4-12 Max FM Deviation Tests
Performance Verification
4-34
PN: 10370-10386 Rev. B
MG362x1A MM
22.
Go to
.
23.
Wait approx 100 msec for FSWP to complete a full cycle of RMS FM measurement.
24.
Note FM RMS Deviation shown in the FSWP “Summary” window.
25.
Calculate Peak Deviation = 1.414*( RMS deviation).
26.
If Peak Deviation is < 10.133 MHz:
27.
Report “Fail” for the current mod rate. Set FM OFF.
28.
Set FM sensitivity = 11 MHz. Wait 10 msec.
29.
Go to
.
30.
Record the calculated Peak Deviation and FM Deviation setting for the current mod rate.
31.
If current mod rate is < 1 MHz, pick the next mod rate from the list and go to
.
32.
If RF < 20 GHz, set next RF freq (from list in
), wait 25 msec, go to
, using 10 kHz mod rate.
33.
If no Fails have been reported for any of the mod rates at any of the RF test frequencies, indicate “Pass”
for the overall test.
34.
Exit
Ext Low Noise FM Max Deviation – Mod Rates > 1 MHz
FSWP FM demod deviation accuracy is specified only up to 1 MHz rate. So, for mod rates > 1 MHz, FSWP
phase demod will be used to measure FM mod index. (Mod index = Peak phase deviation in radians). FM
deviation = (Mod rate)*(mod index), and mod rate is precisely known, so FM deviation can be accurately
determined from the phase deviation measurement. FSWP phase deviation measurement uncertainty is
0.0002*(1+measured deviation, rad). Allow 1 % margin for DUT variation.
For example, 10 MHz FM deviation and 2 MHz rate gives mod index = 5, i.e. peak phase deviation = 5 rad.
Phase deviation measurement uncertainty is 0.0002*(1+5 rad) = 0.0012 rad = 0.024 %. Adding 1 % margin for
DUT variation then makes the FM deviation test limit = (Sales spec + 1.024 %) = (10 MHz + 1.024 %) = 10.1024
MHz.
Test Setup
Connect equipment as shown in
FSWP:
Tab Analog Demod, Meas Config / Display Config / drag “PM Time Domain” to screen center. This will
replace FM measurement with Phase Mod measurement. The “Summary” Display will now show Phase Mod
results.
Set: Demod BW 80 MHz, Meas Time = 10 msec.
Demod Config / Demod / AF Coupling = AC
Demod Config / Demod / Unit / Phase Unit = rad
Scale Config = 2 rad/div.
Trace Config: Trace 1 Clear/Write, Linear, Smoothing = 1 %.
Trigger button: Set “PM Offline” as the trigger source. Sweep = Continuous
External Function Generator:
2 MHz, 2.0Vpp, Channel ON.
MG362x1A:
FM OFF, Low Noise FM mode, Ext FM, DC Coupled, Sensitivity = 11 MHz/V, FM ON.
Summary of Contents for Rubidium MG362 1A Series
Page 12: ...Contents 10 PN 10370 10386 Rev B MG362x1A MM ...
Page 16: ...1 9 ESD Requirements General Information 1 4 PN 10370 10386 Rev B MG362x1A MM ...
Page 30: ...2 6 RF Deck Assemblies Functional Description 2 14 PN 10370 10386 Rev B MG362x1A MM ...
Page 66: ...3 11 FM and Phase Modulation Calibration Calibration 3 36 PN 10370 10386 Rev B MG362x1A MM ...
Page 292: ...B 5 Self Test Messages Instrument Messages B 8 PN 10370 10386 Rev B MG362x1A MM ...
Page 293: ......
