I usually find a spot on the band where there is no signal, no QRM or
splatter and with the antenna of choice. Turn the RF Gain up to the point
you see the noise flicker on the S meter. Note that level say S-6. I
normally use th SLW AGC as it makes the S meter a bit easier to read peaks.
Then I usually switch the radio to my dummy load and then adjust the RF Gain
such that the S meter indicates about 1 S unit lower than the previous noted
level or about S-5. Then back to the antenna. To me that optomizes the
gain for the antenna and noise.
With a bit of practice one can set the RF Gain just looking at the S meter
values and backing the RF Gain down as one gets a "feel" for what is taking
place. All the other steps are "just to make it easy" and repetitive.
Just remember, with Tentec radios the S meter always references S-9 as being
equal to ~50uV regardless of RF Gain values. Same is true with the ATTN
function engaged at some value or the Preamp engaged.
73
Bob, K4TAX
----- Original Message -----
From: "Kim Elmore" <cw_de_n5op@sbcglobal.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, April 23, 2012 10:24 PM
Subject: Re: [TenTec] 566 Orion II Firmware Version
V3.029 ---SpectrumDisplay &Tuning...
>I tried this with my OII, think that I must have missed something. I
> simply never see the S-meter drop and then rise as I decrease RF
> gain. Of course, it will drop if I turn off the preamp, but not as I
> change the RF gain setting using the multi knob. What I see is that
> the minimum S-meter reading rises as RF gain is reduced (as if the
> AGC voltage is being increased which is, in some sense, what's
> happening). At some point the minimum S-meter reading is above the
> maximum deflection due to static crashes. Then, any signals stronger
> than the static crashes will lead to an upward deflection. Am I
> missing something subtle? Does anyone else see the S-meter drop then
> rise as the RF gain is decreased?
>
> I set my SAF by ear as per the TT instructions, decreasing RF gain
> until I hear only a little ringing. Even though I am almost
> exclusively CW, I tried it a couple of times on SSB was surprised how
> much it helped on weak signals.
>
> 73,
>
> Kim N5OP
>
> At 02:38 PM 4/23/2012, you wrote:
>>A visual clue for setting RF Gain is the S-meter. While listening to
>>just noise, as you decrease the RF-Gain, the S-meter noise level drops,
>>and continues to drop, until you reach a point where the S-meter
>>reverses and starts to climb - while the RF-Gain continues to be turned
>>down. Thus, there is a point where the S-meter changes direction while
>>the RF-Gain is still being turned down. (Sorry... I find this
>>difficult to say in words...) The point where the S-meter reverses is
>>the sweet spot (although I find it is really just above that point...)
>>
>>Play with it and you will SEE what I mean. I think you will find the
>>S-meter reverses just at or just below the point where you can HEAR it
>>change over.
>>
>>I have an Omni VII and this works on it -- I spent time on my friend's
>>Orion II and it seemed to work exactly the same way, albeit at different
>>points on the dial. ...snip...
>
> _______________________________________________
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> TenTec@contesting.com
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>
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