Posts Tagged ‘QRPp’

On this day, 48 years ago


Here men from the planet Earth 
First set foot upon the Moon
July 1969, A.D.
We came in peace for all mankind

Neil  A. Armstrong     Michael Collins     Edwin E. Aldrin Jr.
Astronaut                Astronaut                  Astronaut

Richard M. Nixon
President, United States of America

To read about the communications systems that the Lunar Module employed, here are two good links from the NASA Archives: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720023255.pdf and https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090015392.pdf

The S-band transceiver was the primary transceiver used for TV, telemetry, biomedical data, and voice communications from the Lunar surface. It had an output power of  750 mW (QRPp!).  That signal then went to the S-band power amplifier, which boosted the signal to an outstanding "QRO" signal of 18.6 Watts.

72 de Larry W2LJ
QRP - When you care to send the very least

On this day, 48 years ago


Here men from the planet Earth 
First set foot upon the Moon
July 1969, A.D.
We came in peace for all mankind

Neil  A. Armstrong     Michael Collins     Edwin E. Aldrin Jr.
Astronaut                Astronaut                  Astronaut

Richard M. Nixon
President, United States of America

To read about the communications systems that the Lunar Module employed, here are two good links from the NASA Archives: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720023255.pdf and https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090015392.pdf

The S-band transceiver was the primary transceiver used for TV, telemetry, biomedical data, and voice communications from the Lunar surface. It had an output power of  750 mW (QRPp!).  That signal then went to the S-band power amplifier, which boosted the signal to an outstanding "QRO" signal of 18.6 Watts.

72 de Larry W2LJ
QRP - When you care to send the very least

A fast cool trip to the park

Starting out on my cool walk
CHA P-Loop antenna
I had the day off work today and it looked very nice outside, the sky was clear and the sun was out. I wanted to take this opportunity to test out my new portable antenna. I packed up my Elecraft KX3, batteries, key and my new Chameleon CHA P-Loop antenna. This post is not a review of the new antenna before I do that I want to try out the antenna several times. Before heading out I did not check the propagation reports, I find if I do this and they are poor it casts a shadow over the outing.As I was saying the day from inside the house looked nice but once out there was a cold wind off the lake, it felt like a cool fall day and not spring. Anyway.....because of the poor weather, my lack of warm clothing I quickly setup the antenna, checked out how it tuned on 10, 15, 20 and 30m and gave a few CW CQ's. With no answers and the wind picking up I was satisfied the antenna at least worked.
My setup 

A fast cool trip to the park

Starting out on my cool walk
CHA P-Loop antenna
I had the day off work today and it looked very nice outside, the sky was clear and the sun was out. I wanted to take this opportunity to test out my new portable antenna. I packed up my Elecraft KX3, batteries, key and my new Chameleon CHA P-Loop antenna. This post is not a review of the new antenna before I do that I want to try out the antenna several times. Before heading out I did not check the propagation reports, I find if I do this and they are poor it casts a shadow over the outing.As I was saying the day from inside the house looked nice but once out there was a cold wind off the lake, it felt like a cool fall day and not spring. Anyway.....because of the poor weather, my lack of warm clothing I quickly setup the antenna, checked out how it tuned on 10, 15, 20 and 30m and gave a few CW CQ's. With no answers and the wind picking up I was satisfied the antenna at least worked.
My setup 

A 40m WSPR weekend

40m from 7am-7pm local time
With the Solar cycle heading on a downward trend I have been reading how 40, 80 and 160m may be the bands of choice for QSO's. Since my MFJ 1788 will only venture down to 40m and at the best of times I have found it to preform like a wet noodle on this band. I decided this weekend to give WSPR a go on 40m using 1 watt to see what results I got. My 1 watt signal was picked up throughout Canada and the U.S. There was a one off to Spain but the consensus from WSRP.net was on 40m my DX was going to be North America. There was one odd report which repeated itself over and over, it was from WY1R saying he was hearing me on 6m?? Not to sure what that was all about. I also was checking with PSK reporter looking at WSPR mode and funny thing was there was never any hits for my call?
40m from 7am-1am local time

A 40m WSPR weekend

40m from 7am-7pm local time
With the Solar cycle heading on a downward trend I have been reading how 40, 80 and 160m may be the bands of choice for QSO's. Since my MFJ 1788 will only venture down to 40m and at the best of times I have found it to preform like a wet noodle on this band. I decided this weekend to give WSPR a go on 40m using 1 watt to see what results I got. My 1 watt signal was picked up throughout Canada and the U.S. There was a one off to Spain but the consensus from WSRP.net was on 40m my DX was going to be North America. There was one odd report which repeated itself over and over, it was from WY1R saying he was hearing me on 6m?? Not to sure what that was all about. I also was checking with PSK reporter looking at WSPR mode and funny thing was there was never any hits for my call?
40m from 7am-1am local time

100mW’s of raw power!!

The other evening I was having a cup of tea and checking out my new QST that just arrived and found myself very interested in a piece written by Steve Ford in his column Eclectic Technology. The title caught my eye "When a signal is barely a WSPR" Steve looked at how the Raspberry Pi could be used for WSPR transmissions. Seeing I have the Raspberry Pi3 this sparked my interest. It was pointed out that all you need to turn your Pi into a WSPR transmitter is a board from TAPR called QRPi.  The board is offered at a very reasonable price of 29.00 U.S and it's set for 20m at 100mW. Before I got to excited about this little project  I wanted to see if using 100mW's would net me any results. I have seen other hams in the past net great results with far less than 100mW's and WSPR is known for it's great decode at very low power........BUT.......I do have a challenging setup here. On Friday late afternoon I gave WSPR a go on 20m at 100mW and was I impressed with the results. I was received by DK6UG for a distance of 39383 miles per watt and also ON7KO for a distance of 37285 miles per watt. I was amazed that my setup was able to produce those results! Now another question I wanted to consider is at 100mW how much of that actual power makes it to my antenna? To do this I referred to a coax calculator I punched in the type of coax (RG8X) the SWR (1.4:1) the length (30 feet)  the frequency (14) and finally the power (100mW) The calculated amount I was informed was 92mW of raw power! So this bumped my miles per watt to 42810 for DK6UG and 4053 for ON7KO! It's not timo look more into the TAPR project!!

Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter

 
We never share your e-mail address.

Please support our generous sponsors who make AmateurRadio.com possible:

KB3IFH QSL Cards

Hip Ham Shirts

Georgia Copper

Ham-Cram
Expert Linears

morseDX

Ni4L Antennas

N3ZN Keys

West Mountain
R&L Electronics


Do you like to write?
Interesting project to share?
Helpful tips and ideas for other hams?

Submit an article and we will review it for publication on AmateurRadio.com!

Have a ham radio product or service?
Consider advertising on our site.

Are you a reporter covering ham radio?
Find ham radio experts for your story.

How to Set Up a Ham Radio Blog
Get started in less than 15 minutes!


  • Matt W1MST, Managing Editor




Sign up for our free
Amateur Radio Newsletter

Enter your e-mail address: