[FARC] [Fwd: inadvertent sig on 73]

[Bob Moroney]

All,

Here's an email that Rolan W3FDK has asked me to post to the reflector.  
There's been a spate of interference on the FARG 146.73 repeater, 
apparently caused by a mobile rig being inadvertently keyed on the 
frequency, with the proper offset and PL tone and a good bit of power. 

Suspicion is that the rig is powered up whenever the ignition is on, and 
someone is sitting or leaning on the mike without knowing it's there, 
pressing the push-to-talk switch and transmitting for a period of time.  
Faint voices and other people noises (e.g. nose-blowing) have been heard 
in the background, along with music from a satellite radio and other 
car-type sounds like seatbelt or key-in-ignition alarms.  I suspect that 
the rig's speaker volume is low and whoever is in the car doesn't hear 
other transmissions or the W3ICF repeater IDs.

Please look at the times this interference has been noted, the DF 
results, etc. for any patterns you might recognize - it could be someone 
you know! 

Any additional reports should be sent directly to Rolan 
(rolan.clark at comcast.net) and Phil W3ICF (w3icf at comcast.net).

73, Bob K9CMR

-------- Original Message --------
Subject: 	inadvertent sig on 73
Date: 	Fri, 13 Jun 2008 08:59:51 -0400
From: 	Rolan O. Clark <rolan.clark at comcast.net>
To: 	Many, Many Hams in Area

	



QST
 
FARG group here, Rolan W3FDK at the keyboard, and we have a mobile unit 
that appears to be sitting on a microphone and transmitting to our 
146.13/73 repeater and Phil. W3ICF did most of the writing here and I 
will add my part. Remember when Phil says today he means Thrusday, June 12.
 
 From Phil:
 
The problem started on Sunday at around 1425 and cleared in about 1440. 
Per my beam it started in the south direction and moved through west and 
end in a near north direction.
Later on Sunday about 1809 it came in again but appeared to start North 
and ended South, once again about a 30 min run.  One report at 1811  
showed a plus 9 signal in Frederick. Another report gave a 5 to 9 s- 
meter reading in Mt. Airy from a mobile unit setting in his driveway. 
After about 30 minutes it cleared out again.
 
Monday it showed up again but a little earlier around 1250  and cleared 
about 20 minutes later.  It then reappeared around 1600 and cleared in 
about 20 to 30 minutes. I always show about the same level readings. 
 High from south then Full scale and fade out in the North Direction. 
The next event seems to be the return trip, North to South with about 
the same reading from the beam. I do not remember hearing it on Tuesday 
and Wednesday but was busy and could have missed it.
 
Today, Thursday, it started at 1050 cleared for a min or two at 11:05 
and then came back. By 1112   it was gone and stayed off until 1320 .It 
came back on so I shut down the repeater at 1325  and headed for the Van 
to look for it. Once again it cleared out and has not been back on so 
far today.  It sounds like some one has the mike switch resting against 
something causing it to key up. Most of the time it stays keyed until 
they get out of range or park the vehicle. I was able to hear some one 
talking and it seemed they were on a cell phone. K9CMR, Bob also 
reported a women talking on Monday and a car door alarm went off but 
with the radio covering up most of this, we could not tell who the 
voices belonged too.
 
( Rolan,W3FDK here, today, Thursday,  when I got home at about 1340 Phil 
had called and we did this, I live south of Frederick about 6 miles so I 
left home with my mobile, 25 watts and a 3 dB mag mount on the roof, 
went east 6 houses, turned right on New Design Road and went to RT 28, 
turned left and took RT 28 to RT 85, turned left on RT 85 and went to 
Frederick, then I 270 to MD 121, MD121 to RT 355, then RT 355 to 
Frederick. All the while I would transmit and check with Phil while he 
took bearings and relative signal readings and that is how we got a 
similiar signal profile to what Phil has been tracking from home with 
his beam, we think it is the 355 or 1270 route that is traveled most of 
the time )
 
(Rolan, W3FDK here, I think it was on Monday that I monitored 146.13 
while it was on and I drove from my home 6 miles south of Frederick to 
Frederick via  US15/US340 and lost it around Frederick so I headed home 
and just out side of Adamstown it came on again, I turned around and 
this time I took Mountville Road up over the ridge towards Jefferson and 
of course the signal got strong on the ridge but I lost it completey 
just a 100 feet or so west of the peak so I went down to Lander Road, 
turned left towards Point of Rocks then took Frye Road to RT 464 and 
turned left on that to US15 just north of Point of Rocks, I could hear 
the signal weak at that point so I went across the US15 bridge a few 
miles into Virginia and turned around at a high piece of flat ground and 
I couldn't hear the signal then so I came back to MD and took MD28 at 
Point of Rocks to New Design Road then north on New Design Road to 
Adamstown Road where I live and I was starting to get stronger but I 
lost it completely before I got home and it never came on again that day.)
 
(Rolan, W3FDK here, I like Al, KB3MKJ's observation that the radio must 
be connected to the ignition key because it seems to go on and off with 
car use unless the mic is wedged between seats somewhere and the weight 
of someone in a seat compesses the seat and puts pressure on the mic 
ptt, who knows)
 
 
 
The radio station on the car is a Sirius Chan 123 but today the Chan was 
182 both seem to be Punk rock station.  Poor music in my mind HI.
 
Rolan and I ran simplex test and it appears that a mobile moving from 
around Clarksburg shows up as South on my Beam and moves to West Full 
Scale and fades out North around Urban to FSK. The signal levels on 355 
read about the same as when I monitor the Music. 270, 85 Point of Rocks 
do not match the beam readings or the S-meter reading like the ones on 
355.  Sure wish we could find out who it is and make them aware they are 
transmitting music on the 146.73 repeater so we have to keep taking it 
off the air.
 
Some time later today between 1530 and 1600 hours it came back in and I 
started down route 75 to see if I could detect a reading on 355. At 
RollingGreen just before 355 the s- meter in the Van indicated full 
Scale by the time I turned onto 355 it was gone. Al KB3MKJ was reporting 
a full scale reading at his place. I went out Brownville road and the 
signal was full scale but cleared out before I got to Route 27 in 
Damascus. Bill reports from his site the Beam antenna indicates South 
Eastern direction and this tracks with my readings.  I drove by the 
Damascus Fire house and ask them to have Doug Noble give me a call. 
Would like to have him check with the folks down there.
 
All I know at this time is it seems to be a young couple  with small 
children and the vehicle is equipped with a Sirius radio and 2 meter 
transmitter set on 146.73 with PL 146.3. It appears that problem comes 
in when they start the car and stops when they turn it off. Something is 
keeping the transmit keyed any time the radio is on and that appears to 
be controlled by starting the car. All of this is pure speculation.
 
(Rolan, W3FDK here, we don't care who it is, just want to help us of 
course and them also as they don't realize what is happening and that 
thing I am sure has or can happen to all of us in some form or another.)
 
Please coordinate all inputs with Phil, W3ICF, he has the best feel for 
all the scenarios and has been beam tracking this signal profile  and 
one contact person is the best way to go.
 
Good luck and thanks to all who can help,
 
FARG,
 
73 es tnx rolan w3fdk