[Scan-DC] Request for assistance: WB Telemetry signal on about 223.50 MHz

[Stephen Platt]

Comments embedded:
----------------------------------------
I'd like to request any reports or knowledge of a 'wideband' telemetry
signal that was on approximately 223.5 MHz this past Wednesday evening from
sometime prior to 1700 local until it abruptly ended at about 1737 hours
local.  During the time I was listening to it, it had one carrier drop, but
only about one half second in duration.
-----------------------------------------------------------------------

This also happened in Norfolk/Hampton area after 1600 and before 1800. 
------------------------------------------------------------------------

 Because I was in the car (and driving!) while the signal was on the air, I
was not able to make a detailed analysis of its frequency, but it appeared
centered somewhere around 223.5 MHz.  Modulation extended up at least as far
as 223.880 MHz (380 kHz), because it was about 'third scale' on that
frequency and distorted, when the W3VPR repeater in Davidsonville was off
the air.  The signal was causing harmful interference to stations receiving
the repeater output, at least in the Crofton / Davidsonville area.  Other
amateur stations that were on 222 MHz at the time in Anne Arundel County
heard the signal and confirmed its sound and strength. 
--------------------------------------------------------------------------

I had full scale readings on 223.5 as well as 220.0 with simultaneous weaker sigs (I was assuming spurs) throughout between 219 and 225 MHz. It was audible on the Hampton WB4PVT 224.54 machine. When the repeater timed out it was still audible on the output. It seemed to cycle 4 minutes on followed by 4 minutes off and repeating. 
----------------------------------------------------------------------------
 
When tuned to 223.5 MHz, the signal seemed to be sending 4 or 5 tones
"randomly" in a rapid but discernable rate (almost similar to an old
'bagpipe' jammer, but faster).  The same cadence could easily be detected on
223.880 MHz. 

The signal on about 223.5 was EXTREMELY strong along US Route 50 from the
RT424 Davidsonville Road exit all the way east to the Parole Exit in
Annapolis.  It was so strong, I never saw the signal strength bar report
anything other than full strength on a Kenwood TM-742 transceiver equipped
with a trunk mounted Larsen half wave mobile antenna until the signal went
off the air around 1737 local.  
 
If anyone else heard this yesterday, or has heard it previously and knows of
its source, I'd appreciate knowing.  Thanks and 73
 
John...
-------------------------------------------------------------------------------------------------------------

I'd like to know what that was as well. perhaps some government test gone awry. Being this occurred near USNA and 
NAVBASE NORVA at the same time perhaps something with the USN? 

Stephen Platt KC4JGC