[TenTec] ORION II the right rig for SSB ?

[Bob McGraw - K4TAX]

In "audio" terms, it is common to see average level being some 6 to 10 dB 
below peak power. Therefore, with 100 watts peak one would expect to see 20 
to 25 watts output average.  This is with little to no signal processing.

There is a difference in results when compression is used vs. peak limiting. 
Some ALC systems are peak limiting where others rely on compression.

Depending on radios and measuring systems, your mileage will vary.

73
Bob, K4TAX


----- Original Message ----- 
From: "Merle Bone" <merlebone at charter.net>
To: <tentec at contesting.com>
Sent: Wednesday, February 06, 2008 8:29 AM
Subject: Re: [TenTec] ORION II the right rig for SSB ?


> Mike (w2AJI) said:
> -------------------------------------------------------------------------------------------------------------------------
> " Even with the compressor set at 7, the O2 will produce about
> 20 to 25 watts average output at 70 watts PEP"
> "The audio in the O2, even with the compressor set at 7 is very good, and 
> very
> strong. "
> ------------------------------------------------------------------------------------------------------
>
>
> I think we all have certainly answered the original question about
> whether or not the Orion/Orion II is a good SSB radio - absolutely
> YES! And while not wanting to beat a "dead horse," I do think it
> is worth a little more data and a couple of comments. My previous post
> http://lists.contesting.com/archives//html/TenTec/2007-05/msg00478.html
>
> presented this data:
> ----------------------------------------------------------------------------------------
> Proc Setting     Audio Result   AVG  RF Power
>
> Off              Slight Expansion         ~8W
> 1 - 4     Close to no Compression   ~9-10W
> 5               ~5dB Compression       ~12W
> 6              5-10dB Compression     ~13W
> 7              ~10dB Compression      ~16W
> 8             10-15dB Compression    ~20W
> 9             15-20dB Compression    ~26W
>
> I tested the V1.373b5 code and got the following results:
> Proc Setting         Audio Result     AVG RF Power
>
> Off                   Slight Expansion               ~8W
> 1 - 4          Close to no Compression         ~9-10W
> 5                   ~5dB Compression              ~12W
> 6                  5-10dB Compression            ~14W
> 7                   ~10dB Compression            ~17W
> 8                  10-15dB Compression          ~24W
> 9                  15-20dB Compression          ~31W
>
> In all cases the peak power stayed very close to 39W - which
> is what I use to drive my Alpha 87A to 1500W peak output.
> ------------------------------------------------------------------------------
> Just a couple of comments about the data(See the reference link for
> explanation of the set setup and the test audio pattern). "7" is
> definitely not "the end" in terms of "usable compression" on the V1
> or V2 Orion code. An SP setting of "9" produces very good
> quality audio and generates nearly an additional 3dB of
> average output power - significant. Because the human voice,
> depending on the individual and on the words (Sounds) spoken,
> normally has a 15 to 20dB dynamic range, it's very hard to
> use more then that amount of compression without creating
> severe distortion.
>
> In both tests above, the "peak power out" was
> set to 39W (required to drive Alpha 87A to 1500W Peak).
> The V2, at SP= 9, resulted in an average power that was 1.7dB
> below the peak - you can't do much more then that (The V1
> code, SP=9 resulted in an average power that was about 1 dB
> below the peak power out). Both with very good quality audio.
>
> Finally, another radio amateur used a similar test setup
> to mine, with an Orion II, and reported virtually identical
> results as mine on the Yahoo 565 reflector.
> 73, Merle - W0EWM
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