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paul1598419

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That remind me of a funny story that happened back when I was at Lamar University back in the early 1970s. I was working as a tech at the time and a customer was complaining his neighbor, a Ham radio operator, was transmitting on his TV, phone and everything else it could get into. Seems he was running a linear amplifier and was also chummy with the local FCC officer. He had it set up so he could switch the linear on or off at a moments notice and would always pass any investigation into his use of it. After weeks of getting nowhere, I suggested my customer take a straight pin and push it though the coaxial cable to the ham operators antenna. Problem solved. :crackup:
 



diachi

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That remind me of a funny story that happened back when I was at Lamar University back in the early 1970s. I was working as a tech at the time and a customer was complaining his neighbor, a Ham radio operator, was transmitting on his TV, phone and everything else it could get into. Seems he was running a linear amplifier and was also chummy with the local FCC officer. He had it set up so he could switch the linear on or off at a moments notice and would always pass any investigation into his use of it. After weeks of getting nowhere, I suggested my customer take a straight pin and push it though the coaxial cable to the ham operators antenna. Problem solved. :crackup:

Christ, that poor amplifier ... and the coax too I bet! :crackup:
 

paul1598419

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Christ, that poor amplifier ... and the coax too I bet! :crackup:

Yeah, IIRC we figured he was running a 1 kW linear amplifier at the time. I'd have loved to see those finals as he keyed his mike. :gun:
 

paul1598419

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This was in southeast Texas and the guy was a real a-hole. Tried many times to get him to comply and give his poor neighbor a break, but he insisted he was legal, even though we took a spectrum analyser to his neighbor's house and saw him splattering across many bands. I was still in my 20s and I would never give this information as a first response, but in this case....
 

Alaskan

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Maybe it wasn't a ham, but an illegal CB operator running power? The perceived interference, well, I guess it is regardless of whether he was out of band or not, but a properly designed linear amplifier won't put out harmonics and noise outside of the spectrum they use, within limits which are set by the FCC. However, if you live right next to them, the amount of power will get into speaker wires, into circuit boards, phone lines etc. while they are not doing anything illegal, their amplifier can be completely clean and transmitting where authorized, just that the transmitter and the individual being bothered by it live too close together. As a ham for the last 45 years myself, I'd hate to think someone would pin my coax and ruin my equipment in spite, but most responsible amateurs should and would take personal responsibility to fix the problem, if allowed. Maybe this guy was a jerk, if he was, I might pin that coax myself.
 

diachi

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Maybe it wasn't a ham, but an illegal CB operator running power? The perceived interference, well, I guess it is regardless of whether he was out of band or not, but a properly designed linear amplifier won't put out harmonics and noise outside of the spectrum they use, within limits which are set by the FCC. However, if you live right next to them, the amount of power will get into speaker wires, into circuit boards, phone lines etc. while they are not doing anything illegal, their amplifier can be completely clean and transmitting where authorized, just that the transmitter and the individual being bothered by it live too close together. As a ham for the last 45 years myself, I'd hate to think someone would pin my coax and ruin my equipment in spite, but most responsible amateurs should and would take personal responsibility to fix the problem, if allowed. Maybe this guy was a jerk, if he was, I might pin that coax myself.



If it was CB, he'd be breaking the law simply by running power (>4W for the US I think?).

But yeah, generally ham operators will be happy to resolve issues. Sometimes it's just cheap/poorly designed electronics that pick up on fairly powerful (but not necessarily above limits) transmissions. My mum has a touch lamp that'd turn on and off when keying up on 10m, and that was at fairly low powers, 20 or 30W.
 

paul1598419

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If it hasn't changed the power limit for citizens band radio is 5 watts. There was a craze going on back in 1975 where everyone had a CB radio. It was mass insanity. And, of course, because i had electronics experience had to install and set SWR on many units and antennae.
 

diachi

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So 3.6MW might be illegal then? :thinking: :crackup:


Yeah haha, even for hams, we get much larger limits, but not anything close to 3.6MW. (Which is PEP [Peak Envelope Power], not ERP. ERP [Effective Radiated Power] at HAARP is up to 4GW.)

In Canada (for advanced license holders) it's 1000W DC input to the anode/collector of the transmitter stage that provides RF to the antenna. OR 2,250W PEP for any type of single sideband emission OR 750W carrier power for any other type of transmission.

The US limit is 1500W for all modes.

I've only got the basic Canadian license so I'm allowed ~1/4 of the powers I mentioned above, 250W, 560W and 190W respectively. Which really, is plenty.
 
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CurtisOliver

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Interesting. You are allowed quite a lot of power on a basic license then. :)

Anyway, if I get caught I will just say that I was only a tiny bit over the limit. :D It just perspective! :whistle:
 
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dubious speculation

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What could I possibly use 40 high drain Samsung 25R 18650's for :eek:

20170501_2022352_zpsa9wfygvc.jpg


20170501_2022192_zpsqcddfrsu.jpg


Build thread coming soon ;)
 




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