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
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