PERFORMANCETESTS

MODEL 8559A

 

PERFORMANCE TESTS

4-15. RESOLUTION BANDWIDTH ACCURACY

SPECIFICATION:

Individual resolution bandwidth 3-dB points are calibrated to +15% (+30% for 3 MHz bandwidth).

DESCRIPTION:

Resolution bandwidth accuracy is measured in the linear mode to eliminate log amplifier errors. Since signal level at the 3-dB points (half-power points) is related to peak signal level by a voltage ratio of 0.707:1.O, a peak level of 7.1 vertical divisions on the spectrum analyzer display gives a half-power level of 5 vertical divisions:

0.707 (voltage ratio) = X div/7.1 div

X div -=(7.1)(0.707) 5 div

In the 30-, lo-, 3-, and l-kHz bandwidths, a 21.4 MHz signal (final IF) is injected directly into Bandwidth Filter No. 1 Assembly A11 to provide the stability required for measurement of narrow resolution bandwidths.

SPECTRUM

ANALYZER

SIGNAL GENERATOR

ADAPTER P

 

PADAPTER

FIGURE 4-9.RESOLUTIONBANDWIDTHACCURACY TEST SETUP,3 MHz TO 100kHz

EQUIPMENT:

 

Signal Generator .........................................................

H P 8640B

Extender Cable Assembly ..............................................

H P 5060-0303

Adapter, Type N (m) to BNC (f) (2 required) ...............................

H P 1250-0780

Adapter, Type SMB (f) to BNC (f) .......................................

H P 1250-1236