Tag Archives: SDR

Sights From Field Day 2017

Field Day 2017 is but a memory for us now. Dave, K1DLM, our Field Day Chairman, and the entire Field Day team did a great job with putting together our Field Day operation this year.

We are still adding up our score and collecting pictures and video from everyone. I wanted to get something out quickly so that we could begin to enjoy some of the memories. So here is my quick Sights from Field Day 2017….

Field Day 2017 Telegraph Article
Our Field Day Telegraph Article

We did a fantastic job on publicity this year…

Field Day 2017 - Parking Lot Was Full
The Parking Lot Was Full

and the parking lot was full of visitors and members on Saturday and Sunday.

Field Day 2017 Public Info Tent Was A Hit
Our Public Info Tent Is A Hit

Our updated Public Information Tent was a hot spot for our many visitors (over 45 visitors signed our guest register)!

Field day 2017 Visitors - ARRL Section Leaders - Peter, K1PJS And John, K1UAF
ARRL Section Leaders – Peter, K1PJS And John, K1UAF

The ARRL “brass” came out early to congratulate Dave, K1DLM our Field Day Chairman, and to tour our site.

Field day 2017 Food Was Awesome!
The Food Was Awesome!

The food was unbelievably good – thanks, Valerie!!! And the N1FD cafe’ was a hot-spot as usual.

Field Day 2017 Site Setup On The Upper Field
Site Setup On The Upper Field

Site setup at Hollis-Brookline High School began with the 40M V-Beam.

Field Day 2017 Site Setup On The Upper Field - The 60 Ft Tower Coming Together
Site Setup On The Upper Field – The 60 Ft Tower Coming Together

The tower team began on the lower field by setting up the new 60 ft. tower.

Field Day 2017 - The V-Beam Was Back
The V-Beam Was Back

The 40M V-beam was awesome as ever and went up in record time…

Field Day 2017 - A New 60 Ft Tower
New 60 Ft Tower

and our new 60 ft. tower was a sight to behold!

Field Day 2017 - 40M SSB Station
40M SSB Station

We built lots of stations – 3 SSB, 3 CW, a RTTY/PSK Digital Station, a GOTA station, a 6M Station with a new yagi, and a computer controller Satellite Station. We also setup a 2M/70cm Go Kit for talk-in and APRS demos. All totaled, we had 10 transmitters on the air! Our exchange was 7A NH.

Field Day 2017 Solar Power Setup
Solar Power Setup

We got our Solar-Battery bonus late on Saturday.

Field Day 2017 - Brian, AB1ZO Operating SSB
Brian, AB1ZO Operating SSB

Everyone operated very hard and we made more contacts than last year!

Field Day 2017 CW Ops - Dennis, K1LGQ
CW Ops – Dennis, K1LGQ

Our CW operators were amazing again this year. Here’s Dennis banging out CW QSOs. Dave, KM3T even operated SO2R for a period – calling “CQ” and working contacts on both 20M and 40M CW at the same time! Gene, W3UA brought his CW skimmer and we set up an OCF dipole to provide on-site CW spots.

Field Day 2017 - And The Generators Played On...
And The Generators Played On…

And the new generators worked flawlessly and were much easier to service.

Field Day 2017 - Curtis, N1CMD Making Satellite Fun!
Curtis, N1CMD Making Satellite Fun!

Curtis, N1CMD ran our Satellite Station 2.0 and wowed everyone while making satellite contacts….

Field Day 2017 Satellite Station 20 In Action
Satellite Station 2.0 In Action

and our visitors got a kick out of seeing the computer controlled satellite antennas.

Team Finchum In Action
Team Finchum In Action

Team Finchum was in high gear as always – here’s Abby, AB1BY operating with her brother Connor, KC1GGX. It seemed like Abby was on every SSB station that I looked at all weekend long…

New Digital Station For Field Day 2017
New Digital Station For 2017

Our new SDR powered Digital Station worked well and we had lots of digital contacts using the antennas on the new 60 ft. tower.

Field Day 2017 SDR GOTA Was Cool!
The SDR GOTA Was Cool!

The SDR-based GOTA station worked out super well. Ira, KC1EMJ was our GOTA coach and was busy on Saturday and Sunday introducing our guests and newly licensed members to “high-tech” Amateur Radio. We had many young people try Amateur Radio for the very first time on our GOTA station.

Field Day 2017 Remote SDR System
Remote SDR System

We operated the two SDRs for the Digital and GOTA stations remotely over a coax cable data link between the upper and lower fields. Pierce, K1FOP and Dave, K1DLM put together this high-tech setup and the underpinning data networking system.

Field Day 2017 - John, W1SMN and Desmond, WK1V Operating SSB
John, W1SMN, and Desmond, WK1V Operating SSB

Did I mention that we operated hard making lots of QSOs?…

Field Day 2017 Drone Sighting
Drone Sighting

There were Drone sighting all weekend long…

and Desmond, WK1V got some amazing video from the air.

It was a lot of fun operating as N1FD, 7A NH!

Anita, AB1QB, our scoring chairman is still working on tallying up our score but it will be higher than last year.

Please take a minute and send me any photos or video that you have from Field Day 2017. We’ll be producing a video of all of the fun for the Field Day 2017 Recap at our club meeting on July 11th. Don’t miss it!

Fred, AB1OC

Hashtags: #ARRLFD #N1FD

The Day I Sold My HF Radios by Michael KG9DW

This article is from the March 2017 Amateur Radio Weekly.

The day I sold my HF radios by Michael KG9DW

15 March 2017 | by Michael KG9DW

Yesterday I sold all of my HF radios. At this moment, I have zero radios capable of transmitting below 2 meters. It started off because of an advertisement in QST, and then a visit to AC9S to see his Flex 6700. I became obsessed with SDR, reading everything I could and watching YouTube videos of hams around the world. I had to have a panadapter…wait, I need 4 panadapters!

I settled down a bit and got busy with other hobbies for a couple of weeks. A few contacts on PSK31 and CW, and I was back to being hot and heavy on a new radio – and one with all the whiz bang features. So on Friday, I emailed Flex Radio with a list of my current HF rigs. Matt got back with me Monday morning with a quote for trading them in that wasn’t too far off the used market value. Well rats…time to get serious or drop this fantasy.

A little back and forth, and then a search of the online swap meets led me to list my radios for sale online Monday night. By Tuesday morning they all were sold! Yikes! I ended up getting 25% more than the trade-in offer by selling myself, even when I took shipping and PayPal fees into account. So Tuesday afternoon while at the gym I took a break and called up Matt at Flex. I placed my order, and a new rig will be headed my way in the coming days. My old radios went out by UPS this afternoon. I’m currently a VHF/UHF only ham!

I’m hearing of hams that are giving up on HF, or even ham radio entirely due to the band conditions. Not me…I’m doubling down on this hobby by consolidating my HF capabilities into a Flex. I’ll let you know how that works out!

SDR Interface

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

Layne, AE1N

A Good Day To Be Doing Radio

It’s snowing at my QTH. A lot. If your QTH is within 30 miles of mine, then it’s bad for you too. Normally, I don’t mind the snow blowing. But in this instance it’s not supposed to taper off until 11 pm — meaning I…you…we…us — will likely have to go outside multiple times just to keep pace with it. Additionally, not only am I doing the driveway but the decks and sunroom roof. On days like this, I look forward to the days of being too old for it to be considered unreasonable for me to do it myself. For now, I am cursed with youth. Damn youth. So while I await my impending fate, I decided to get some fun stuff done. If you have some time, I’ve enumerated three projects I’ve been working on. Get some coffee, and enjoy!

Project 1:

The first item on my list for a while is to get my ADS-B (Automatic Dependent Surveillance Broadcast) receiver going. For those of you unfamiliar with this, I won’t delve too deeply into it, but I’ll try to provide useful information. ADS-B / Mode S is data transmitted on 1090 MHz, which is downlinked from airborne platforms communicating their telemetry such as latitude, longitude, altitude, speed, heading, ICAO number, and flight numbers (as long as they have an ADS-B transmitter on board, which most do). If you’re familiar with the website FlightAware, users who collect their own ADS-B data, can create an account with FlightAware and upload their data to feed the system helping to provide a robust and complete air-picture. There are references and links all over the web on how to achieve this, so I won’t enumerate them here but know they are out there and an easy Google search away.

To intercept these signals/broadcasts, one needs a receiver and an antenna. Of course. The receiver is easy. I bought an RTL-SDR dongle (which I saw someone brought in during the Xmas Yankee Swap — AWESOME gift) which came with two stock antennas all for $24.95. This software-defined radio is a neat little gadget. I also download the RTL-SDR library package and GnuRadio in order to actually play around with its functionality. The dongle comes with an SMA connector, so to attach any coax, you’ll need an SMA-male to an F-female connector. (Aside: The other Sunday, I intercepted some broadcast radio stations and was able to demodulate them. The structure of the signal looked just like that from the Wikipedia article about FM transmissions!! The one down side about these dongles, however, is that the lowest frequency they can reach is 24 MHz, which isn’t great for HF work. I was hoping to intercept my own transmissions from the shack, but no dice on this.)

Ham Radio Projects - RTL-SDR dongle
RTL-SDR dongle

The next bit was the antenna. Since ADS-B signals are vertically polarized, one has to of course use vertical antennas. I tried two different designs for this. The first was a colinear coaxial antenna whose plans you can view from the link. I did this a while back and found it a bit cumbersome, additionally, I wasn’t able to collect a ton of data. Many others using this antenna’s praises and I think the fault is the author for not correctly constructing it.

I then found another inexpensive design called the cantenna. This was by far the easiest of the constructions.

Ham Radio Projects - A Cantenna

The theory behind it was that one would take a quarter-wavelength piece of bare copper wire (from inside a spare coax lying around) which at 1090 MHz is about 69mm, and then the cutoff part of a soda can would act as the ground-plane (completing the other quarter-wavelength of the antenna). As seen from the picture, there is an F-female to an F-female connector which connects the bare copper wire to RG-6 coax cable (which is running through the PVC in the picture). And because the RG-6 was only $6.99 at Home Depot, I picked up 15 ft. for use with this antenna. You probably do not want to use coax much longer than this (and ideally shorter is better) at these frequencies due to losses in the coax.

Lastly, was to get the right software. There are a ton of software options. My ultimate goal is to run this on a RaspberryPi, setup somewhere outside, where I can open up a TCP port and pipe the data through so I can look at it from any machine connected to my LAN. To this end, I found the dump1090 distribution was an excellent choice. This dude wrote some excellent code, well-commented, and compiled in a jiffy.

With everything in place, I let her rip and began to integrate data. After about an hour, on Sunday evening, I was able to get the following results (after post-processing the data in MATLAB — eventually I’ll move this over to Python to run on the RPi)

ADS-B Flights above my QTH
ADS-B Flights above my QTH

The legend is as follows: The blue square is my QTH. The upper right square is the Lawrence Municipal Airport in North Andover, MA while the lower right square is Logan Airport. Everything else is color-coded by flight number. Even after an hour, I was able to get quite a few hits. Though not shown in this image, the farthest I’ve been able to see is 78 nmi! I’m going for the horizon limit folks!!

Project 2:

Get on the radio! Oh, man, have I been looking forward to this. Ok, so part of this is my fault. My shack isn’t complete yet. I do not have a great system of running my feed lines into my home. That’s for the Spring. For now, I have to open and close my basement window and pull the coax through. It kind of sucks. But, nevertheless, only temporary.

Other excuses: work is long and arduous now, need to hang out with my W1FEY (that’s my wife’s unofficial call-sign — I like to think I’m clever), and been doing a lot of work for the club in the form of bringing you rock-solid programming and figuring out the High-Altitude Balloon project.

Now that the excuses have been enumerated and judged, it’s time to put them aside and do some operating. I love trying to work DX. I’m not great at it, but I’m learning. Plus, every time I hop on the ol’ ICOM-7300, I have an excuse to learn how to use DXLab a little better. In fact today, I fired up the SpotCollector for the first time. I’m no expert, but I’m vectored the right way 🙂

I found that 17 and 20m worked out particularly well today. 40m was good, but I didn’t work anyone on there, and 80m was pure static during the late morning or early afternoon. (Maybe that’s just me). I only got to make 4 QSO’s but that’s 4 more than I had this morning ladies and gentlemen. They were:

I was going to work more, but then W1FEY CQ’d for me in the shack and told me to look outside. When I did, it was about time to suit up.

Project 3:

Before braving the elements, however, I wanted to use an antenna analyzer to check out my SWR’s for my Buckmaster 7-band OCF dipole. I love this antenna. I had decided that the 3 kW version was right for me since at some point I wanted to add an amp. And I did…inherited an Ameritron AL-80B from a friend’s dad who is a Silent Key.

Anyway, I noticed that 6 and 10m were conspicuously bad. As a result, I had asked Greg (W1TEN) if I could borrow his analyzer. Being the gracious gentlemen that he is, he loaned me his RigExpert AA-54. Really neat gadget and the cool thing (maybe this is standard but it was cool for me) is that with a simple USB connection, one can get results on your machine and save data for later use.

In the next set of pics, I’ll show my results for the 7 bands that the Buckmaster covers: 80, 40, 20, 17, 12, 10, 6: (It might be a bit hard to see)

80m SWR values
80m SWR values
40m SWR values
40m SWR values
20m SWR values
20m SWR values
17m SWR values
17m SWR values
12m SWR values
12m SWR values
10m SWR values
10m SWR values
6m SWR values
6m SWR values

What’s immediately obvious is that 10m is beginning to get wonky and 6m is completely gone. At least this begins to explain why I can’t hear anything on these bands. I did a bit of research online asking if anyone else encountered the same issues and some people seem to suggest that there will be a few bands that your SWR will not be ideal. With that said, however, it does seem most people have fantastic luck with these particular antennas, and so it could be user error. Perhaps something when I initially put it up? But if you’ve read this far, then maybe you have some suggestions for me…


Well, thanks for reading. I hope you enjoyed a break from the snow and my somewhat lively banter kept you mildly entertained. Any comments, concerns, and questions welcomed.

Brian, AB1ZO