The new audio clips comparing the two receivers is currently posted on my
site at www.n6ie.com. The clips are about 1 MB each, so if you have
dial-up, it could take some time.
BTW...my website has no ads, no music, no annoying 'dancing graphics', etc.!
Ron Castro
Chief Technical Officer
Results Radio, LLC
N6IE
www.N6IE.com
(Formerly N6AHA)
----- Original Message -----
From: "Ron Castro" <ronc@sonic.net>
To: "Ten Tec List" <tentec@contesting.com>
Sent: Wednesday, January 24, 2007 10:04 PM
Subject: [TenTec] O2 AM Distortion FIXED!
>I got a nice e-mail from Jack Burchfield at Ten Tec about the AM distortion
>problem. He listened to my recording and agreed that the Orion II didn't
>sound as good as it should, and explained that the dual-loop AGC system
>with the new adjustable hang time has to be slowed down to sound good in
>AM. He suggested using a hang of 3 to 4 seconds.
>
> I increased the hang time to 4 seconds and that cured the distortion! I
> didn't realize that the two AGC loops were so independent and I had been
> thinking that a slow decay time coupled with a hang time of more like .5
> seconds would eliminate AGC distortion from the equation. It does take a
> very long hang to clean up the sound. The short hang time is apparently
> what was causing the clipping and the "crunched" sound due to severe loss
> of dynamic range.
>
> I made a new recording that I will place on my website later that
> demonstrates how AM sounds when the settings are changed. I recorded a 40
> meter short-wave broadcast station on both receivers simultaneously with
> the 870 in the left channel and the O2 in the right. I split the channels
> and made separate MP3 files of each radio. I also backed off the
> bandwidth of 870 and matched the O2 so the -3 dB points were at the exact
> same frequency. Both receivers were fed from a T connector to the same
> antenna. The results were outstanding! The only noticeable difference is
> the AGC action, and that the O2 handled the really deep fades better than
> the 870.
>
> Good work TT! I'll mark that off the 'fix' list...
>
> Ron N6IE
> www.N6IE.com
> (Formerly N6AHA)
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
>
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