What can the power supply do to my signal, and how do I stay safe?
The power supply
Two power-supply faults show up on the air.
- A poorly regulated power supply causes frequency instability (chirp) in CW.
- A defective power-supply filter capacitor causes superimposed hum or buzz in transmitters and receivers.
So the cause of superimposed hum on a transmitted or received signal is a defective filter capacitor in the power supply.
RF safety
Large amounts of UHF or microwave RF energy can damage body tissue because of the heat produced: the body's water absorbs the energy.
Before working near a high-gain UHF or microwave antenna, make certain the transmitter cannot be operated.
You now know
- A defective filter capacitor causes hum or buzz; a poorly regulated supply causes chirp.
- UHF and microwave energy can damage tissue by heating, as the body's water absorbs it.
- Before working near a high-gain UHF or microwave antenna, make certain the transmitter cannot be operated.