Curious if the move to BPL transmission, as it IS moving forward, will affect any of SSPI's customers. From another thread I follow regarding voice recognition technology, one of their subsidiaries will begin broadband over power line transmission. It holds great potential for areas where cable and DSL may never go. This interference makes perfect sense to me but was an eye opener at the same time. Interesting more then anything else. fwiw. Any comments welcome.
hands-free, re: BPL
You must be quite knowledgeable about RFI. To refresh your memory ... Power lines have been used for years to carry intercoms and 'in-house' radio stations, by sending AF over the lines, which were decoded by a special receiver; these added carriers were filtered out by powerline transformers. I know of a college way back in 1966 that had one such station, so the theory, practice, and technology are hardly new or cutting edge.
As you are well aware, data throughput are limited by frequency used. AF of 100Hz-16K Hz carry voice and music of fairly low fidelity, but when you crank up the frequency to HF-low VHF range, a grundle more data - whether analog music or digital bits - becomes possible. BPL operates in the HF range, ie., from just above the AM broadcast band to mebbe 50mHz.
The BPL industry wants to use these frequencies as unlicensed users under Part 15 of the FCC rules, meaning that the user (BPL and you) must guarantee that your use will not affect licensed users of the frequencies,. Part 15 users must accept any interference from licensed users.
Here is the problem: above ground power transmission lines are what? How about real, real long antennas. Unless transmission lines, connections, transformers, etc., are technically perfect, properly grounded, isolated, etc. AND REMAIN THAT WAY, they WILL radiate the primary frequency and harmonics. They also will receive these frequencies, but that is not my problem as you are Part 15.
Now, no nodding, ... these emissions will affect licensed users: the amateur service, airlines (who use HF on all but local transmissions), Homeland Security, the military, the business bands .... there are a lot of 'em.
On to your specific comments ....
'I predict that not only will BPL become universal,'
Whether I like it or not, this may be so ... the present administration has shown a capability for ignoring all facts it finds inconvenient, and glomming on to a single mis-represented fact as the entire truth.
'but that I'll be able to co-exist with it'
You can co-exist until there is an in-flight emergency on your airline flight and effective comm cannot be established because of BPL RFI. Or, until there is a local/regional /national emergency (manmade or natural) which needs long-haul radio transmissions. As cell phone and 800mHz trunked systems, whatever, cannot provide enough comm for emergency response, the fallback is HF - but can it, with BPL RFI? (Note: I wouldn't guarantee SATCOMM would be available).
'and not have to wear a tinfoil helmet to deflect the radio-carcino- techno-weirdo ruminations of twenty first
century Chicken Littles.'
To my knowledge, this has not been a complaint about BPL, except of course, that ALL RF sources must meet the provisions of OET Bulletin 65-you likely have a copy at hand to verify these requirements. BTW, your comments seem to imply there are no legitimate concerns about BPL deployment.
'Quiet !'
Yes, try that, unless you know what you are speaking of.
I think the toaster is listening.
Unless you are Winston Smith, I don’t think that is a problem.
It isn’t very likely you have read this far, but it was fun for me to write. |
