Threat to Public Safety Communications

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radioconsult
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Threat to Public Safety Communications

Post by radioconsult »

:evil: My wife runs a cellular store at a local mall and a couple of weeks ago a new kiosk setup business selling the micro radio controlled race cars. While at the mall I took a closer look at the R/C cars and could not find any FCC approvals. The packaging leads me to believe that they were made in China for the European market. However, what is distrubing is that some are marked 27 MHz, no problem here. Some are marked 45 MHz., BIG problem. In Oklahoma the state DPS, Corrections, Wildlike and others operate in the 44 & 45 MHz. band. I can see a real potential for harmful interference if these things are being sold throughout the U.S. Yesterday I received a spam ad from Yahoo Store advertising the identical toys.

I was wondering how widespread this probelem may be. BTW I have sent a complaint to the FCC and also an note to Yahoo.

This may be an excellent opportunity for Batwingers to do a little mall investigation.
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Pj
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Post by Pj »

Although they are in that range, most power levels are so low, that's its not a problem. I doubt that it would have any great effect if you were trying to rx/tx on your portable while operating the RC car.

Still, they are operating out of the "RC band".
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EngineerZ
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Post by EngineerZ »

Pj wrote:Although they are in that range, most power levels are so low, that's its not a problem. I doubt that it would have any great effect if you were trying to rx/tx on your portable while operating the RC car.
Conversely, I'd like to see what happens to the RC car when a nearby state trooper keys up his 110W mobile low band rig... :-)

--z
RFdude
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Low power can go almost anywhere

Post by RFdude »

The license exempt rules now allow defined field strength limits almost anywhere. This is especially true for "momentary" devices like alarms. The thought was that if it is momentary AND low in power (nW), harmful interference is unlikely.

Under this type of scenario, FCC and IC approved Compustar two-way car alarms on 447.700 MHz. That is a repeater input frequency! :evil: Sure enough, some of these units are installed incorrectly, resulting in almost continuous transmissions. They claim a half mile range. The amateur repeater is unusable. The Compustar could have just as easily been approved on a commercial frequency, perhaps falling on a public safety service in your area. Once hundreds are out there in the hands of consumers, you can scream and lobby all you want, it is too late to save your frequency. See http://www.qsl.net/va3bmc for more information.

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007
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Post by 007 »

As it is, I already set off car alarms if I am tx'ing while driving past some vehicles. I wonder what the effect of 110w on 447.700 would be to the alarm system. Did anyone actually find a car with that alarm and find out??

**************************************************
EnginnerZ wrote:

Conversely, I'd like to see what happens to the RC car when a nearby state trooper keys up his 110W mobile low band rig...
**************************************************

(Texas DPS officer is patroling rural Sugarland, TX)

3772 Houston....

(trooper hears whining sound out the window, then looks out window while talking to see little RC truck racing out of control and, while little Johnny is trying frantically to regain control of his truck, slams into his mother bent over planting flowers in the garden)
Do not make Sig angry...he'll just keep ringing the bell.
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EngineerZ:::::

Post by CHEFA2001 »

:lol: :lol: :lol:
I almost choked on my drink when I read your post about keying up on the radio...........
BRAVO!!!!!!!!!! :evil:
EDACS - Every Day Another Customer Screams...So a few al-Qaeda tourists got locked without a trial in Camp X-ray? Pass the
Kleenex...BOO, HOO, HOO.....AMERICA Should have turned a large chunk of the world into a parking lot.
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Post by Threeshot223 »

Were they maybe mismarked? I know RC cars also run on 49MHz, so it's possible that it was a typo. I mean, we all know how well-trained the Chinese/English translators are in their jobs.
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phrawg
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Post by phrawg »

I have found another even more dangerous situation (IMHO).
Seems as tho the chineese are selling a series of cordless microphones
at extremely low prices. So low that even pawn shops are buying them and reselling at 29-39 dollars. They have a molded rubber
3 pin connector that has a molded in 2-3 inch long "antenna" that plugs
into where a normal mic cord would go. The connector houses a flea power xmiter. Then they have a reciever that goes with them to feed your mixer or amp. I have done some extensive research on these and even spoken to the FCC several times about them.
They say there fall under NO exemptions for power range etc. due to the band they are in. Are you sitting down ! (110-117 mhz AVIATION
NAVIGATION BAND !!!!!!!) they are 10-20 mw but at line of sight
what is that to an aircraft at 30k feet !!!!!!!!! I have given FCC web sites to see these and mfg. info but dont know what has been done. Just saw a few more of them a couple weeks ago and told the shop they better
pull them and buy no more and explained the situation. How about 3-4 airliners homing in on the local disco !!! :o :o :roll: :( phrawg
BBbzzzzz... ZAP.. GULP !!! ahhhh GOOD fly !
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Fun with pocket frequency counters...

Post by hfitzgerald »

I think it's time I dug up my pocket RF frequency counter (the little $100 MFJ model). This weekend looks to have an interesting trip to the mall.

Also on a side note, I heard from a 3rd party that some of the 'momentary' transmissions are allowed to sustain for up to 2 minutes. That sure doesn't sound like momentary to me, especially if it a commercial application on the 440 band.
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Post by ASTROMODAT »

Pretty soon, it won't matter: As soon as President Bush mops up Irag, Iran and N Korea, we're gonna' make glass outa China.

Larry
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Post by Salem The Cat »

phrawg wrote:I have found another even more dangerous situation (IMHO).
Seems as tho the chineese are selling a series of cordless microphones
at extremely low prices. So low that even pawn shops are buying them and reselling at 29-39 dollars. They have a molded rubber
3 pin connector that has a molded in 2-3 inch long "antenna" that plugs
into where a normal mic cord would go. The connector houses a flea power xmiter. Then they have a reciever that goes with them to feed your mixer or amp. I have done some extensive research on these and even spoken to the FCC several times about them.
They say there fall under NO exemptions for power range etc. due to the band they are in. Are you sitting down ! (110-117 mhz AVIATION
NAVIGATION BAND !!!!!!!) they are 10-20 mw but at line of sight
what is that to an aircraft at 30k feet !!!!!!!!! I have given FCC web sites to see these and mfg. info but dont know what has been done. Just saw a few more of them a couple weeks ago and told the shop they better
pull them and buy no more and explained the situation. How about 3-4 airliners homing in on the local disco !!! :o :o :roll: :( phrawg

What "extensive research" have you done ?

There is certainly an intrustion into the VOR frequencies (and by
definition, localizer and glideslope channels), but to an aircraft at
FL300, it's irrelevant. I suspect the FAA/ITU/FCC aren't worried
about RFI issues due to the low power levels involved and the need
to be in extremely close proximity to the transmitters for any type
of issue to make it's presence known.

20 mW is insignificant when a VOR radial or ILS by it's very nature
is very directional, and operating at a typical power level of 10 watts
(more if needed for ambient terrain compensation). Assuming for a
moment the "toy" radiates a signal that doesn't follow the inverse
square law, that R/C control would have to be awfully close to the
VOR/ILS antennas to cause any sort of problem. Close enough to
be drawing the attention of security personnel one would hope.

As a professional pilot, I'd be more concerned about the interference
potential of UWB devices. A new emerging RFI threat the industry &
to their credit, the FAA, is following very closely. At FL410 or FL350 I
don't care about the 20 mw toy being operated by somone in their
living room, as much as the gadget freak in the back running a UWB
equipped PDA, messing up my MLS or GPS navaids.
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Post by phrawg »

The research I have done is to find as many as I could of the names of the various companys and importers that are sending these things into the country. Thing I dont understand is the freq allocations are pretty much standard worldwide so how do they sell them in other countries unless like you say the signal level is insignificant which I agree with you on. I am sure that at those fl's the signal would be in the pico or nanno volt range. I was taking a bit of liberality about homing on the disco kinda to put a bit of humorous punch to what I was saying. Nonetheless the FCC told me there were NO "low power exceptions" in the aero bands so I still wonder where in the grey market they are slipping in. These things are not found in the toys sections. They are sold through "professional musicians suppliers" as
lower price versions of the properly designed and type accepted wireless mics. Brands like telex, shure, nady, senheiser, audio technica, etc
which stay in freq slots designated by the FCC for that purpose. nost of them are 174-216 mhz and there are 6-8 freqs available in each 6 mhz
slice that equals a tv channel 7-13. pick an unused tv ch in your area
and use the freqs in that slot. Thats how the wireless mics are
"coordinated". Maybe this is just another of the cases of "unless it bothers someone, dont stir the pot" oh well :roll: Phrawg
BBbzzzzz... ZAP.. GULP !!! ahhhh GOOD fly !
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Post by bernie »

My two bits worth:
I've had a problem much worse than that.
Trying to fing the source of intermittent very high receiver desens at two sites, I found the following.
It seems that Car rental outfits use wireless terminals to transfer customer data to the office. These are low power units, and the computer people, being (supposidly) totally ignorant of the existance of anything else on the band, picked a splinter channel between a community repeater accross the street to a hotel that could be seen accross the bay. It took a year to find them.

I also had an instance where the wireless terminal in the Eagle hardware store was on CH16 of the SMR on the mountain in clear view of the store.
It was spread spectrum, but was idle, so it "parked" on a single channel, that happned to be in use.

The visionaries at the FCC have the answer :Go digital.
Aloha, Bernie
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Post by Salem The Cat »

phrawg wrote:The research I have done is to find as many as I could of the names of the various companys and importers that are sending these things into the country.
Well, you're to be commended on your initiative. Perhaps you're going
about it the wrong way, with respect to who is being notified. The usual
regulatory agencies are more responsive to inquiries from elected
officials. May I suggest you get a hold of your senator and inform them
of your findings ? In this post 9/11 atmosphere, I'm sure you'd get
someone to take a peek at this real quick. An alternative would be to
call the local news station, they'd probably be more than eager to run
an "investigative" special on it.

Oh, and as a pilot, I would most definitely disallow usage of such toys
inside the cabin. On the ground is one thing, but inside the aircraft in
such close proximity to my antennas, the last thing I need if I'm flying
an ILS approach in zero, zero IMC , is a glitch to my glideslope and
localizer cues.

Actually there have been a few instances of ILS's being serviced &
flight crews flew a profile that would have put them into terrain (due
to erroneous guidance data from the ground). Fortunately the crews
caught the error and were able to divert a catastrophe. You'll never
hear about these incidents unless you peruse ASRS data.
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Post by RCVMO »

Many moons ago while traversing through one of our wild post teenage hot-spots, I was working 6 meter while driving through this rough terrain. I had noticed a small RC car dodging in and out of traffic and spotted the driver not too far away, but in an inconspicuous location. Once again, as I keyed the mic on my rig, for some unanswerable reason, the RC car decided to dart toward my vehicle. Needless to say, mini-van Vs. RC car?
CRRRRRRRRRRRUUUUUUUUUNNNNNNNNNNCCCCCCCCHHHHHHHH!!!!!!!!!!!!
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lowband adventures

Post by 007 »

Nice job with the RC killing!

I find great personal satisfaction in pulling up to ghetto cruisers with 1,000 watt sound systems and nuking them with 100w of 52.525...all you hear is a funny popping sound, then S**T from the driver.

X9000: $500.00

Antenna: $35.00

Watching wannabe-gansta wonder what just happened:

PRICELESS

:)
Do not make Sig angry...he'll just keep ringing the bell.
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Post by Jonathan KC8RYW »

007 wrote:Nice job with the RC killing!

I find great personal satisfaction in pulling up to ghetto cruisers with 1,000 watt sound systems and nuking them with 100w of 52.525...all you hear is a funny popping sound, then S**T from the driver.

X9000: $500.00

Antenna: $35.00

Watching wannabe-gansta wonder what just happened:

PRICELESS

:)
Hmm.

Does the RF kill the radio front end? I that the part that is affected?

What part of the system is taken out by the RF?

I don't see how this could happen?

RF levels would have to be pretty high to damage the actual circuits, right?

I don't have much expierence with using RF to cause bad things to happen. It's kind of what I like to avoid. :)

Anyone want to chime in, with expierence in this area (it's okay, I won't tell the DA :) ) ?
73 DE KC8RYW
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ASTROMODAT
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Post by ASTROMODAT »

I think 007 was talking about blowing out the guy's speakers with the huge humm, as opposed to burning out any of the audio circuits.

larry
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Post by RCVMO »

007, been there done that, only with a 110watt lo-band Micor. My ol' garage supervisor and I caught a grin after making a directional lo-bander antenna and sticking it out the garage door at the street. Let's just say it killed more than just the wannabe's. :lol:
Jimmy
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Re: lowband adventures

Post by OX »

007 wrote:I find great personal satisfaction in pulling up to ghetto cruisers with 1,000 watt sound systems and nuking them with 100w of 52.525...all you hear is a funny popping sound, then S**T from the driver.
Oh my gosh, that's hilarious! I laughed for ten minutes! Do you use that for free car washes too? (It's a rumor)
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Aero band

Post by Cowthief »

Hello.

The easy way to piss off the pilot.
FM pocket radios cover 88MHz to 108MHz correct?.
The IF is normally around 10.7MHz.
Cheap radios have excellent shielding, as per FCC, right?.
108+10.7=118.7.
Be careful who you tell this to, we do not need some dumb passenger,,,,,.
Thank You.
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Post by RCVMO »

OK, here's another one. While in our senior(senial) staff meeting this morning, it was brought to my attention that people who can't wait for the traffic light system, which is interlinked by a SCADA system have some device nowdays that can interrupt the traffic light timming. I still can't figure this one out, since ours is on a type II trunking system and having to chase down the SCADA signal, well, by that time the lights green for ya.,
Anyone know about this?
Jimmy
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SCADA

Post by Cowthief »

Hello.

The system in San Antonio, made by saftran,<SP?> perhaps merged,
uses a Z80 microproc', so, when put in, on the late 80s, I hacked it.
I did not know fully what SCADA was at the time, but that simply made this a learning game.
You will find that traffic signals WILL be hacked, you can only hope that you can form an alliance with them ( hackers ).
Remember, everything WILL be hacked, nothing you can do will change this, however, if you work with people, most will work with you.
With this in mine, the DEFCON group has a section devoted to hacking everything from traffic control signals to the highway warning signs, to the private electronic billboards, the things with moving messages, no one uses them anymore, kind of hard to promote beer when the sign has been hacked.
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SCADA

Post by Cowthief »

Almost forgot about this.
You want to track down that SCADA signal?,

http://www.imperioustech.com

There are others, but this one is perhaps the best, needs nothing more than a cable connection.

Have fun?!.
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more lowband adventures

Post by 007 »

bubbasnest:

I never tried the carwash trick...really :)

It is the speakers that get affected most of the time...however in one case this summer, a pal of mine and I teamed up at an intersection while having a perfectly legal conversation on 52.525 and managed to get one honda's sounds system to fail completely.

The head unit nuked, the sub box speakers nuked, and he must of had some neon or something in the car, because everytime we'd key up his interior would glow blue and green...unless we were doing some kind of electro-plating of the steel ??

Needless to say, he really flipped out. :evil:
Do not make Sig angry...he'll just keep ringing the bell.
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Post by Jonathan KC8RYW »

Does anyone think that a low pass filter at around 300 Hz would stop RF at 52 MHz from creeping into the speaker on the speaker wires?

Maybe some bypass caps and beads on the wires?

Still, most speakers (especially woofers) have a large coil on them. I doubt it would help.

Does anyone want to try this experiment out? :)
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RF in 'da spek-kaz

Post by Cowthief »

Hello.

What seems to be the problem.
RF gets into the speaker amp, this is 'cuz looks kewl and all, amp.
The amplifier is mouted so everyone can see your amp, and the "monster" cable, twin lead, just one slight problem.
I have found that, for the most part, "normal" radios have not this problem, I wonder if, someone were to make a beam, 52.525MHz, rock concert?.
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Post by Code3Response »

OK - whats up with the 52.525 mhz? Why is it the magical one? :). What other naughty things may be done with it? :lol: :lol: :lol: :lol: :lol:
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Post by mancow »

Oh, it's not the only one. 10 meters (29mhz) works well too. My neighbor's guitar amp had an extreme aversion to this frequency. But, I agree that 52.525 just seems to have a reliable effect for whatever reason. It also seems to creep into the IF section of bendix king radios. When I would key up my vx7r on 52.525 the audio would be heard clearly on every channel perfectly. (vhf models).

Anyone else have any stories? I'm tempted to try the 525 thing on the next boomboom car I see. Would an Icom 706 or FT100 have the muscle to do it.

Hmmm how may power inverters would it take to power my KW amp mobile??? 8)


mancow
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Post by JAYMZ »

The 52.525 trick is funny....I would love to ride through Monticello and do that....but I would unfortunately be massively outnumbered.

When working in EMS our 110 watt VHF Maratracs would open the doors to the ER from anywhere within a 3 block area. Made for sweet revenge on the cold snowy nights when they would b*tch for bringing someone in.

"410...324 up and available.....ER doors open and awaiting next patient..."
JAYMZ

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Post by 007 »

Mancow-

Good info on the Bendix King radios....our DNR runs those on VHF. Nice to know that now...thanks for that b4 I cause any headaches!

Myself, my pals and the above-mentioned Honda driver know that a FT100 will work just fine...that is what a few of my pals have. The 525 trick works great when used with a properly tuned 2m 5/8w or 6m 1/4w from Larsen. :o

I don't have any operational experience with the '706, but if it's a 100w, I would think so.

We did find one thing out, though....don't try it with a Diamond/Comet dual/triple band antenna - doesn't work for *%&^
It must be something with the matching coils or something?

I think this summer I may have to try to videotape some of the 525 action without the little punks knowing it.

"007's Lowband Adventures" ????

Might be worth finding out just how much I can squeeze out of the X9000's PA for a night :D
Do not make Sig angry...he'll just keep ringing the bell.
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Post by Radio_Cowboy »

007 wrote:

"007's Lowband Adventures" ????



I just got a GREAT mental pic of James Bond, rolling through Ghettoville in his Aston Martin with a Lowband X-9000 in it (Complete with 1/4 wave ball mount antenna on the left rear fender) on a mission to blow up all the boom-boom car's radios and speakers.....*ROTFL**LOL**LOL*
:lol: :lol: :lol: :lol:


-RC-
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Post by mancow »

OH that video would be great. Kind of like a techincal jackass. And quite legal I would think. I mean your're well within you're rights to talk on 525 at 100 watts. It's their fault their crappy equipment cant handle it.

mancow
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Post by 007 »

I'm seriously considering putting a lowband 1/4w ball mount on my Impala...it's so egregious that I just might do it. :o I already have a rhino pushbar on it....


It's not an Aston Martin, but the effect would be the same!
Do not make Sig angry...he'll just keep ringing the bell.
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Post by Radio_Cowboy »

Is it one of the New Impala's? I have seen that the Illinois State Police are starting to use those new Impala's, and they still use Lowband with the 1/4 wave ball mount antenna on the rear fender...... First time I saw that I thought the car was gonna tip over in the wind! :o



Also makes it fun to go to Dayton.....Where else in the world can you see someone put a ball mount in the rear fender of a brand new Mercedes (ok, I can't spell it....I will never own one, so I'm not worried about it) 5 series and have 3 hustler HF antennas sticking out of it? :(


Or the 1974 Dodge van with 20 antennas on the roof AND a 18" DSS dish? :o


I think it's almost as much fun to walk around the parking lot and just check out some people's install jobs... :-?

Gotta love Dayton! 8)



-RC-
Y'all are just Jealous that the voices only talk to ME
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Post by 007 »

Yeah, it's a new Impala...what side did ISP mount the antenna on?

When I was out with CHP in June...I asked about the switch to roof mounted NMO mounts for the lowband radios, and it seems it was for money savings and less RFI with the laptops and vehicle computers.

I think it would be cool to have it anyway, and I bet it works a helluva lot better than a NMO !!

The whip really isn't that long, and if I get the black ball and spring, it really wouldn't stick out -that- much.....

110w into that antenna...this could be fun 8)
Do not make Sig angry...he'll just keep ringing the bell.
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Post by Radio_Cowboy »

http://www.angelfire.com/film/policecar ... s/ISP.html


Found this on the web




The Indiana state police still use lowband for the time being (untill the new Safe-t system gets up and going) and they switched from the ball mount to NMO mounts on the rear fender as well.




-RC-



-RC-
Y'all are just Jealous that the voices only talk to ME
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Post by Jonathan KC8RYW »

I just want to give a simple note on the subject of causing harmful interference to the public in the ham bands.

I suspect that myself and other hams (and most likely ARRL, and the FCC) probably will be asking themselves why they are providing hams with so much spectrum, which is in high demand, if a bunch of hams are deliberatly transmitting and causing severe interference (to the point of damaging other's property.) Do these actions seem like they might not be in the whole "spirit" of the ham hobby?

We, as a hobby, are supposed to be willing to help the public out, not hindering them in their daily life. We all know that the people of this country certainly do not need another enemy against them, while they are attempting to go about their life.

It seems rather drastic to destroy someone's personal property, simply for perhaps violating local noise ordinaces, which would be a civil infraction, not much unlike jaywalking or parking tickets. There are people in uniforms that carry badges that might be willing to take action on the vehicle in question, if asked.

I won't do any judgement calls or call anyone in particular wrong. No one is in the wrong. I have accused no one for doing anything wrong. I don't want to see anyone else accuse anyone else of wrong doing.

I simply figured I'd put these idea out on the "coffee table" so to say, for people to notice and consider when they have a moment.
73 DE KC8RYW
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Post by 007 »

I will mull over the ideas above while I program my X9000 and change the oil in my boomboom killer...will post my thoughts later.
Do not make Sig angry...he'll just keep ringing the bell.
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No, this is not right.

Post by Cowthief »

Hello.

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... =928670840

Look at the freq range!.
This is not intermit' part 15, this is crazy!.
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mancow
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Post by mancow »

What's next? ILS and Glideslope freqs. ? geez..
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007
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Post by 007 »

That's nice...I hope he doesn't live as close to a major airport as I do.
Do not make Sig angry...he'll just keep ringing the bell.
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ricciticcitembo
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Post by ricciticcitembo »

Well, as for the "boom boom" systems, I might be classified as having one myself. Although I would argue it because I try to tune the system to the best of my ability to mimic a set of studio monitors. It has a relitively flat response. It does however have one 12 inch subwoofer in a sealed box in it, and If I ramp up the gain on the Bass amplifier, it booms and will beat most ghetto systems with 2 12's or even two fifteen inch subs. The amp will easilly pop a 20 amp fuse INLINE WITH THE SPEAKER. I don't know exactly how much current the Amp draws as 14.4 VDC, but at a high volume, it kicks a 100A breaker everytime. Needless to say I DON'T run the system like that. I have a 40 Amp fuse inline with the breaker and I run the whole system off of that one fuse. That would be the Head unit/3 audio amps/2 45 Watt Spectra's.
The Spectra's audio is routed to the car stereo system as well with a small mixer I built.

I have been mixing Car Stereos with 2-Way radios for about 15 Years or so now.(ever since I was a kid) And let me tell you that the whole 52.525 thing is no joke indeed. It WILL kill a system.
And Yes I have killed a few of My own Audio Amplifiers with my own Transmitters. Two to be exact- 1) An Orion HCCA 225 Amp killed with my Yeasu FT-530 HT on two watts with a rubber duck talking to my friend on the local repeater. As soon as I keyed up the HT, smoke started pouring out of my trunk. That Amp cost $800 Dollars. Good thing I knew someone, and Got It fixed for free at the Factory. 2) A Blaupunkt BPA 350 killed with my Motorola Saber VHF in a SVA hooked to a 1/4 wave NMO roof mount. I fixed this Amp myself, and it still in the Saab and is now working with the Saber fine. Some of the (8) Mosfets were bad (shorted)in the Powersupply. I replaced them with a radio shack Butane Soldering Iron with the amp still wired to the car. And All I did to remedy this little problem from reacurring was to firmly BOLT the amplifier to the trunk with 4 screws. As opposed to just laying on the carpet. I never tried to use the Orion with a transmitter again. It just costs too much.
Now Because I'm not new to this little irratating fact about 2-way and stereos, When I went to put in my system in the van I took some extra precautions. Some of U may remember my Missle can Idea. Well it turned out to be too small. So I welded in a 19" rack mount to the floor of my van. (after removing the fuel tank of course) I welded it completely around the perimeter face down, and it is a shallow rack like 7 inches deep used originally as a store demo effects display rack. It is 18 gauge Steel. In it I placed the Two Spectra's on another steel shelf, and placed the Audio Amps (2 Alpines and an 800 Fosgate)right next to the Spectras in the same Steel box although seperated by that shelf. All the wiring was done with Double shielded twisted pair. Heavy duty Belden Mic wire is what I used. 18 Gauge for the signal, and 16 Gauge for the speakers. It is grounded at the box with the end near the speaker floating. For the signal the shield and black wire are connected together at both ends.
Well, I am satisfied. I can key up on either the 800 or UHF Spectra or the VHF Saber with a 35 Watt RF Amp in the SVA with NO Problems! And lets not forget that the audio from the Spectra's/SVA is mixed with the head unit on receive. All antenna's are 1/4 Wave and have Flat SWR per band per unit. One to each radio. And since I don't have a LB unit yet, I went over to my friends house who has a ramsey kit 6 meter hooked up to the back end of a LB Micor. Man that thing is NASTY! He has already blown up a few "boom boom" systems with that. I was hesitant, but I just had to find out..... He called CQ and got someone on the calling channel, and after that switched to the local repeater and my van survived. And it was near the antenna too. I really don't know sh*t about 2-ways, but i can tell you this much- Shielding/grounding and Lots of Steel or mu-metal helps alot to prevent damage to your own equipment. I have had the same setup in my house too. Solid Steel 19 inch rackmount. Transmitters/tranceivers at the bottom of the rack. Vaccuum tube preamps/ AD/DA converters near the top. Video monitors in the middle along with test equipment. Everything gets along fine, and I can talk to my radio buddies while recording something which is important to me. I hope this helps others who would like to be able to use their ham radio and watch TV at the same time. Or listen to the traffic report in their car.
Thanks. Dave
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007
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Post by 007 »

Radio_Cowboy wrote:http://www.angelfire.com/film/policecar ... s/ISP.html


Found this on the web

-RC-



-RC-
I stumbled over that site last night at work, too....I emailed the guy and asked him for the full picture of the Impala..he sent it to me about 10 min. later.......that is one helluva big antenna for that car!! I'm gonna have to completely lose my mind or be sloshed to mount that on mine. I just can't see doing that to a year old car!

In this case, big signal = BIG holes. I think the NMO mount will work just fine.
Do not make Sig angry...he'll just keep ringing the bell.
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007
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Post by 007 »

007 wrote:I will mull over the ideas above while I program my X9000 and change the oil in my boomboom killer...will post my thoughts later.

Getting on my box now:

Insofar as furthering the hobby, Jonathan is right - knowingly using my ability to transmit a signal that will most likely destroy/disable something is not something to be proud of. I have done it only 3 times, and the first 2 were by accident because I didn't put 2+2 together.

However, when one is surrounded by little cars that cost 10K and have and additional 15k in modifications done because the 17 yo driving it thinks he's cooler than the rest, my level of sympathy for that group of people is rather low. I'm all about having toys, but I'm not going to limit my conversations on 6m to times when I'm 1 mile away from everyone else.

Will I go around trying to destroy others audio systems on purpose - no way. In this area, I'd probably get shot at...that's a choice I don't like, on or off duty. We have one road that goes thru a few cities that the "cruisers" like to frequent during the summer. I also drive to and from work on this road. If there happens to be some incidental damage that occurs while I'm on 6........oh well.

I'm not forgoing my hobby to allow a bunch of young punks to have ego contests at every stop light. I'm only in my mid 20's, and I never saw a reason to have a car that was "fly" or a sound system that you could 2 blocks away. Sure, I put an upgraded system in my first car, but it was for my enjoyment, not those outside of the car.

I'm done :o
Do not make Sig angry...he'll just keep ringing the bell.
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Radio_Cowboy
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Post by Radio_Cowboy »

Damn JW,

and here I was hopeing to see you blast one of them big ol ball mounts in your new car.... :) ISP runs 42 MHZ, you will be running 52-53 MHZ....it will be a LITTLE shorter.....c'mon... and be sure to post pics if you do decide to go with the 1/4 wave.


I agree with you on the boom boom topic.... I don't like that type of music myself, and it personally wouldn't hurt my feelings to see a few of them get toasted, but I'm not going to go out and do that on purpose. I won't let it limit my hobby either, however.


I'd like to get on 6 meters.....prolly eventually pickup a lowband Syntor X or X-9000, but it's too close to christmas to be blowing more money on toys.



-RC-
Y'all are just Jealous that the voices only talk to ME
Cowthief
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What's next

Post by Cowthief »

Hello.

ILS?, Glideslope?.
How's about a few watts.

http://longrangecordless.com/cordless/258.html

I think that, if this stuff gets out enough, somone IS going to crash, yes, something WILL get done.
I feel that, like sept 11, the reaction will be overreaction, perhaps even to the point of "executing" ham radio.
Let's get together, figure how much of a threat this really is, if it is even legal, part 15, or other, and what needs to be done, this can be good for our hobby, or bad, just depends on what we as a group and singular, are willing to do.

Thank You.
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phrawg
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Post by phrawg »

Read the specs close both the base and mobile xmit on 390mhz and recieve on 254mhz HHHhmmhmmmmmm dont think thats gonna work very well !!!!!! The cordless mics that were referenced earlier
are the ones I was commenting about in the first 7-8 posts or so of this thread. There is a lot of unaccepted S**T getting in to the country these days for sure. I have found most of it to be chineese garbage. Phrawg
BBbzzzzz... ZAP.. GULP !!! ahhhh GOOD fly !
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007
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What radios do you own?: W7 FPP lowband MaraTrac w/AES

Post by 007 »

Radio_Cowboy wrote:Damn JW,

and here I was hopeing to see you blast one of them big ol ball mounts in your new car.... :) ISP runs 42 MHZ, you will be running 52-53 MHZ....it will be a LITTLE shorter.....c'mon... and be sure to post pics if you do decide to go with the 1/4 wave.

-RC-
It -may- happen yet...I've been staring at that full pic of the ISP Impala for 2 days now, it's to the point that it's the pic on my desktop now. :o

It's so obnoxious that I may just have to do it....my car won't be worth squat when I'm done with it anyway, so I'm not concerned about retail value.
Do not make Sig angry...he'll just keep ringing the bell.
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