Broadcast FM Whistling

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Broadcast FMFrequency Modulation Whistling
BroadcastFM Whistling 2.JPG
Frequencies 102 MHzMegaHertz (MHz) 10^6 Hz102,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
102,000 kHzKiloHertz (kHz) 10^3 Hz
Frequency Range 102000000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).102,000 kHzKiloHertz (kHz) 10^3 Hz
102 MHzMegaHertz (MHz) 10^6 Hz
102000000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).102,000 kHzKiloHertz (kHz) 10^3 Hz
102 MHzMegaHertz (MHz) 10^6 Hz
Mode DSBDual Side Band Modulation
Modulation
Location
Short Description

I was scanning FMFrequency Modulation radios when suddenly I found this.

Possible solution: Hobbyist single-transistor tracking transmitter.
I/Q Raw Recording
Audio Sample

Additional Images[edit]

BroadcastFM Whistling 1.JPG BroadcastFM Whistling 3.JPG

Solution: Probably single-transistor SAW oscillated TXTransmit, probably hobbyist. Data input and/or Vcc of TXTransmit seems to be discharging a capacitor which is periodically fed a charge pulse; doing that to a single transistor TXTransmit results in exactly this, a signal that gradually drifts it's frequency while lowering it's amplitude. This can be used as a tracking transmitter, compatible with USBUpper Side Band Modulation (Radio, referring to reception and modulation mode)Universal Serial Bus (Computer, referring to USB Ports and cables) mode; it could be for a lost RC plane finder for example. The lower/higher pitch tone audible at the fadeout-spot, and the louder the general volume, the closer it is.