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ArkyBeagle t1_j6dwwdj wrote

You're correct - it cannot see ATSC 3. I somehow missed that that was a constraint here. Oops!

I'm in flyover country so ATSC 3 hasn't made it here.

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wkomorow t1_j6e0oqe wrote

No problem, it might have been a good replacement for my recast. They just have the big 4 and PBS on a single frequency here using ATSC 3. I would benefit from ATSC 3 now because the ATSC 3 is on rf 22, and one of my networks is on rf 7 (ATSC), which has too much interference on it. I appreciate the response.

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ArkyBeagle t1_j6e3hi1 wrote

> which has too much interference on it.

Edit: I'm being very literal about "interference" here but hopefully, the other pathologies are spelled out.

That doesn't sound right. That should be licensed bandwidth. I can easily see simply R squared loss or multipath being a problem ( multipath rejection being the one killer feature of 3.0 ) but if anybody's emitting on that band, I'd bet the FCC would like to know.

They'll take it less seriously than HF/UHF interference on aviation comms of course.

Then again, 7 is at the edge of a band plan.

https://www.fcc.gov/enforcement/areas/interference-resolution

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wkomorow t1_j6e6w6p wrote

The FCC does know. They are the ones that told me solar inverters are except from section 15 part b of their regs. We have suppression and shielding and cancellation on the inverters and the antenna. Engineers have been out. The only solution that would work is ground install of the antenna, because the issue is localized to the roof. I would lose several stations in a ground install, we did several tests. The only solution is replace all 24 inverters. Not worth it given I mostly watch TV at night, when there is no interference.

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ArkyBeagle t1_j6e8al7 wrote

> They are the ones that told me solar inverters are except from section 15 part b of their regs.

Gaaah! Well, poot then.

> The only solution is replace all 24 inverters.

You are a very thorough human being :)

So being a nerd, I gotta ask - those were NOT granted Part B but because green, they're exempted? I honestly thought everything ever made had to have Part B.

I'd lean on the solar panel vendors to put a grounded Faraday cage on the inverters. At their expense. I'm also wondering why an inverter is emitting in that band... That's pretty high up in frequency for an inverter. Is it a square wave inverter? This is very clearly a design defect.

My experience is that requests like that on legal stationery/letterhead get more attention.... lawyers love doing that sort of thing for you. Especially since there's clearly a tort; FCC regs do not constitute a fully legally binding exemption. Er, they used to not anyway. You're one guy and I imagine the solar panel people have more than one customer...

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wkomorow t1_j6e9nmy wrote

I am in a iffy reception area (valley surrounded by mountains) with traditionally very heavy cable penetration, so very few antennas around. No one around me has an antenna, which makes giving directions easy - look for the house with an antenna. My inververters are 10 years old and they convert dc to ac at the panel. The newer converters use a better shielding. It is more of an annoyance than a problem.

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ArkyBeagle t1_j6eat0p wrote

I've been on teams that had to get Part B before. Makes me grumpy about it :)

I still feel like the vendor has some measure of liability here. Part B isn't the same level as an electrical hazard but I'd at least try to get a healthy discount on upgraded converters. Find out the depreciation schedule for them , blah blah blah.

Any rate, an interesting issue and thanks for it.

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