Seeing IS NOT Hearing – Satellite SDR use on the rise

I happen to be a fan of using Software Defined Radio (SDR) to receive amateur satellites. It is an inexpensive way to view all the signals appearing on a satellite’s passband simultaneously.  While I don’t normally run SDR full time at my station, from time to time I use it to monitor activity on busy satellite passes because I can view and record all activity.

As a result of more people using SDR on satellites, I have discovered an operating trait that warrants discussion and evaluation.

On more than one occasion, I have given a call to a very specific station, and instead of my intended target had another SDR-based station appear on frequency immediately saying “QRZ? QRZ?” rather than wait and listen to who is calling on the frequency before transmitting. The SDR user saw a signal on their waterfall and clicked on it. They “pounced” on what they perceived to be another station looking to make contact which might not necessarily be the case.

I’ve see the same thing happen a few times with pileups.  There is an existing pileup in progress when the SDR station comes into the footprint. Rather than wait a short period to listen, they click on the new signal in their waterfall, and immediately proceed to “QRZ” on the frequency of the pileup, sometimes interrupting the flow of existing contacts.

Just today I heard this scenario: Station 1 calls CQ.  Station 2 went to answer. The SDR user clicked on the waterfall, heard only part of the callsign of Station 2, and proceeded to call Station 2, ignoring the possibility that Station 2 was attempting to QSO with someone else.

It seems to me the visual nature of SDR waterfalls is causing a temporary lapse in judgement when it comes to a basic ham radio principle that we apply to satellite operating — listen with our ears before transmitting.

SDR is a great listening tool. With great power comes great responsibility.

Revisiting Twitter & How to effectively use it for a satellite operation

In November 2014, I did a posting about using Twitter to advertise grid operations.  I suggest reading it before continuing with this post.

Now that a couple of years have passed, I’m glad to see more and more operators are moving towards using the platform.  I am a fan of it because it can be completely open and transparent.  Being cross-platform with many user options makes it a very flexible tool.  I’ve decided to post a few observations here as a follow-up to my original posting.

On privatizing your feeds…(protecting Tweets)
A few operators insist on making their Twitter feeds private. I’m not sure it really has any benefit other than perhaps reducing a small amount of “junk followers.”  I can understand their intentions are good but if your feed is private, it makes a lot of public-facing conversations seem awkward. If you have any “secret” information to offer, you really shouldn’t be putting it on Twitter (social media.)

Long conversations
One thing that can be annoying is long Twitter threads with 5 people trying to have a group conversation.  Sometimes these long threads become hard to follow.  Picture yourself an “outsider” to what is being discussed and see if it makes sense.  Probably won’t.  I’m guilty of this but try to stay out of long-winded replies.  Take it to a group “Direct Message” or private email if it gets to be a long discussion.  Just think about it before you “chime in.”  There are, of course, always fun exceptions (this one turned into an epic thread.)

Other options, revisited…
I’m a big fan of advertising operations via the AMSAT-NA “AMSAT-BB” mailing list.  Between posting an email to the AMSAT-BB and Twitter, you can get a lot customers for any satellite operation, rare DX/grid or not.  AMSAT-NA’s Facebook is a good place to post but it has a smaller audience compared to the openness of Twitter and the AMSAT-BB mailing list.  There are other mailing lists but they are private, individually-controlled lists (empires) that do not cater to the broader amateur radio audience.

Clayton’s pet peeve…politicin’ 2016
Many of us have multiple interests. I get that.   This is a very heated presidential election cycle.  I’m not a huge fan of cross-pollinating ham radio feeds with political views.  I’m certainly willing to discuss my views with any open-minded individuals who will engage in a two-way conversation…just not on Twitter.  However, what I find very annoying are people who re-tweet political garbage to their ham Twitter feeds.  Normally, I mute those feeds and disable re-Tweets from them.  In some cases, I just un-follow them completely and block them.

My AMSAT Field Day Report 2016 "from the road"

There is Field Day and then there is AMSAT Field Day.  Both events occur on the same day with very similar rules with one notable exception: AMSAT Field Day is entirely done via Orbital Satellites Carrying Amateur Radio (OSCAR’s.)

In the past, I have mostly participated in AMSAT Field Day from home but I have also known to be on the road.  In 2012, I was traveling with my family to New England and only stopped to listen to a few FM Satellites. That was quite interesting.  From Skyline Drive in Northern Virginia, I was able to hear stations trying to use AO-27 before the transponder had even been activated. There was a telemetry period before the transponder would activate.  During that telemetry period, I was hearing dozens of stations hollering “CQ Field Day” on the uplink frequency.  That was eye-opening.

This year we were heading to Amarillo, Texas on the Saturday of Field Day.  I didn’t arrive at camp until late afternoon.  However, there was plenty of time to setup my station and work a few passes.  I hadn’t planned on really making a strong attempt at FD this year being that we were away.  However, it is always fun to work some friends via satellite and listen to some of the FD madness.

As I predicted, SO-50 was total garbage.  Too many stations transmitting and few were able to hear. Absolutely pathetic!  It is selfish individuals who don’t operate satellites EVER but decide to try once a year that really ruin it for everyone.  Some are overconfident jerks who have made a couple of contacts in the past but think they have it all figured out when it comes time for Field Day so they don’t need any practice.

FO-29 was sad this year.  Many stations that were running excess power and couldn’t hear. This is evident by all the CQ’ing, HOLA, and 1-2-3 on top of other stations.

It is amazing to me that so many stations overlook the simple fact that you can make satellites contacts (on all current LEO birds) with 5 watts and an Arrow antenna.  Why run 100 watts into a giant array? Are you trying to look like a tough guy?  Are you compensating for something?

I did a fair job with my short Arrow and 20 watts.  I was using my 35ah battery to supply the Icom IC-821.  I worked LilacSat-2, XW-2C, XW-2F, and FO-29.  Not counting a few extra stations that called and worked me on LilacSat-2, I made 7 unique contacts that count for the AMSAT Field Day score.  Not bad for just a handful of passes in a mediocre operating location.

My normal “heavy” /P station.  IC-821 & Arrow.

View to East from my campsite in Amarillo, Texas

K5L /MM special event satellite operation from grid EL58hx

On Thursday, May 26, I made a visit to gridsquare EL58hx in far southeastern Louisiana.  It was a great adventure.  I intend to write more detail for a future article but I wanted to share a few sneak peeks with my blog readers.

There is plenty of GoPro and DJI Phantom3 footage.  I intend to put together a short montage available on YouTube at sometime in the future.

Until then, here are a few pictures of the operation:

Doing secondary GPS check before we dropped anchor.

Drone footage of me working a western pass.

More drone footage of me working a western pass.

Working an eastern FO-29 pass.

Another view to the west across the Gulf of Mexico.

Working the final FO-29 pass of the day.

A Tale of Two Antennas: What you can do in ideal locations with a handheld yagi

March 2016, my family took a short holiday to the Quachita Mountain National Forest on the Arkansas/Oklahoma state lines.  The grid square is EM24.  We were camping in our travel trailer at Queen Wilhelmina State Park.

During the week, Dave KG5CCI came to visit.  He lives in Little Rock in neighboring grid EM34. Dave has some family in the area so it was convenient for him to come play in the mountains with me for one afternoon.

While we didn’t have the opportunity to work many satellite passes together, we did have a lot of fun on one AO-7 and one FO-29 pass.  Dave made a good contact with the UK on a ~2 degree window from one of the many overlooks along the Talimena Scenic Road (Ark. 88.)

We stopped along another overlook as we made our way to camp and worked one FO-29 pass together.  He setup his station a few meters away.

During station setup, we had a little fun demonstrating polarity (mis)alignment:


We worked a nice FO-29 covering most of North America.  At the end of the pass, Dave and I played a little bit with “how low could we go.”  With me using the short Arrow and Dave using the full Alaskan Arrow, we were able to work each other below -1 degrees elevation.  You can hear us talking about it to each other VIA FO-29 on this little clip:
Stations:
KG5CCI – Icom IC-821h and Alaskan Arrow (10 ele 70cm, 4 ele 2m)
W5PFG – Icom IC-821h and Short Arrow (4 ele 70cm, 2 ele 2m)
Folks, Dave KG5CCI has a great place to play radio.  You can see how this location is excellent for stretching the footprint and making extreme DX contacts in his backyard.
Location, location, location.  

Satellite radios: Don’t lock those VFO’s on LEO’s (satellites)

DISCLAIMER: This entire blog post is focused on manually tuning your satellite radio to make contact via linear transponders (SSB/CW.)  If you are using computer control of your rig for Doppler Shift correction, some of the comments  below will not apply.

Most popular satellite radios such as the Kenwood TS-2000, Icom IC-910h, and the Yaesu FT-847 offer a mode to “track” satellite frequency movements.  There are normally two types of tracking, Normal and Inverse.  Your rig or software may refer to Inverse as Reverse.

Inverse tracking moves your uplink and downlink frequencies in opposing directions.  If you move one VFO up 10 kHz, the other VFO will go down in frequeny 10 kHz.  The majority of amateur satellite transponders in orbit utilize inverse tracking.  Inverse tracking is the most common practice.

Normal tracking moves your uplink and downlink frequencies together in the same direction.  Only one satellite operational today does this – AO-7 in mode A.  (note: Mode B is inverse)

It is important you have the correct tracking mode selected for each satellite before you go any further.

Most of the manuals for true satellite radios explain how to find your own uplink or downlink signal.  I won’t go into that on this blog post.  I want to cover an important topic: DO NOT DEPEND ON YOUR SATELLITE RADIO’S LOCKED VFO’S TO KEEP UP WITH DOPPLER SHIFT.  I intentionally bolded and capitalized that entire sentence.  It is very important.  You will always need to make manual adjustments as long as you aren’t controlling your rig’s VFO’s by computer.

The radio’s internal VFO locking does not really have anything to do with Doppler shift.  It simply locks the VFO’s so that they move equally with each movement of the main VFO knob.  This will not properly tune your station to the same frequency as another station on the satellite passband.

If you try to have a QSO with someone while your VFO’s are locked, you will look like a lid because every time you move your VFO knob, the uplink/downlink frequencies are technically moving away from each other in an unnatural manner, not how Doppler shift is affecting the uplink/downlink relationship.

It’s fine to lock the VFO’s and move to another part of the passband but it is not sufficient for staying in one place and having a QSO.  Once you “land” somewhere, unlock and tune the sub or main band VFO depending on the satellite mode (V/U aka J or U/V aka B.)  This is where the  Updated One True Rule comes into play.

Remember, we tune the higher of the two frequencies.  Examples:
AO-7, AO-73, XW-2 linear transponders: tune uplink
FO-29: tune downlink
If you lock the VFO’s, you will be tuning BOTH!
(that’s okay if you are using computer control and it’s done automatically and properly)

Final thoughts:

I highly recommend reading “The One True Rule for Doppler Tuning” by Paul, KB5MU and the updated “Bringing the One True Rule of Doppler Tuning into the 21st Century” by Alan, WA4SCA.

Buy a copy of AMSAT’s “Getting Started With Amateur Satellites.”  It covers this topic well and includes the above two abstracts.

More fun with the Short Arrow

This week, I decided I’d try out some new LMR-240uf jumpers that had arrived. Most of the jumpers I use in my portable station are 10′, either the LMR-240 (stiffer/solid center) or the LMR-240uf (UltraFlex, stranded center.)

For a few years I’ve really loved the stiffer LMR-240 and it’s never been a problem.  However, at a friend’s insistence I went ahead and made some LMR-240uf jumpers.  I’ve yet to notice a big difference however, I’d probably use the solid center if I was making some record-breaking attempt.

Since there was a LilacSat-2 pass rising, I decided to test the jumpers on that pass from my patio, facing east.  Here’s the catch: I wanted to use a single Yaesu FT-817.  Yes, it would be semi or “half” duplex (not my favorite/recommended,) but it was a good chance to test both jumpers.  Before I used them on RF, I did do a quick continuity check with my VOM to make sure the cables had no short.
How can I test both jumpers on the FT-817 without using the Arrow diplexer you ask?
The FT-817 has two antenna ports.  Simply configure UHF for one port and VHF for the other.  You do this by going to the band and selecting the antenna in your menu: Front or Rear.
Since both jumpers are terminated with BNC males, I did need to use an adapter on the FT-817’s rear SO-239.  It’s not my recommendation to use adapters since they are prone to failure and can sometimes be lossy (especially cheap ones.)  

 

All in all, it was a quick and easy test.  I made 3 contacts on this pass: Tennessee, Ohio, and Colorado.

Omnis, Dipoles, Eggbeaters, Moxons, Turnstiles for Satellite Antennas

I am not a fan of omni antennas for the current LEO satellites. The eggbeater or moxons are marginal performers at best.

Short, quality feedlines and RX preamps are good ways to minimize ineffectiveness of omnis but there’s no silver bullet.

If you have no other choice but omnis, you may find yourself limited to certain satellites** and certain passes. SO-50, for example, is not going to be favorable. Compensating for lack of hearing ability by running full power won’t make you many friends.

Working satellites on an almost daily basis, one can often identify an eggbeater or omni user by their inability to hear a very strong signal from the satellite.  Usually these operators have a strong signal but can’t hear themselves or another strong station calling them.

A set of small yagis at a fixed elevation with an azimuth rotor will yield far better results. The trick is not using longer, high-gain yagis. You’ll have more beam width with smaller ones. Considering what many stations achieve with an Arrow or Elk antenna (7,000+ km contacts,) bigger isn’t always better.

Bottom line:

  1. Omnis are okay as long as you understand the shortcomings.
  2. You may make some contacts with omnis.  Try it but don’t invest much money or effort into them.
  3. Omnis are an okay choice if you have no other option but to eliminate the need for a rotor.  I realize sometimes there are operational constraints.
  4. Don’t expect consistent AOS to LOS performance with an omni unless you have a great view of the horizon and sky in all directions and a very low-noise RF environment.

** The best satellites for omni’s are likely going to be mode B (U/V) SSB transponders like AO-73, XW-2A, XW-2C, XW-2F. AO-7 will be okay at times depending on health and elevation of pass.  FO-29 will be marginal if you pick the right passes.

Organizing my W5PFG/P Satellite Station for Portable Trips

One thing on my list for a while has been to acquire and setup the right size carrying cases to travel with and protect my investment in portable equipment.

Over Christmas I acquired a Pelican 1500 (yellow, as shown below.)  The Icom IC-821h fits perfectly inside along with the microphone.  I could probably make room for the power cord but at the moment, my cord is a bit long and doesn’t coil compactly.

The second case is a Plano Protector Series #1404.  It is not waterproof or nearly as rugged as the Pelican case but it holds all of my accessories and adapters needed for /P securely.

Aside from my coax jumpers and antennas, everything fits neatly into each box.
Box 1:
  1. Icom IC-821h Transceiver
  2. Icom Microphone

Box 2:

  1. Heil Dual Pro-Micro Headset
  2. Heil hand-trigger PTT
  3. Heil adapter for IC-821h
  4. Sony digital recorder
  5. Spare batteries for digital recorder
  6. Icom power cable
  7. Spare power cable and cigarette plug (for emergencies)
  8. Belkin 5-way audio splitter (to take audio out and feed to headset and digital recorder)
  9. Compass
UPDATE: One reader pointed out that my use of the Belkin 5-way audio splitter was hypocritical since I gave him a hard time for using one in his portable setup.  I must confess, he’s right.  I normally do not need to split audio more than 2 ways (to headset and recorder) but sometimes it’s convenient to be able to have an audience listen. 

Central States VHF Society CS-VHF Reverse VUCC Award – Satellite

After operating from over 100 different grid squares, I decided it was time to apply for the Central States VHF Society (CS-VHF) Reverse VUCC Award.

Arliss, W7XU checked my cards and issued the award last week, December 9, 2015.

Thank you, friends, for all the great QSO’s while I’ve been on the road!

The award is issued in increments of 25 starting at 100.  I’m now at 117 grids but don’t really plan on increasing my endorsements any time soon.