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Author Topic: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip  (Read 216 times)

WB9LUR

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"ODX" - 13566.5 kHz CW - 22 meter Part 15 beacon running only 5 mW - yes 5 milliwatts of transmitter power! Beacon is operated by ham station VA3ODX. 5 mW is only 1/200th of a single watt! 932 miles from my QTH.

Received at : 01:14 UTC APR 4 2022 / 9:14 PM US Eastern

Here's a 17 second YouTube clip:

https://www.youtube.com/watch?v=N4Guwrenk4I


QTH NE Florida, USA - RX Kenwood TS-590
ANT - ground mounted trap vertical / inverted L array over buried radial field

... de WB9LUR
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73, Randy / WB9LUR - http://www.CallingDX.com

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W7XTV

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #1 on: April 07, 2022, 11:28:01 AM »

Between 13.553 and 13.567 MHz, the maximum field strength is 15.848 mV/m at 30 meters, per 47 CFR 15.225.  That calculates to roughly 5 mW output into a dipole.  I take it Canada has the same rule in their regulations.

I wonder if anyone is doing FT8 or other digital modes in that spectrum?

https://www.ecfr.gov/current/title-47/chapter-I/subchapter-A/part-15/subpart-C/subject-group-ECFR2f2e5828339709e/section-15.225
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He speaks fluent PSK31, in FT8...  One QSO with him earns you 5BDXCC...  His Wouff Hong has two Wouffs... Hiram Percy Maxim called HIM "The Old Man..."  He is... The Most Interesting Ham In The World!

N6YWU

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #2 on: April 07, 2022, 07:07:59 PM »

I’ve transmitted WSPR on 20M by toggling a Raspberry Pi GPIO pin thru a low pass filter, and had the signal spotted on WSPRnet at distances of over 2k miles.  IIRC, that’s a transmit power of around 10 to 20 mW.  A 6 dB attenuator would drop that down to 5 mW. 

So would doing this on the 22M RFID segment be legal for unlicensed WSPR Tx?  For, say, something like school student projects?
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W7XTV

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #3 on: April 07, 2022, 07:21:16 PM »

I’ve transmitted WSPR on 20M by toggling a Raspberry Pi GPIO pin thru a low pass filter, and had the signal spotted on WSPRnet at distances of over 2k miles.  IIRC, that’s a transmit power of around 10 to 20 mW.  A 6 dB attenuator would drop that down to 5 mW. 

That should work fine, and that LPF is absolutely necessary.

Quote
So would doing this on the 22M RFID segment be legal for unlicensed WSPR Tx?  For, say, something like school student projects?

Absolutely, since the power would be 5 mW or less, and your signal doesn't go over the band edges of 13.553 and 13.567 kHz.  You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.
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He speaks fluent PSK31, in FT8...  One QSO with him earns you 5BDXCC...  His Wouff Hong has two Wouffs... Hiram Percy Maxim called HIM "The Old Man..."  He is... The Most Interesting Ham In The World!

W7XTV

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #4 on: April 08, 2022, 03:46:32 PM »

I'm hearing "PCO PCO PCO" then a 5-second carrier, repeated on 13.563 CW as I write this.  Very weak but definitely copyable.  Code speed is about 10 wpm or so.
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He speaks fluent PSK31, in FT8...  One QSO with him earns you 5BDXCC...  His Wouff Hong has two Wouffs... Hiram Percy Maxim called HIM "The Old Man..."  He is... The Most Interesting Ham In The World!

K3XR

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #5 on: April 08, 2022, 04:01:30 PM »

You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.

Just curious...Where that specific prohibition against using your call sign can be found.  I looked at the Part 15 link unless it may be in Part 97?
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W9IQ

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #6 on: April 08, 2022, 04:24:45 PM »

You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.

Just curious...Where that specific prohibition against using your call sign can be found.  I looked at the Part 15 link unless it may be in Part 97?

You could use your amateur radio call sign but it would be superfluous or extraneous as no call signs are required.

- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

K3XR

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #7 on: April 08, 2022, 04:36:59 PM »

You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.

Just curious...Where that specific prohibition against using your call sign can be found.  I looked at the Part 15 link unless it may be in Part 97?

You could use your amateur radio call sign but it would be superfluous or extraneous as no call signs are required.

- Glenn W9IQ
Thanks for your opinion.
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W9IQ

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #8 on: April 08, 2022, 04:49:53 PM »

Thanks for your opinion.
You are welcome.
- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

W7XTV

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #9 on: April 08, 2022, 05:05:56 PM »

You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.

Just curious...Where that specific prohibition against using your call sign can be found.  I looked at the Part 15 link unless it may be in Part 97?

I thought the FCC considered using your callsign outside the ham bands, even when using Part 15-legal power levels, illegal.
« Last Edit: April 08, 2022, 05:09:46 PM by WW7KE »
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He speaks fluent PSK31, in FT8...  One QSO with him earns you 5BDXCC...  His Wouff Hong has two Wouffs... Hiram Percy Maxim called HIM "The Old Man..."  He is... The Most Interesting Ham In The World!

W9IQ

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #10 on: April 08, 2022, 05:07:07 PM »

You can't use your ham call, of course, but anything else goes as long as it can't be confused with the callsign of a licensed station in any country.

Just curious...Where that specific prohibition against using your call sign can be found.  I looked at the Part 15 link unless it may be in Part 97?

I thought the FCC considered operating outside the ham bands, even when using Part 15-legal power levels, illegal.

If Part 15 has legal power levels, how can it be illegal?

- Glenn W9IQ
« Last Edit: April 08, 2022, 05:09:08 PM by W9IQ »
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

W9IQ

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #11 on: April 08, 2022, 05:33:23 PM »

I thought the FCC considered using your callsign outside the ham bands, even when using Part 15-legal power levels, illegal.

I see you edited your post since my last response.

Part 97 regulations define the right, privileges and limitations when you are transmitting as a ham radio operator.

When you are transmitting under Part 15, any limitations and rights of Part 97 do not apply unless specifically called out in Part 15. So unless Part 15 has specific ID requirements or effectively prohibits the use of ham call signs, then there is no issue. Under the low power provisions of Part 15, there are no ID requirements nor ID limitations. So using your ham radio call is not a problem from an FCC perspective.

- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

W7XTV

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #12 on: April 08, 2022, 07:38:01 PM »

I thought the FCC considered using your callsign outside the ham bands, even when using Part 15-legal power levels, illegal.

I see you edited your post since my last response.

Part 97 regulations define the right, privileges and limitations when you are transmitting as a ham radio operator.

When you are transmitting under Part 15, any limitations and rights of Part 97 do not apply unless specifically called out in Part 15. So unless Part 15 has specific ID requirements or effectively prohibits the use of ham call signs, then there is no issue. Under the low power provisions of Part 15, there are no ID requirements nor ID limitations. So using your ham radio call is not a problem from an FCC perspective.

- Glenn W9IQ

In any case, whether it's spelled out or not, I don't think it's a good idea to use my ham call outside the ham bands that my license class (Advanced) allows.  I wouldn't use it for Part 15 any more than I would use it in the Extra segments or on the CB band.

Since there aren't any specific callsign requirements for Part 15, it should be easy to come up with something else.  Why tempt fate?
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He speaks fluent PSK31, in FT8...  One QSO with him earns you 5BDXCC...  His Wouff Hong has two Wouffs... Hiram Percy Maxim called HIM "The Old Man..."  He is... The Most Interesting Ham In The World!

K3UIM

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Re: ODX Part 15 22 meter beacon - only 5 milliwatts - YouTube clip
« Reply #13 on: April 16, 2022, 07:10:37 AM »

I'm glad I can read 'fine print', Glenn. Woo-haw!!
Charlie
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Charlie. K3UIM
Where you are: I was!
Where I am: You will be!
So be nice to us old fogies!!
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