Hi Whiskey - thanks for taking a look. This is raw IQ data stored as a wav file. The way I open these is to set my SDR software (in my case SDR#) source to "IQ File (*.wav)" and then, once it loads, make sure to set the tuner to the frequency of interest - in this case 462.0 MHz. If its still not playing through your SDR software, maybe the file got jacked. Anyone else have success playing my IQ through their software?
Unidentified signal at 462.000 MHz
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Hi Whiskey - thanks for taking a look. This is raw IQ data stored as a wav file. The way I open these is to set my SDR software (in my case SDR#) source to "IQ File (*.wav)" and then, once it loads, make sure to set the tuner to the frequency of interest - in this case 462.0 MHz. If its still not playing through your SDR software, maybe the file got jacked. Anyone else have success playing my IQ through their software?
Thanks everyone for considering this. I am pasting below what the FCC actually reports as active licensees with transmitters in my area. If someone is better than I at interpreting the jargon in here, maybe you can shed some more light than I could. To help narrow things down - can anyone identify the type of modulation being used in this signal?
If I had to guess, this seems to be coming from the direction of Tenleytown/AU, but RF is voodoo so who really knows (short of me driving over there with a kit).
Call Sign/Lease ID | Name | FRN | Radio Service | Status | Expiration Date | |
|---|---|---|---|---|---|---|
| 1 | WPDS307 | American Airlines Group, Inc. | 0022661201 | YG | Active | 11/04/2023 |
| 2 | WPPY565 | COMMERCIAL COMMUNICATIONS INC | 0007403769 | IG | Active | 03/15/2025 |
| 3 | WQAM227 | DOCTORS COMMUNITY HOSPITAL | 0010406270 | IG | Active | 06/30/2024 |
| 4 | WQBC371 | Chevy Chase Club - Golf Maintenance | 0010932671 | IG | Active | 09/17/2024 |
| 5 | WQQG710 | Howard Hughes Medical Institute-JFRC | 0020893574 | IG | Active | 12/06/2022 |
| 6 | WQVL472 | Bear Communications, Inc. | 0004078838 | IG | Active | 03/18/2025 |
| 7 | WSO555 | MILLS COMMUNICATIONS INC | 0002162352 | IG | Active | 02/12/2023 |
If I had to guess, this seems to be coming from the direction of Tenleytown/AU, but RF is voodoo so who really knows (short of me driving over there with a kit).
freqhopping
Member
What I've found is that I receive 462.0 better closer to DC in southernmost Montgomery Co. In my estimation, it's not originating from Tenleytown, too weak.
I don't receive it at all in Loudoun without using my roof antenna.
I don't receive 452.85 or 453.95 at all at the same MD location. In Loudoun I can recieve 452.85 and 453.95 on the duckie and really strongly with the roof antenna.
I don't get DCS codes on any of these.
The signal on 462.0 is different that the others. None of the VA licenses seem likely.
Montgomery Co KGC807 453.95 includes the emission type 10K0F1D which includes LTI Automated Vehicle Location (AVL) system - LT6 Radio Modem / LTI Automated Vehicle Location (AVL) system - LT6 Radio Modem.
452.85 WRE227 is also licensed by Montgomery Co but voice only.
Maybe these are some sort of tracking for Ride On buses, school buses and other county vehicles.
I don't receive it at all in Loudoun without using my roof antenna.
I don't receive 452.85 or 453.95 at all at the same MD location. In Loudoun I can recieve 452.85 and 453.95 on the duckie and really strongly with the roof antenna.
I don't get DCS codes on any of these.
The signal on 462.0 is different that the others. None of the VA licenses seem likely.
Montgomery Co KGC807 453.95 includes the emission type 10K0F1D which includes LTI Automated Vehicle Location (AVL) system - LT6 Radio Modem / LTI Automated Vehicle Location (AVL) system - LT6 Radio Modem.
452.85 WRE227 is also licensed by Montgomery Co but voice only.
Maybe these are some sort of tracking for Ride On buses, school buses and other county vehicles.
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Thanks for running this down freqhopping. It was very helpful to have a second set of eyes from another point on the ground. So my best guess on 462.0 is Arlington, one of the FCC licenses WPPY565 (Commercial Communications Inc.) actually turns up on a fairly nearby transmitter. According to the license info, this station has four emission types on it, listed out below. Of these, the 462 MHz signal seems more consistent (at least to my amateur eyes) with a 7.6kHz bandwidth, and since I don't think its voice, my best guess (again, amateur/idiot here) is 7K60FXD 2-slot DMR (Motorola MOTOTRBO) TDMA data. DSD not helping. Still not sure about the 453.950 signal, but now that you mention AVL, I have seen similar looking UHF signals associated with WMATA's AVL system. Thanks again, let me know if you ever need me to check out a signal from here to return the favor.
11K2F2D--
Bandwidth: 11.2 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [2] Digital, with modulation
Information Type: [D] Data, telemetry, telecommand
Modulation Type Notes: F2D Data transmission by frequency modulation of a radio frequency carrier with an audio frequency FSK subcarrier. Often called AFSK/FM.
Emissions Designator Notes: 11K2F2D Audio frequency shift keying within a 12.5 kHz channelspace (commonly used for 1.2 kbps packet, FFSK station alerting, and AFSK tornado siren signaling)
11K2F3E--
Bandwidth: 11.2 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [3] Single analog channel
Information Type: [E] Telephony, voice, sound broadcasting
Modulation Type Notes: F3E FM speech communication – often used for marine radio and many other VHF communications
7K60FXD--
Bandwidth: 7.60 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [X] Unknown
Information Type: [D] Data, telemetry, telecommand
Emissions Designator Notes: 7K60FXD 2-slot DMR (Motorola MOTOTRBO) TDMA data
7K60FXE--
Bandwidth: 7.60 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [X] Unknown
Information Type: [E] Telephony, voice, sound broadcasting
Emissions Designator Notes: 7K60FXE 2-slot DMR (Motorola MOTOTRBO) TDMA voice
11K2F2D--
Bandwidth: 11.2 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [2] Digital, with modulation
Information Type: [D] Data, telemetry, telecommand
Modulation Type Notes: F2D Data transmission by frequency modulation of a radio frequency carrier with an audio frequency FSK subcarrier. Often called AFSK/FM.
Emissions Designator Notes: 11K2F2D Audio frequency shift keying within a 12.5 kHz channelspace (commonly used for 1.2 kbps packet, FFSK station alerting, and AFSK tornado siren signaling)
11K2F3E--
Bandwidth: 11.2 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [3] Single analog channel
Information Type: [E] Telephony, voice, sound broadcasting
Modulation Type Notes: F3E FM speech communication – often used for marine radio and many other VHF communications
7K60FXD--
Bandwidth: 7.60 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [X] Unknown
Information Type: [D] Data, telemetry, telecommand
Emissions Designator Notes: 7K60FXD 2-slot DMR (Motorola MOTOTRBO) TDMA data
7K60FXE--
Bandwidth: 7.60 kHz
Modulation Type: [F] Angle-modulated, straight FM
Modulation Nature: [X] Unknown
Information Type: [E] Telephony, voice, sound broadcasting
Emissions Designator Notes: 7K60FXE 2-slot DMR (Motorola MOTOTRBO) TDMA voice
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