GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase...
Transcript of GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase...
![Page 1: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/1.jpg)
GPS Locking the IC 910-H
By RexMoncur
VK7MO
![Page 2: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/2.jpg)
BLOCK DIAGRAM
GPSDO
PLL & 30.2
MHz Osc
IC 910-H
10
MHz
30.2
MHz
![Page 3: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/3.jpg)
External Oscillator Input
![Page 4: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/4.jpg)
Circuit Mods to IC 910-H
![Page 5: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/5.jpg)
Internal Mods to IC 910-H
![Page 6: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/6.jpg)
30.2 MHz Oscillator and PLL
![Page 7: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/7.jpg)
PLL Block Diagram
![Page 8: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/8.jpg)
PLL Construction
![Page 9: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/9.jpg)
Stability at 1296 MHz
1 Hz
Receiver &
SigGen
locked to
separate
GPSs
Receiver &
SigGen
locked to
same GPS
50 mHz
![Page 10: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/10.jpg)
Phase Noise v Loop Time Constant
Tc= 20 micro-seconds
Phase Noise at 5 Hz = -55 dBc/Hz
1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Blue = HP SigGen
Tc= 3000 micro-seconds
Phase Noise at 5 Hz = -45 dBc/Hz
![Page 11: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/11.jpg)
Phase Noise with Oven Oscillator
1296 MHz: Yellow = Oven Oscillator, Blue = HP SigGen
Phase Noise for both at 5 Hz = -70 dBc/Hz
10 Hz off
10 Hz off
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5 Hz Phase Noise at 1296 MHz
•161 PLL with Hi-Q Osc -55 dBc/Hz
•RigLockwith Hi-Q Osc -58 dBc/Hz
•161 PLL with Oven Osc -70 dBc/Hz
•HP SigGen -70 dBc/Hz
•10 GHz DB6NT Trans. -34 dBc/Hz
![Page 13: GPS Locking the IC 910-H small - VK3HZvk3hz.net/riglock/VK7MO_GPS_Locking_the_IC 910-H.pdfPhase Noise v Loop Time Constant 1296 MHz: Yellow = PLL with cheap Hi-Q Oscillator, Tc= 20](https://reader033.fdocuments.in/reader033/viewer/2022050413/5f89d6df996ba755b01d6b39/html5/thumbnails/13.jpg)
CONCLUSIONS
•Need a good quality oscillator to get
lowest phase noise.
•Hum can be a problem –mount in
shielded box and bypass liberally with
electrolytics.
•Stability is better than 0.1 Hz at 1296 MHz
and more than adequate for JT65a.
•Accuracy is better than 1 Hz at 1296 MHz