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Another new source of RFI on 70CM

Jan 29th 2012, 20:26

K8WHB

Joined: Jan 11th 2011, 19:02
Total Topics: 0
Total Posts: 0
Well it looks like the FCC has done it to us again, this time on 70CM. Friday (1/27) Federal Register published the rules for MedRadio devices using segments of the 70CM band.

I read the entire piece and found a couple of interesting items. First, even though they are unlicensed devices, the MedRadio implant devices are given full secondary status, the same status amateur radio has in the 70CM band. Now interestingly, read 95.1211 (c) of those new rules and it says MedRadio devices must cause no harmful interference to and and must accept any interference from, to quote "from authorized stations operating in the 413-419, 426-432, 438-444 and 451-457 MHz bands". Ahhh, but there is more! Read on to 95.1215 (b) & 95.1217 (b) on the disclosure statements & labeling requirements, and the word PRIMARY is added. So it appears we have a conflict here. One place says hams are covered (since we are specifically authorized by license to use 12 MHz of this spectrum {except above "Line A", where we are only allocated 8 MHz}) and the other says we're out in the cold (since hams are not primary users {we got shafted out of our primary status by the DOD and the FCC back in the 1970s}).

The medical people will read the paperwork included with the devices and probably never read 95.1211 (c), so it appears, as far as the meddical community is concerned, we will be stuck having to tolerate any interference we get from these devices AND be left out in the cold if a ham causes interference with one of these devices.

Makes one wonder if the folks at the FCC read this stuff before they send it on to the Superintendent of Documents?
Feb 6th 2012, 03:11

KJ6SBW

Joined: Dec 12th 2011, 14:43
Total Topics: 0
Total Posts: 0
The medical devices are very limited in power, so I would guess that unless you had a neighbor with one (or more) of these devices, you wouldn't be bothered.

I'm more concerned about a 100 watt repeater causing harmful interference with one of these devices or at a hospital. Or, perhaps a transmitter in a home with a neighbor next door with a device.
Feb 7th 2012, 07:51

KB0HAE

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I too am more concerned with these devices being interfered with by the presence of strong signals. I hope that these devices are designed to reject interfering signals.
Jun 5th 2012, 04:33

KH2G

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I would not think these devices are part of a life support system so interference with them will be more of a nuisance factor to them as they to us.If they are a part of a life support system, it was ridiculous to design it around these freqs. Understood spectrum is getting tighter and tighter.
Jun 18th 2012, 05:24

KM3F

Joined: Mar 6th 2008, 13:50
Total Topics: 0
Total Posts: 0
If you search for' Medical Implants on the 450 Radar Band', it will answer all your questions.
1. The device is close range operated.
2. There are a number of channels it wiil search in the presents of interference. If none is found it shuts down.
3. The device has digital addressing that an analog signal is unlikely to have no effect on.
Read the whole paper so this is all understood.
There is to much guessing going on.
Read the facts.
Good luck.

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