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Title: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 08, 2021, 11:36:43 pm
Alright, so I have an interesting situation.

The background:

I live in a small 2nd floor apartment in a downtown area, and there is a restaurant right across the street. From the window in my small "music studio" (aka an 8'x8'x8.5' bedroom), I can look right out to the restaurant's sidewalk seating. The sidewalk across the street is probably only about 40' from where I'm sitting now typing this in the "studio". Additionally, the only parking for the restaurant is on the street just outside the restaurant, which is no more than 40' from my desk. On my desk is a mixer (Soundcraft Signature 12MTK), which then leads to a BSS FDS-310 active crossover, which feeds an active subwoofer and an amplifier powering two monitors.

The situation is this:

Twice now, a big Ram 3500 pickup with a massive antenna I believe to be part of a HAM Radio system has parked just outside the restaurant. It looks something like this:
https://www.n1fd.org/wp-content/uploads/2016/08/Ant-Scorpion-medium.jpg

The first time I saw it, it was as I was walking back up to my apartment, I noticed the huge antenna and thought it was interesting, if not excessive. The truck was just parked outside the restaurant with no one inside it. About 40 minutes to an hour later, I was sitting in front of my monitors with my system powered on, with audio coming through my mixer at about -24dB (the lowest level on the meter). My blinds are also drawn, so I cant see out the window. Out of nowhere, an overpowering signal that sounds like an apocalypse comes through my system, scaring the hell out of me and spiking the meter to +16dB!

I frantically pull down faders and freak out until it stops, then look out the window and see the pickup truck is gone.

Fast forward to tonight, I notice the same pickup truck parked outside. Nearly as soon as I notice it, I see the owner get in and start it up, so I run over to the "studio" to see what happens and confirm that the pickup truck was related to my anomaly.

A few seconds after the truck starts driving away, the same thing: an apocalyptic distortion that sounds faintly like radio chatter blasts through my speakers, peaking the mixer. Pulling faders down didn't seem to do anything, I had to turn off the amplifier to stop it.

My questions are:

1) What is the legality of this radio system? My understanding is that it's legal as long as the driver of the truck has a license, but surely driving though a city with a system like that is causing issues for more people than just me?

2) Exactly what component of my system is picking up his transmission? What can I do to mitigate this?

The mysterious part to me is that the audio system in my studio picks this up, but my girlfriend didnt report experiencing anything similar from the sound system I have set up in the kitchen with the exact same model of amplifer I have in my studio powering some bookshelf speakers in there.

I've experienced amplifers picking up faint radio signals before any my friends house who lives several blocks from a local radio station, but nothing like this! And why didnt the amplifier in the kitchen pick anything up?!

Well if anyone has bothered to read this far down, thank you! I'd love some insight from anyone more knowledgeable about what's going on in more technical terms, I'm curious about this.

Thanks,
Doug
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Holtzman on April 08, 2021, 11:55:22 pm
Alright, so I have an interesting situation.

The background:

I live in a small 2nd floor apartment in a downtown area, and there is a restaurant right across the street. From the window in my small "music studio" (aka an 8'x8'x8.5' bedroom), I can look right out to the restaurant's sidewalk seating. The sidewalk across the street is probably only about 40' from where I'm sitting now typing this in the "studio". Additionally, the only parking for the restaurant is on the street just outside the restaurant, which is no more than 40' from my desk. On my desk is a mixer (Soundcraft Signature 12MTK), which then leads to a BSS FDS-310 active crossover, which feeds an active subwoofer and an amplifier powering two monitors.

The situation is this:

Twice now, a big Ram 3500 pickup with a massive antenna I believe to be part of a HAM Radio system has parked just outside the restaurant. It looks something like this:
https://www.n1fd.org/wp-content/uploads/2016/08/Ant-Scorpion-medium.jpg (https://www.n1fd.org/wp-content/uploads/2016/08/Ant-Scorpion-medium.jpg)

The first time I saw it, it was as I was walking back up to my apartment, I noticed the huge antenna and thought it was interesting, if not excessive. The truck was just parked outside the restaurant with no one inside it. About 40 minutes to an hour later, I was sitting in front of my monitors with my system powered on, with audio coming through my mixer at about -24dB (the lowest level on the meter). My blinds are also drawn, so I cant see out the window. Out of nowhere, an overpowering signal that sounds like an apocalypse comes through my system, scaring the hell out of me and spiking the meter to +16dB!

I frantically pull down faders and freak out until it stops, then look out the window and see the pickup truck is gone.

Fast forward to tonight, I notice the same pickup truck parked outside. Nearly as soon as I notice it, I see the owner get in and start it up, so I run over to the "studio" to see what happens and confirm that the pickup truck was related to my anomaly.

A few seconds after the truck starts driving away, the same thing: an apocalyptic distortion that sounds faintly like radio chatter blasts through my speakers, peaking the mixer. Pulling faders down didn't seem to do anything, I had to turn off the amplifier to stop it.

My questions are:

1) What is the legality of this radio system? My understanding is that it's legal as long as the driver of the truck has a license, but surely driving though a city with a system like that is causing issues for more people than just me?

2) Exactly what component of my system is picking up his transmission? What can I do to mitigate this?

The mysterious part to me is that the audio system in my studio picks this up, but my girlfriend didnt report experiencing anything similar from the sound system I have set up in the kitchen with the exact same model of amplifer I have in my studio powering some bookshelf speakers in there.

I've experienced amplifers picking up faint radio signals before any my friends house who lives several blocks from a local radio station, but nothing like this! And why didnt the amplifier in the kitchen pick anything up?!

Well if anyone has bothered to read this far down, thank you! I'd love some insight from anyone more knowledgeable about what's going on in more technical terms, I'm curious about this.

Thanks,
Doug


My guess is that's not a ham operator it's a CB person running a splattery linear amplifier.  Certainly that's illegal, getting the FCC to do anything about it, that's another thing.


Here's how you find out if it is a CB or a Ham.  Next time you see the truck stop by the restaurant and introduce yourself to the "operator" of the station.  Ham or CB they are both required to make sure their equipment is compliant and not interfering with other electronics.  If it's a ham operator they will be kind and have a discussion with you.  If it's a CB operator they will kick your ass and toss beer cans at you. 


What is it getting into?  My guess is it is illuminating anything that will act like an antenna, probably a couple kilowatts of power from DC to light. 



Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 12:43:34 am
Interesting, is "CB" this Citizen's Band radio I found on wikipedia?: https://en.m.wikipedia.org/wiki/Citizens_band_radio

Any idea why my sound system in one room picked it up but the stripped down system in the kitchen wouldn't have picked it up?

Is there anything I could add to my signal path to to prevent it picking this up? I remember watching a video a while ago from a HAM radio operator who installed ferrite chokes onto almost every wire in his house to filter out his transmissions from his phone line and such.

Considering how powerful this signal was though, it's hard to imagine that would do anything in my situation.

Is there any risk of damage to any components in my mixer? For some reason this feels like a dumb question, but if whatever this signal is can cause my mixers meter to instantly clip and blast distortion through the speakers it can't be healthy. It only last for several seconds though, not minutes.

I guess the simplest solution is to talk to the driver and ask him to wait until he turns is system on and politely let him know the interference its causing?

Thanks for the response, this gives me some stuff to look into!
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Holtzman on April 09, 2021, 02:04:28 am
Interesting, is "CB" this Citizen's Band radio I found on wikipedia?: https://en.m.wikipedia.org/wiki/Citizens_band_radio (https://en.m.wikipedia.org/wiki/Citizens_band_radio)

Any idea why my sound system in one room picked it up but the stripped down system in the kitchen wouldn't have picked it up?

Is there anything I could add to my signal path to to prevent it picking this up? I remember watching a video a while ago from a HAM radio operator who installed ferrite chokes onto almost every wire in his house to filter out his transmissions from his phone line and such.

Considering how powerful this signal was though, it's hard to imagine that would do anything in my situation.

Is there any risk of damage to any components in my mixer? For some reason this feels like a dumb question, but if whatever this signal is can cause my mixers meter to instantly clip and blast distortion through the speakers it can't be healthy. It only last for several seconds though, not minutes.

I guess the simplest solution is to talk to the driver and ask him to wait until he turns is system on and politely let him know the interference its causing?

Thanks for the response, this gives me some stuff to look into!


Yes, I was only being 1/2 funny when I said ask him to stop the behavior, if he is a ham operator he more than likely will be polite and refrain from operating his system in this manner.


On the other hand if he is a CB user then I doubt you will get a courteous response.


Can it damage your gear, oh yes, most certainly.  The much RF illuminates almost anything it can get into and radio waves are very tiny.  Chokes can help under normal circumstances but not the kind of field it sounds like they are generatining.


When I was a kid I had a dynamometer and a 500w tube linear in my car.  Keying that bad boy up in the drive through line would generally shutdown the headsets and reboot the registers.  One time one of the techs I worked with had a 150w VHF low band 6 meter GE Mastr II in his Bronco.  I had a 10kva Lorain UPS in the service bay that fed specialized computers that controlled paging and mobile telephone transmitter and other land mobile gear.  The UPS had a couple of huge SCR (or triacs I forgot now) that chopped the DC from the batteries into AC.  The thing was so load it was unreal.  He pulled in to the bay and wanted to see if he could still hit the 6 meter repeater.  The RF got into the UPS and turned on both SCR's at the same time (probably TTL input lines so didn't take much) and crowbarred about 2000 amps of DC.  Giant fiberball came out of the UPS, it was impressive.  Think of what the low power computers in your studio gear that probably operate at 1/2 of CMOS voltages (or lower).  That much RF will turn on every gate, buffer and what not and certainly could fry something along with just directly overload it. 
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Russell Ault on April 09, 2021, 02:10:35 am
If you can (safely) photograph the antenna we might be able to tell you a bit more.

Judging by what you're describing (both antenna and experience) I'm with Scott that it's much more likely to be CB than Ham. Most mobile stations in the amateur service these days are VHF or UHF (so the antennas aren't typically very large) and FM or digital (which rarely decodes accidentally in a way that would allow you to identify the contents of the signal). Some amateur license holders do maintain mobile SSB HF rigs, but those would be the exception, rather than the rule.

As Scott mentioned, if it is a licensed amateur causing this interference, they'll likely be glad to know that there's a problem and will want to take steps to solve it, while if it's a CBer (who isn't required to hold a license anymore)...I wouldn't bother raising the issue.

As far as steps you can take, judging by what you've described (peaking metres on the console unaffected by fader moves) I'm at least 85% sure that it's the output-stage line amplifiers on the Soundcraft that are "receiving" the transmissions. (Fun aside: not sure about the Signature, but I did once accidentally feed phantom power into the main L-R out on a Soundcraft Spirit, which had no audible effect before or after but did express its displeasure by pinning the meters.) It's possible that this might cause damage to the console (although it's somewhat unlikely, since any damage would be heat-relate, and that should require quite a bit of heat), but I'd be more worried about possible damage to your speakers.

I'd start by checking to make sure all your cables and devices are grounded properly (since cable shields quickly turn into antennas if they aren't). Installing ferrite chokes on all the cables that are plugged into the console (including the power cable it it doesn't already have one) certainly wouldn't hurt anything (chokes act as low-pass filters, which means even modestly-sized ferrite beads can still produce significant attenuation at higher frequencies).

Since the BSS crossover has a grounded electrical connection (and therefore should be supplying a proper signal ground reference), something else you can try is lifting the ground from the console end of the those cables, which will hopefully discourage any RF transduced by the cable shields from heading towards the console.

Finally, if you're feeling adventurous, you can try swapping the mic cables in your system for unshielded twisted pair cables (e.g. Cat5e). This is unorthodox, but in situations where you have a combination of differential audio connections and equipment grounds that can't cope with the RF they're taking on (assuming that is, in fact, the problem), eliminating the cable shielding can drastically reduce the overall RF being sent to ground.

-Russ
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jeff Bankston on April 09, 2021, 02:42:46 am
Thats a CB radio antenna on the truck. My dad was a big time Ham operator and involved in emergency communications. Ham radio is low power and does not interfere with AV stuff. CB radios with cheap lineir amps can interfere but your audio equipment is also part of the problem. You do not need a license to operate a CB anymore. I had a license in the 70's but the FCC did away with the requirements. You need a license to operate a ham radio. I have a top of the line CB radio and a kicker for use on the open road when needed. You can buy a lenier amp just about anywhere and they are legal to sell. Good luck complaining to the FCC. About 20 years someone near the interstate hid a CB radio jammer. "We" reported it to the FCC and were told do to a limited staff it could take a year or more to investigate it. Most people like me with CB radio use it when traveling for immediate weather and traffic info the all the modern internet stuff doesnt have. And there are places on I-10 in Texas and other places that do not have cell service and a CB radio will get you help. Nothing will ever be able to replace the CB radio not even a computer in your vehicle. 
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 02:50:28 am
This is very interesting information and definitely above my head in terms of electrical circuit knowledge, I appreciate all the help. I just got a bread board and started messing around with recreating circuits from schematics and learning about RC and LR circuits, simple filters, decoupling capacitors, etc so I'm very interested in this as as learning experience.

Regarding the ferrite chokes: it's my understanding the ferrite density and number of wraps around the choke need to be calculated somehow, but in this situation throwing anything on there would help?

What really confused me is that it did seem like the signal was being picked up inside the mixer rather than in the amplifier powering the speakers which is what I would have expected. The only cables running into the mixer at the time if the most recent occurence were all unbalanced. The AC power cable going into the mixer does not currently have a ferrite choke.

What makes the amplifiers at the end of the mixers internal signal path most susceptible to the RF transmission?

The antenna looked like this (with loose coils at the base and straight up after that), except it extended closer to 10' from the truck bed: https://ae01.alicdn.com/kf/HTB111E5n4uTBuNkHFNRq6A9qpXat/OSHINVOY-CB-radio-whip-antenna-26-28MHz-CB-27MHz-magnet-mount-antenna-26-28MHz-car-roof.jpg
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jeff Bankston on April 09, 2021, 02:54:49 am


The antenna looked like this (with loose coils at the base and straight up after that), except it extended closer to 10' from the truck bed: https://ae01.alicdn.com/kf/HTB111E5n4uTBuNkHFNRq6A9qpXat/OSHINVOY-CB-radio-whip-antenna-26-28MHz-CB-27MHz-magnet-mount-antenna-26-28MHz-car-roof.jpg
Thats a base load antenna. My Wilson cell antenna and mobile internet antennas look just like that one and have base load coils. The old classic non coil CB antenna is a 102" stainless whip.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Holtzman on April 09, 2021, 04:09:51 am
Thats a CB radio antenna on the truck. My dad was a big time Ham operator and involved in emergency communications. Ham radio is low power and does not interfere with AV stuff. CB radios with cheap lineir amps can interfere but your audio equipment is also part of the problem. You do not need a license to operate a CB anymore. I had a license in the 70's but the FCC did away with the requirements. You need a license to operate a ham radio. I have a top of the line CB radio and a kicker for use on the open road when needed. You can buy a lenier amp just about anywhere and they are legal to sell. Good luck complaining to the FCC. About 20 years someone near the interstate hid a CB radio jammer. "We" reported it to the FCC and were told do to a limited staff it could take a year or more to investigate it. Most people like me with CB radio use it when traveling for immediate weather and traffic info the all the modern internet stuff doesnt have. And there are places on I-10 in Texas and other places that do not have cell service and a CB radio will get you help. Nothing will ever be able to replace the CB radio not even a computer in your vehicle.


Jeff, it is not legal to sell an amplifier for Citizens Band per Part 95 of FCC regulations.  You are limited to 4 watts AM or 12 watts SSB.  It is also illegal to connect a 10 meter amateur linear amplifier retuned for 11 meter CB operation.


Amateur HF operations with a General license are allowed high powered operation 1500 Watts IIRC.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jeff Bankston on April 09, 2021, 04:26:53 am

Jeff, it is not legal to sell an amplifier for Citizens Band per Part 95 of FCC regulations.  You are limited to 4 watts AM or 12 watts SSB.  It is also illegal to connect a 10 meter amateur linear amplifier retuned for 11 meter CB operation.


Amateur HF operations with a General license are allowed high powered operation 1500 Watts IIRC.
As far as i have been informed its legal to sell amps. You can buy them online, i have seen them in CB section in truck stops, a CB radio shop here in socal sells them. If they are still illegal the feds are not inforcing the law. In the 70's many CB radio guys in south mississippi had tall antennas in their yard with tube amps connected to their CB. I never knew of anyone to get busted.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jeff Bankston on April 09, 2021, 04:32:31 am
It might not be a radio causing interference. A hot rod I had would make TV's go crazy when i pulled up in driveways. The high performance ignition system and non resistor spark plugs were probably causing the problem. When I got a different hot rod with a different ignition systenm the problem went away. Also the cell fone charger I have in my truck makes my AM radio go crazy when I plug it in. Also a defective CB radio or hot rodded CB radio can only cause interference when the mic is keyed up.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 09:38:28 am
Quote
It might not be a radio causing interference. A hot rod I had would make TV's go crazy when i pulled up in driveways. The high performance ignition system and non resistor spark plugs were probably causing the problem. When I got a different hot rod with a different ignition systenm the problem went away. Also the cell fone charger I have in my truck makes my AM radio go crazy when I plug it in. Also a defective CB radio or hot rodded CB radio can only cause interference when the mic is keyed up.

Jeff,

I doubt this is the issue in this case. Since I live at a busy downtown intersection, all kinds of vehicles pass by my window regularly and frequently, from a Ferrari to an 18-wheeler and nothing of this sort has ever happened before this particular pickup truck.

Could this burst be occurring as he leaves and maybe "checks in"? I'm not exactly sure what the common practice is over the airwaves.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Chris Hindle on April 09, 2021, 12:23:36 pm
Jeff,

I doubt this is the issue in this case. Since I live at a busy downtown intersection, all kinds of vehicles pass by my window regularly and frequently, from a Ferrari to an 18-wheeler and nothing of this sort has ever happened before this particular pickup truck.

Could this burst be occurring as he leaves and maybe "checks in"? I'm not exactly sure what the common practice is over the airwaves.
"XM-2384 reporting 10-8" XNZ-45 was the base station, on a private frequency......

My Dad ran the 444 radio division of the St. Johns Ambulance Brigade here in Montreal, and was disaster coordinator for Eastern Canada.
As a kid, I saw some weird shit.....
I was there when the town of Mirabel was leveled by various fire departments, practicing their art on real buildings.
Light it, put it out, light it, put it out. etc...
then a useless international Airport was put there......

In November 1963, just after 6:30 one night, we got a call at the house. Dorval Tower called. They lost a DC-8 near Saint Therese, and wanted him and his guys to go up and see what they could do.
It was a fucking crater.

Chris.

Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jason Glass on April 09, 2021, 01:22:14 pm
Alright, so I have an interesting situation.

An idiot blowing out nearby electronics with a ridiculous linear CB amp might actually get some attention from the FCC if you file a complaint.  It's a long shot, but that is actually an important part of their job.  Try to get photos of the vehicle, antenna, and license plate, but be discrete and don't provoke him.  You can attach them to your online complaint filing.  Try to record video with sound of your rig freaking out.  You might ask your neighbors if they're experiencing similar trouble, and if so, encourage them to also file complaints online.  The more who file, the more likely you are to get help.

https://www.fcc.gov/consumers/guides/filing-informal-complaint (https://www.fcc.gov/consumers/guides/filing-informal-complaint)
https://consumercomplaints.fcc.gov/hc/en-us/requests/new?ticket_form_id=38844 (https://consumercomplaints.fcc.gov/hc/en-us/requests/new?ticket_form_id=38844)
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Holtzman on April 09, 2021, 02:49:10 pm
It might not be a radio causing interference. A hot rod I had would make TV's go crazy when i pulled up in driveways. The high performance ignition system and non resistor spark plugs were probably causing the problem. When I got a different hot rod with a different ignition systenm the problem went away. Also the cell fone charger I have in my truck makes my AM radio go crazy when I plug it in. Also a defective CB radio or hot rodded CB radio can only cause interference when the mic is keyed up.


Maybe the field office didn't get real involved but they certainly busted the shops.  This is not a grey area.  Some famous operators were busted too.  The folks still selling them are very clever to note they are for 10M operation. 


37cfr95 clearly states:



95.939 External radio frequency power amplifiers (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e85365a752cb56982718af1895ea9321&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) prohibited.The operator (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=a44bb35fd35a922dc3098eef5d17b7a6&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) of a CBRS station (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e104882884fdeef3adf4d845809eff6c&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) must not use an external radio frequency power amplifier (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e85365a752cb56982718af1895ea9321&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) to increase the transmitting (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=48a87e5c08caa689a51b8a364e509d5d&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) power of that CBRS station (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e104882884fdeef3adf4d845809eff6c&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) under any circumstances. There are no exceptions to this rule.[/size][/font]
[/size](a) The FCC (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=b1f4d5a9d43407d945a50e775c6d7fe7&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) will presume that the operator (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=a44bb35fd35a922dc3098eef5d17b7a6&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) of a CBRS station (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e104882884fdeef3adf4d845809eff6c&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) has used an external radio frequency power amplifier (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e85365a752cb56982718af1895ea9321&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) in violation of this section if it is in the operator (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=a44bb35fd35a922dc3098eef5d17b7a6&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939)'s possession or on the operator (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=a44bb35fd35a922dc3098eef5d17b7a6&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939)'s premises and there is other evidence that the CBRS station (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e104882884fdeef3adf4d845809eff6c&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) has been operated (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=f01ba411bf951682a95242ac1a5e3d41&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) with more transmitting (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=48a87e5c08caa689a51b8a364e509d5d&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) power than allowed by 95.967 (https://www.law.cornell.edu/cfr/text/47/95.967).[/size]
[/size](b) The operator (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=a44bb35fd35a922dc3098eef5d17b7a6&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) of a CBRS station (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e104882884fdeef3adf4d845809eff6c&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) must not attach an external radio frequency power amplifier (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e85365a752cb56982718af1895ea9321&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) to a certified CBRS (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e5dc68272394490bf560d11dbf3ea9e2&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939) transmitter (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=33cab938403bcd4fbce8133b859edbd7&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.939).[/size]
[/size][/color]
[/size]Further:[/color]
[/size][/color]
95.967 CBRS (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e5dc68272394490bf560d11dbf3ea9e2&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) transmitter (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=33cab938403bcd4fbce8133b859edbd7&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) power limits.[/size]Each CBRS (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=e5dc68272394490bf560d11dbf3ea9e2&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) transmitter type (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=c5c2f12bb35362b7cf9261b6b8c904eb&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) must be designed such that the transmitter (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=33cab938403bcd4fbce8133b859edbd7&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) power can not exceed the following limits:[/size]
[/size](a) When transmitting (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=48a87e5c08caa689a51b8a364e509d5d&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) amplitude modulated (AM) voice signals, the mean carrier power must not exceed 4 Watts.[/size]
[/size](b) When transmitting (https://www.law.cornell.edu/definitions/index.php?width=840&height=800&iframe=true&def_id=48a87e5c08caa689a51b8a364e509d5d&term_occur=999&term_src=Title:47:Chapter:I:Subchapter:D:Part:95:Subpart:D:95.967) single sideband (SSB) voice signals, the peak envelope power must not exceed 12 Watts.[/size]
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 07:50:21 pm
UPDATE:

The truck came back and is currently parked outside, I left a couple friendly post it note on his window. If I see him leaving, I'll run out and have a word.

Pictures:
https://www.dropbox.com/s/cjbowvwmksm24jm/20210409_191106.jpg?dl=0
https://www.dropbox.com/s/o2kmti6w2q19rhs/20210409_191219.jpg?dl=0

Further plot twist:
It appears by the discreet lights hidden in the truck' grill and a testimonial from my neighbor who "recognizes" the truck that this may actually be a police officers private vehicle. I wonder how that changes the situation...

This time he decided to show up while my Powersoft amp rack is out preparing in Armonia+ for a small last minute gig.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 08:17:48 pm
UPDATE #2:

He turned out to be a very nice and understanding guy. At first he was hesitant to admit it was CB and said it was HAM, but we ended up having a nice conversation about his rig and I told him what was happening inside my studio. He ended up showing me his rig in the back seat and holy crap, this amplifier was monstrous and more ferrite than I've ever seen at one time in my life. He claimed the system was 15KW RMS and that he communicates with people in Puerto Rico from here in Maryland. He also has a multi $10's of thousands of dollar licensed HAM rig at home and does emergency communication.

So I guess we could have had a worse ending to this story, thank you for all the advice everyone.

Doug
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Holtzman on April 09, 2021, 09:32:29 pm
UPDATE #2:

He turned out to be a very nice and understanding guy. At first he was hesitant to admit it was CB and said it was HAM, but we ended up having a nice conversation about his rig and I told him what was happening inside my studio. He ended up showing me his rig in the back seat and holy crap, this amplifier was monstrous and more ferrite than I've ever seen at one time in my life. He claimed the system was 15KW RMS and that he communicates with people in Puerto Rico from here in Maryland. He also has a multi $10's of thousands of dollar licensed HAM rig at home and does emergency communication.

So I guess we could have had a worse ending to this story, thank you for all the advice everyone.

Doug


15kw out of a vehicle?  Was he towing a 15kw generator?  Come on you are smarter than that.  Glad the guy was nice, full of shit, but nice.


Antenna voltage and currents are harder to calculate than audio but figure roughly 800 volts at 17 amps.  Even if he could dead key (that's some of that them thar CB talk) 15kw and source the current that would be one rolling NEEPA violation. 


How about he just stops?  That much power is not going to help him talk a whole lot farther than 300 watts.  Once you get out of line of site you are at the whims of the gods of atmospheric propagation.  Much like audio watts don't matter much!



Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 09:49:39 pm

15kw out of a vehicle?  Was he towing a 15kw generator?  Come on you are smarter than that.  Glad the guy was nice, full of shit, but nice.


Antenna voltage and currents are harder to calculate than audio but figure roughly 800 volts at 17 amps.  Even if he could dead key (that's some of that them thar CB talk) 15kw and source the current that would be one rolling NEEPA violation. 


How about he just stops?  That much power is not going to help him talk a whole lot farther than 300 watts.  Once you get out of line of site you are at the whims of the gods of atmospheric propagation.  Much like audio watts don't matter much!

Unfortunately I doubt someone thousands and thousands and thousands of dollars invested into a hobby will just "stop". I wish I had some pictures of the equipment in the back, it was definitely interesting. My first guess was about 400 watts based on the linear amps I saw for sale when I started browsing, but hey I wasn't there to question his rig, but just relieved he wasn't a total asshole!
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Scott Helmke on April 09, 2021, 10:39:38 pm
Next time you see the guy, give him a friendly warning that Biden has hired Hillary to track down CB-using patriots, and that they're able to spot high powered CB amplifiers from Chinese satellites.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 09, 2021, 10:43:39 pm
Next time you see the guy, give him a friendly warning that Biden has hired Hillary to track down CB-using patriots, and that they're able to spot high powered CB amplifiers from Chinese satellites.

Amazing how you  nailed this guy's character!
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Russell Ault on April 09, 2021, 11:10:01 pm
UPDATE #2:

He turned out to be a very nice and understanding guy. At first he was hesitant to admit it was CB and said it was HAM, but we ended up having a nice conversation about his rig and I told him what was happening inside my studio. He ended up showing me his rig in the back seat and holy crap, this amplifier was monstrous and more ferrite than I've ever seen at one time in my life. He claimed the system was 15KW RMS and that he communicates with people in Puerto Rico from here in Maryland. He also has a multi $10's of thousands of dollar licensed HAM rig at home and does emergency communication.

So I guess we could have had a worse ending to this story, thank you for all the advice everyone.

Doug

If he is a licensed amateur (and intends on remaining so) then either he or you accidentally moved a decimal place: the FCC limits amateur tranmissions to a maximum of 1.5 kW peak envelope power (which is still enough to cause nearby electronics to do funny things, especially at lower frequencies). That's also a much more reasonable power figure for a station in the mobile service (once duty cycle is taken into consideration, anyway).

-Russ
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Douglas Cyr on April 10, 2021, 12:45:33 am
If he is a licensed amateur (and intends on remaining so) then either he or you accidentally moved a decimal place: the FCC limits amateur tranmissions to a maximum of 1.5 kW peak envelope power (which is still enough to cause nearby electronics to do funny things, especially at lower frequencies). That's also a much more reasonable power figure for a station in the mobile service (once duty cycle is taken into consideration, anyway).

-Russ

He definitely said 15KW, and he claimed his home system ran off two 60AMP 220Volt circuits.
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Russell Ault on April 10, 2021, 01:30:30 am
He definitely said 15KW, and he claimed his home system ran off two 60AMP 220Volt circuits.

Well, license enforcement in the amateur service (or CB, for that matter) is basically entirely complaints-based; maybe he just hasn't pissed off the wrong people.

Not sure why someone would spend (or, as Scott Holtzman pointed out, waste) that kind of cash with the knowledge that one false move could bring the FCC banhammer down on him.

-Russ
Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jeff Bankston on April 10, 2021, 03:49:23 am
15KW no way ! First off that antenna would be doing good to handle 5000 watts. A Texas Star "Hot Plate" is 1000 watts and about 12" L x 7" W x 5" H and has 2 fans. A "Hot Plate" needs at least a 130amp alternator to operate without dimming factory old fashion low beam headlights. How do I know ? South Mississippi out in the sticks where houses are 2 or 3 miles away and it doesnt interfere with anyone. A TS "Sweet Sixteen" is 1600 watts and about as big as you can put in a vehicle unless you have a diesel pickup with 2 or 3 high power alternators. I have been around a lot of amps over the years out in the country side. The largest I ever had was 750 watts and it dimmed my low beams with a 100 amp alternator that put out 100 amps at 1500 rpm. I used it on the road in west Texas 30 years ago from 8PM until I stopped to sleep at 4AM.

The foto is a Texas Star Sweet Sixteen 1600 watt. The 1000 watt "Hot Plate" looks the same.

Title: Re: Pickup Truck With Massive HAM Radio Antenna Clipping my Soun System!
Post by: Jared Bartimus on April 12, 2021, 09:00:48 pm
As far as i have been informed its legal to sell amps. You can buy them online, i have seen them in CB section in truck stops, a CB radio shop here in socal sells them. If they are still illegal the feds are not inforcing the law. In the 70's many CB radio guys in south mississippi had tall antennas in their yard with tube amps connected to their CB. I never knew of anyone to get busted.

It is probably technically legal to sell amps for any frequency range, just illegal to use them.  Some people like to claim it is actually for ham radio to keep out of trouble since they are similar frequencies.

Most legitimate ham radio operators are probably using 5W-100W radios in their vehicles.

15KW no way ! First off that antenna would be doing good to handle 5000 watts. A Texas Star "Hot Plate" is 1000 watts and about 12" L x 7" W x 5" H and has 2 fans. A "Hot Plate" needs at least a 130amp alternator to operate without dimming factory old fashion low beam headlights. How do I know ? South Mississippi out in the sticks where houses are 2 or 3 miles away and it doesnt interfere with anyone. A TS "Sweet Sixteen" is 1600 watts and about as big as you can put in a vehicle unless you have a diesel pickup with 2 or 3 high power alternators. I have been around a lot of amps over the years out in the country side. The largest I ever had was 750 watts and it dimmed my low beams with a 100 amp alternator that put out 100 amps at 1500 rpm. I used it on the road in west Texas 30 years ago from 8PM until I stopped to sleep at 4AM.

The foto is a Texas Star Sweet Sixteen 1600 watt. The 1000 watt "Hot Plate" looks the same.



A vehicle could potentially do 15KW ERP though with the right antenna.  I have my doubts they are using a high gain antenna but most CB antenna specs seem to be wattage, length and 'range'.  Not useful for such calculations and I don't care to dig that much for specs.