Cheap wireless microphone's Receiver specification:

Recieving System:Fixed frequency by quartz controlled

Recieving Sensitivity:60dB S/N ratio.(12dBU)

S/N Ratio: >100dB

Audio output level:

Unbalanced mode of CHA+B:0~0.5V/5KΩ

Unbalanced mode of CHA+CHB:0~0.5V/50KΩ

Power supply:AC 110V or 220V.(±10%)

The sum settle to consume power<10W

Dimensions:420(L)X240(W)X45(H)

Working distance:200 feet

Microphone:

RF Power output:15mW(MAX)

Spurious Emissions: Over 45dB carrier ware

Microphone element: Unidiretional dynamic microphone

Battery:Standard 9V battery AA

Current consumption:About 25mA

Battery life:Over 8 hours continuous operation

Dimensions:52(D)x247(L)m/m

Weight:227gs

OVERALL SYSTEM

Carrier frequency range:

VHF high band 220-270MHZ

UHF 400-880MHZ

Frequency stability:±0.05%

Modulation Mode:FM

Maximum deviation range:±25KHz

Frequency Responses:40Hz-15KHz

S/N ratio:>100dB

Audio dynamic range:>100dB

T.H.D:≤0.5%

Service areas:150 meters

Temperature range:-10°C~50°C