RF Noise Generator
Design
- Useful as a filter test signal source
- Pass filters
- Crystal filters
- From Experimental Methods in RF Design
- Fig 7.72
- Described as "not flat"
- "Junk box" parts
- (2) 2N3904 transistors
- (2) 5V (nominal) zener diodes
- Noise figure -50 dBm @ 10 MHz
Schematic
Prototype
- Unique nodes in red
- Prototype on single sided copper clad PCB
- KiCAD zener packages have backwards silkscreen (will need to fix on OshPark PCBs)
Meaurements
- Background noise
- Generator off
- Average ~ -64 dB
- Noise Generator On
- Falls off with frequency, but better than -50 dB