You Can’t Tell the Digital Modes Without a Scorecard

Unless you work the digital modes a lot, how do you tell which signal is PSK 31 and which is Feld Hell? By going to K2NCC’s YouTube page, of course! Frank has posted examples of nine different modes, including Domino, Feld Hell, SSTV, and MFSK16. What’s cool about these posts is that you not only hear what they modes sound like, but what they look like on a waterfall display.

Here’s what Domino EX16 sounds like and looks like:

Frank says, “Stay tuned for more!”

More Sweet Tweets

Here are some more links to interesting Web pages I found by Twittering:

  • N3OX’s Remote Tuner Control. N3OX has added some servo motors and controls to a manual antenna tuner so that he can move it closer to the antenna, but still control it from inside the shack. Very inexpensive solution.
  • Band Plans for 900 MHz and Above. KB9MWR feels that the future of ham radio is above 900 MHz. I don’t know that I totally agree, but I do think we need to start thinking more about those bands. Give this a read.
  • Morse Code vs. Text Messaging. Chas Sprague, who’s not a ham, ruminates on how Morse Code could make text messaging more efficient. I wholeheartedly agree! Someone get this man his ham ticket.
  • Ham Logging as a Service. There’s been a lot of twittering about this KE9V blog post. I like the idea myself, and if I had more time, I might even take a crack at it. Anyone want to collaborate?
  • Planning a Digital ATV Station. After pondering a digital ATV station for the museum, I opted to go analog. If I’d seen this article first, I might have opted to stick it out and go digital.

Digital TV?

For our Ham Radio at the Hands-On Museum project, we want to set up a television station. My first thought was to buy a transmitter from PC Electronics that sends standard-scan analog TV. Then, I got to thinking, why bother with that? If our goal is to show that we’re at least up with current technology, then shouldn’t we be doing digital TV?

I have found a bunch of European hams doing digital TV using the European standard and one page of links on DXZone:

So far, though, I haven’t seen anything on ATV using the new US standard. Is anyone out there experimenting with this or even making gear that I can purchase?

900 MHz??

Someone recently offered to give our club a 900 MHz repeater. 900 MHz?? Who uses that band Well, apparently, there is a lot of activity up there, and maybe the least of it amateur activity.

I got to thinking about how we might use it. The first thing to cross my mind was digital TV. Other kinds of digital apps, such as some kind of instant messaging, might also be interesting.

Here are some resources:

  • Exploring 900 MHz by KB9MWR. Some good basic information on the band and equipment you can use there.
  • AR902MHz Yahoo Groups Mailing List. This list has more than 1,400 subscribers and is relatively active.
  • San Diego 900 MHz ARC. General info on 900 MHz as well as specific info on what’s going on around San Diego.
  • GEMoto.Com. This is a networking group made up of mostly New England hams interested in converting and using GE and Motorola commercial radios. According to Ben, N1WBV, there’s a fair amount of 900 MHz activity around Boston because their use of 440 MHz is fairly restricted.

Digital Comms Conference, Sept 26-28, Chicago, IL

From WB9QZB via the HamRadioHelpGroup mailing list:

The ARRL/TAPR DCC (Digital Communications Conference) is being held in Chicago on September 26 – 28, 2008.

The DCC will be at the Elk Grove Village Holiday Inn located in Chicago’s northwest suburbs near O’Hare airport with a free airport to hotel shuttle and easily accessible from major interstate highways.

The DCC is the premiere, national, annual digital ham radio conference covering ALL the Digital Voice & Data technologies from HF to Microwaves.

There will be BOTH Technical & Introductory presentations covering all levels of experience with the digital modes and also an ARRL forum.

This year for the first time at the DCC there will be a D-STAR Friday Night event. We plan to have innovators, pioneers & leaders in D-STAR digital voice & data technology available to present and take your questions.

Icom will be at the DCC and TAPR plans to have it’s 70cm & 23cm D-STAR digital voice & data repeaters operating at the DCC connected to the internet gateway.

You can get more information about the DCC at http://www.tapr.org/dcc.html.

Reigster before September 1st & save $10 on your registration fee.

You can register at https://www.tapr.org/dccregistration.php.

Slow-Scan TV – My Next Digital Mode

Now that I’ve started having fun with PSK31, I’m getting interested in slow-scan TV (SSTV). The term SSTV can be a bit misleading, as there’s both analogue SSTV and digital SSTV. Digital SSTV signals must be less than 500 Hz wide. That allows them to be used in the same band segment as PSK31 and other similar digital modes.

To find out more, one place you can go is K3UK’s Quick and Dirty Guide to Narrow Bandwidth SSTV. It focuses on using the MMSSTV software, but has a lot of good info on operating practices as well.

Another resource is CQ SSTV de KB4YZ. This page has hundreds of links to other sites with SSTV information. There are almost too many links here. It’s hard to decide where to start.

Since I’m now using a Mac laptop in my shack, I was interested in what software is available for the Mac. KB4YZ has two links:

  • MultiMode for the Mac by Chris N3JLY. This is commercial software and costs $89. It looks pretty good, but I’m not sure if I want to spend $89 on it.
  • MacRobotSSTV for the Mac by Sergei KD6CJI. This looks like a nice program, but the User’s Guide notes, “currently USB audio input e.g iMic is not working.” Looks like I’m going to have to wait for the next version.

Small Wonder PSK31

A couple of years ago, I bought and built the SST-20 20m QRP rig from Wilderness Radio. While I haven’t had that much success with this rig–I attribute this to my poor antenna skills–the kit went together pretty easily and was fun to build. (If anyone wants to buy this from me, you can have it for the kit price: $85)

Now, I’m thinking of trying it again. This time with one of the PSK31 rigs from Small Wonder Labs. They make several different models, including one for 10m that looks relatively easy to put together. Apparently, these rigs interface directly to a 16-bit sound card.

As for the computer, I have an old Windows box that I was thinking of converting to Linux. Another possibility is to buy an old laptop for use in the shack. The advantage of the laptop is that it would take up less space in the shack. A third option is to try to get one of the Linux PSK31 packages to run on my Sharp Zaurus. A Google search for “linux psk31″ turned up quite a few references to PSK 31 software running on Linux machines.

I have a couple of questions:

  • Has anyone built one of the PSK31 units? Having any success with them?
  • Am I crazy for thinking about the 10m unit? Should I go with one of the other bands?
  • Is anyone running PSK31 software on a Linux box? Which package do you think is best?