[Wswss] Situation Report One (SITREP 1) 52.525MHz Continuous Strong Signal (*)(Grid DM04)

[n6ze at aol.com]

Situation:


Very loud, continuous signal noted on 52.525MHz in Ventura Co., CA area (Grid DM04) during week of 15 – 21 March 2009. At least 14 amateur radio operators submitted/posted reports of reception of the signal. All responders, except one, reported moderate to very strong signals (as much as 50 dB above noise floor). Reception reports were received from grids (*) DM04jf, DM04jg, DM04le, DM04me, DM04mf, DM04nd, DM04ne, DM04ng, DM04od, DM04of, DM13at. Bearings of signals appeared to be Northerly in most cases. The report from DM04le indicated a very weak signal peaking to North. One responder traveling in an automobile noted strong signals along US-101 from DM04ne eastward to DM04pd with weaker signal coverage noted as far east as Burbank, CA (DM04ue). Another responder traveling in an automobile on US-101 from Thousand Oaks (DM04ne) toward Camarillo (DM04me)  noted that signals decreased to less than 6 dB above noise floor during the descent down the US-101’s “Conejo Grade” to Camarillo Springs and signals again became strong when clear of hills just to the north of the “Conejo Grade”. Some fixed stations noticed signal flutter/QSB when aircraft at low altitude flew past their locations;  some mobile stations noted typical mobile flutter/QSB on the signals also as they moved about. One responder with hand-held FM receiver with ‘rubber duckie’ antenna conducted three mile walk in city residential  area of DM04ne on 20 March: signals sometimes broke through squel
ched receiver, and always could be heard weakly with squelch disabled.

The 52.525MHz signal could be weakly received when a hand-held FM receiver with ‘rubber duckie’ antenna was held close to a Verizon F.I.O.S. optical to TV/Internet/telephone adapter box located in a home garage. When a portable SSB receiver with whip antenna was activated in the same garage, the 52.525MHz signal was very strong, but became extremely strong when held close to the Verizon F.I.O.S. adapter box detailed above.

Equipment utilized by responders:


i.                     SSB receiver with horizontally polarized yagi antenna

ii.                   FM receiver with vertical antenna

iii.                  SSB receiver with whip antenna

iv.                 Hand-held FM receiver with ‘rubber duckie’ antenna


 Reception Details:


i.                     FM: Loud carrier, with nil modulation

ii.                   AM: Loud carrier, with nil modulation

iii.                  USB or SSB: very loud, raspy modulated signal

iv.          A
0      Visual Signal Scope: dB vs. Frequency plot about 3KHz wide with 3 very significant signal peaks at about 52.525MHz and +/- about 1.5KHz. Refer url:  http:qrz.com/n6ze for scope display.


Geography Details


i.                     Receiver antennae were located from about 20 ft above sea level  (ASL) to about 900 ft. ASL. 

ii.                   Surface topography varied from flat to hilly to mountainous. 

iii.                  Reception areas included rural (forest & parks), semi-rural, agricultural, industrial, suburban residential, and city residential.


Signal suddenly ceased at 2345Z (4:45PM PDT) on 21 March 2009. 

(*) Please refer to:     http://f6fvy.free.fr/qthLocator/fullScreen.php  for grid mapping information.



Action Taken:


i.                     18 to 21 March, this responder noticed loud signal on 52.525 MHz.

ii.                   Morning of 20 March posted notice of strong interfering 52.525 MHz signal at chat room/reflectors of: Ventura Co. (CA) Amateur Radio Society, Ventura Co. (CA)  Auxiliary Services (OES), Conejo Valley (CA) Amateur Radio Society, Western States Weak Signal Society, Pacific Northwest VHF Society, & 
Stanford VHF Reflector. Approximately one dozen amateur radio operators responded with reports.


Future Plans: Continue intermittent monitoring of 52.525MHz, the 6 meter FM Calling Frequency.

Recommendations: Request that ARRL’s RFI department contact Verizon’s F.I.O.S. Technical Department (or other possible sources) to determine cause of and cure for the strong 52.525MHz transmissions.


Regards,

Peter Heins, N6ZE (@arrl.net)

(ARRL-LM, past or present member of: CSVHF, WSWSS, PNWVHF, VCARS, CVARC, VTA, CA-ACS)