(By the way, my minor was Acoustics. I once

thought I was bright enough to be an engineer..) It is important to remember that you will

always hear a harmonic content in any sound, and you have to listen carefully. It is of

interest that the result for all radio SSB transmissions, is sometimes as good as the best

converter..It will depend upon being very careful to find the correct settings, and on your

filters.

The Method for the 390 series Is...:

1 Remove ant. and go to a very quiet point (rel. to the internal noise). Remove BFO knob,

and with BFO switch on, tune BFO to find point where the pitch, or the harmonic

1 2 3 4 5 6 7 8 9 10 11 12

Keine Kommentare

Sharp R-390S Bedienungsanleitung Seite 9