Re: Topband: problems with RFID-key-cards / transponder door locks in Hotels ?

[GeorgeWallner]

Tom,

The technology you are talking about is called NFC, Near 
Field Communications. It uses the magnetic (H) part of the 
RF radiation -- near field -- but it does have an electric 
component, although that is quite weak. The antenna, both 
in the lock and in the card, is usually a multi-turn loop. 
The lock transmits power which is picked up by the card's 
antenna and is used for powering the chip and 
communications. Most systems use a rolling code, which 
provides security and protection against interference.


It is not likely that your transmissions (even on 14 MHz) 
will trick the locks to open. It is more likely that 
during transmissions locks may not open, or open 
sluggishly. You may also get some noise on 20 meters from 
the side-bands of 13.56 MHz signal.


NFC readers will in the near future be used for point of 
sale card payments (contact-less cards) and will be 
installed at millions of merchant locations. They may turn 
into another source of noise on HF.


73, George

_
Topband Reflector

Re: Topband: Price of Copper Going Up

[Bruce]

Had a similar one and junked it out. Could have been from a BC-610 
transmitter. Somewhat  less than half of the weight was copper. The primary 
winding wire was not round, but about 1/4 inch square. (Big  heavy) The 
secondary wire is still in service as radials here in Belfast, Maine.  Take 
care not to injure your back when lifting

73
Bruce-K1FZ

Just curious, do you have any idea how much copper would be in a big old 
WW II plate xfmr that weighs 107 lbs?


Any guess?

Rick  K2XT 


_
Topband Reflector

Topband: Have you filed comments to FCC's proposed changes to 1900-2000 kHz yet?

[Anthony Scandurra]

This is a rewrite of Don Chester's excellent posting he made to the
Top Band reflector.  It contains simplified instructions for filing
you own comments.  Thank you, Don, for reminding us all about this!!!

The deadline is the 25th of this month.  Just 16 more days left!

Even if you have zero interest on what goes on in the top half of our
160 Meter band, its still crucial to get this passed.  In the unlikely
event that radio location beacons will ever return, it would impact
all users of the band, with everyone trying to squeeze into the bottom
100 KHz. This may be our only window of opportunity to regain primary
status across the entire band.

Here's how to file online.  It's really easy!

Click on this link:

http://apps.fcc.gov/ecfs/proceeding/view?name=12-338

You can view the comments others have filed by clicking on the blue
circle with an i in it in the column on the left labelled Recent
Public Filings.  If you need ideas about what to write, you can get
them from filings made by other hams.

To submit your own filing, write a letter of your own in a word
processor like WordPad (comes with every version of Windows since the
early 90s), Microsoft Word, OpenOffice, or AbiWord.  If your word
processor supports it, save it in PDF format (Word, AbiWord and
OpenOffice all do).

Then, go to this link:

http://apps.fcc.gov/ecfs/upload/begin?procName=12-338filedFrom=E

Fill out all of the required fields (the ones with red asterisks next
to them - there are only five).  You can leave all the other fields
blank. Attach your document using the Choose File button at the
bottom.

Let's not give the FCC the impression that few hams care about
maintaining and preserving Top Band.

73, Tony K4QE
_
Topband Reflector