Attachment #1 shows the schematic of the test setup. Signal generator (Marconi) was used to supply the RF input. We observed the IF output in the following three test conditions.
- Observed the spectrum with FM modulation (fcarrier of 40 MHz and fmod of 221 Hz )- a peak at 221 Hz was observed.
- Observed the noise spectrum without FM modulation.
- Observed the noise spectrum after disconnecting the delayed output of the delay line.
- It is observed that the broad band noise level is higher without FM modulation (2) compared to that we observed after disconnecting the delayed output of the delay line (3).
- It is also observed that the noise level is increasing with increase in RF input power.
- We need to find the reason for increase in broad band noise .
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