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WJ-9195 RASP
Rapid Acquisition Spectrum Processor


pan/sector display



newer WJ-9195C

WJ-9195 RASP System

The original WJ-9195 RASP unit was an advanced Digitally Refreshed Display (DRD) unit that controlled a specially modified WJ-8617B to generate a display. It consisted of:

WJ-9195/DRD-1 - Digitally Refreshed Display (middle unit in photo above) - functions as scan controller and processor for a specially adapted WJ-8617B receiver.

WJ-9195/CRT (top unit in photo above) - standard NTSC display monitor in slick WJ cabinet.

WJ-8617B-2 or WJ-8618B-15 (shown - bottom of rack) - specially modified WJ-861xB series receivers for rapid spectrum scanning. The WJ-9195 will not function with any other WJ receivers.

The WJ-8617B-2 or WJ-8618B-15 have specially modified fast settling synthesizers to allow the fast scanning mode and special control codes in the GPIB interface. See the WJ-8617 and the WJ-8618 version guides for more details on the -2 and -15 variants of these two receivers.

WJ-9195/DRD-1 Pan/Sec Display

The display on the WJ-9195/DRD-1 is called "pan-sector." The top trace on the screen displays a 5 MHz "sector" of the range centered on the tuned frequency of the receiver. The five following traces display are a "pan" of the entire 20-1100 MHz in five bands. Spectrum activity is displayed in 25 kHz chunks, like a long and detailed bar graph of the spectrum.

The number at the top of the screen (153.15 in the photo) is the center frequency of the WJ-861xB series radio in the system. The radio cannot receive at that frequency when the DRD is generating spectrum but the DRD can hand this frquency off to other receivers if demodulation of activity is desired.

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The newer WJ-9195C sharpens the resolution to 5 kHz and allowed for programming the end points on the bottom five traces.
The WJ-9195C is much smaller. It is the same size as the CRT unit in this system and sports an electroluminescent touch screen.

WJ-9195/DRD-1 Keyboard


The unit is relatively simple to operate with an uncluttered keyboard hinting of opions my unit did not have. It is capable of handing off a signal spotted on the CRT display to other WJ-8617B, WJ-8618B or WJ-8615 receivers through GPIB.



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RASP System rear panel



The connections for the WJ-9195 system are very straightforward, needing only two BNC to BNC cables, one for video and one for IF and a GPIB cable. The system has a second GPIB controller that can be be connected to a computer for control of multiple RASP units.





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