Sinisa,
Thanks. That burst of signals also explains my main beef with the sweep
(other than the flakiness and related problems that others have seen), the
fact that decreasing the sweep range, doesn't increase the sweep resolution
as it does on the Icom 756 series.
Mark
----- Original Message -----
From: "Sinisa Hristov" <shristov@ptt.yu>
To: <tentec@contesting.com>
Sent: Monday, September 20, 2004 10:54 AM
Subject: Re: [TenTec] Orion sweep
> Mark Erbaugh wrote:
>
>
> > Has anyone looked into how the sweep is actually done in the Orion
hardware.
>
>
> Signal path is as follows:
>
> * board A3:
> * first mixer (Q1-Q4)
> * amplifier (Q24)
> * pre-roofing crystal filter (X1, X2)
>
> * board A4:
> * source follower (Q17)
> * two stage amp with local AGC (Q13, Q14)
>
> * board A13:
> * main/sub RX selection (D900)
> * AD9200 ADC (U900) (10 bits, 20 Msps, SNR 57 dB)
> * 32 K x 8 RAM (U902)
>
> * board A7:
> * XC95288XL CPLD (U3) (also generates ADC/RAM control signals)
> * MC68EZ328 CPU (U1)
>
>
> Therefore, a burst of samples is acquired into RAM,
> and later transferred to main CPU for processing,
> subject to CPU loading.
>
>
> 73,
>
> Sinisa YT1NT, VA3TTN
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|