Initial Stability Measurements of the Mark I IF Downconvertor Glenn Jones June 8, 2006

Test Setup

View inside the chassis

Baseline SA Stability T1,T2 are successive 38.5 s integrations with the input of the SA terminated in 50 ohms RBW = 5MHz, VBW = 1kHz, Averaging 100 ~0.01 dB variation agrees well with

Stability vs. Successive Integrations T1,T2,T3,T4 indicate successive 38.5 s integrations These plot shows the gain variation as these successive integrations are compared against each other Some correlation is present, particularly near 600 and 750 MHz

Stability vs. Jostling During Integration T1,T2 indicate successive 38.5 s integrations during which the chassis was violently jostled

Stability vs. Jostling Between Integrations T1,T2 indicate successive 38.5 s integrations. The chassis was jostled between integrations then left to rest

Stability vs. Temperature T1,T2 indicate 38.5 s integrations. The temperature was 32C for T1 and 40C for T2 The gain dropped at higher temperature and the change shows some structure which correlates with the structure in the system response The chassis may have been jostled somewhat during the measurement, or the temperature change may have caused some physical movement

SA Response vs. System Response Possible effect of SA gain variation on system response