Home Products HD-500

Hum Detector

Model HD-500 is a detector/amplifier designed to demodulate
the low frequency amplitude modulations on any RF carrier
over the range of 5 to 1500 MHz. Capable of measuring Hum levels less than -100dBC.

These modulations are usually the undesirable result of the 50 or 60 Hz power source and are not necessarily sinusoidal. The unit is calibrated to the SCTE definition of hum modulation, which is the
ratio of the peak-to-peak hum modulation to the peak of the carrier.
The magnitude of the demodulated signal is proportional to
the degree of modulation and independent of the carrier level
over a range of -10 to -50 dBm.

This unit has the option of being built into a rack mount
or a stand alone cabinet.

For more information, view the setup PDF.

RF Frequency Range 5 ~ 1500 MHz
RF Input Power Range -10 ~ -50 dBm
Input Return Loss < -15 dB, 50 Ω (75 Ω Optional)
Output Voltage

3000 mV peak to peak for -40 dBC Hum
300 mV peak to peak for -60 dBC Hum
30 mV peak to peak for -80 dBC Hum
3 mV peak to peak for -100 dBC Hum

Noise Floor < -105 dBC
Maximum Output Voltage 20V peak to peak
Modulation Bandwidth 5 Hz to 500 Hz
Internal amplifier provides linear phase response.
A 60 Hz square wave is produced with less than 2% tilt.
Power Requirements 100 ~ 240 V 50/60 Hz, 3A max
External Equipment Required 1 - A digital storage oscilloscope with signal-averaging capability.
2 - Carrier source with hum modulation levels lower than the levels that are to be measured.
Overall Accuracy ±1dB for carrier and modulation levels specified above.