Practical use for SSTV with UNDR Net

 

Our 4th and final UNDR Net of September ended with a unique plot twist. Our weekly theme followed the Federal Emergency Management Agency (FEMA) National Preparedness Month guide via a quick mention of helping youths to be prepared for disasters.

As we have learned in past weeks, the star of the show has been our testing of SSTV over FM with this week being the first time we had three different licensed amateur radio operators broadcasting images through the Overlook Mountain Amateur Radio Club repeater in the Hudson Valley. 

The reason why we are experimenting with this mode of communications is to raise awareness that there is more to just voice capability which a VHF analog repeater can be used for. It is also proving to be another great opportunity to get more familiar with what can be done with equipment you already have at minimal expense.

Should the need arise, using just your existing handheld amateur radio and a smartphone, you can send and receive images with little prior knowledge. This capability may come in handy in a time when you may not have cellular network access, but have a perfectly charged smartphone.

Round Number One

Ken KD2TQS in Rhinebeck led us off with the following image sent in order to spur discussion on about an upcoming special event focused on radio direction finding.

It was nice to welcome Brad KC2VVJ back on the air and to the UNDR Net. The above image was received by him in Washingtonville while parked stationary in his car.  Some of the blurring is mainly due to noise picked up by the microphone in his smartphone, but is otherwise clearly legible.

This image took about 50 seconds to send using the PD50 mode of slow scan television, which is also used by the International Space Station but they often send with PD120 which is twice as long but better resolution like some of the examples here shared by Steve K2GOG. 

Round Number Two

The next image was sent by Steve K2GOG in Poughkeepsie and was also received by Brad KC2VVJ in his car with a noticeable amount of extra noise. 

This week the UNDR Net had a total of eleven participants, including the following who were able to also decode the image and its details were discussed.

Thank you to Paul N3EYQ in Rosendale, Tom N2ZFC in Fishkill, Jim KD2VAH in Poughkeepsie, Guy KD2TLF in Xena, Lou KD2TVS in West Milford (NJ), Ken KD2TQS in Rhinebeck, John K9JPT in Hopewell Junction who all were able to receive the image and share details.

Fellow HVDN and Overlook Mountain Amateur Radio Club member Bob KD2QAK will be giving a presentation on orienteering in October as a virtual video to help provide some useful tips which may be used during the upcoming "Fox Hunt" scheduled for October 30th 2021 at Ferncliff Forest in Rhinebeck.

The weekly theme of the UNDR Net in October will focus on radio direction finding, so be sure to listen in for that plus continued testing of SSTV over FM. 

During the upcoming hidden transmitter hunt which is sometimes called a "Fox Hunt" the signals that will be sent may include SSTV, so its going to be a lot of fun for those who can find the transmitter as well as decode its secret images.

Round Number Three

This time Brad KC2VVJ took a turn sending images and we also were later joined by Brian KD2SQO, Bob K2LD and Mike KC2UVP as late UNDR Net arrivals.

For those that frequent the WA2MJM wide area 146.805 MHz repeater, the below image will make sense as Brad's profession involves the sharpening of knives.

The above image is the original which Brad sent and many got a good laugh out of it, but no one sent in a reception report so we can give them credit for receiving the image.   We have a website set up should anyone wish to share results using the form at hvdn.org/undr.

Round Number Four (And a twist!)

The final image of the night was going to be the most simple one and Brian KD2SQO was first to report he received it. However, soon after additional signal reports it was discovered that Brad KC2VVJ had curious visitors which included a neighbor and a local first responder who heard "strange things" coming from Brad's vehicle.

Neither of them believed he was sending and receiving images with nothing more than a radio which did not include any internet connectivity.   Thinking quickly, Brad quickly made an image of "2+4=6" and sent it out asking our participants to read back what he sent.

Almost all at the same time, Bob K2LD, Tom N2ZFC and a few others all started shouting back the above numerical equation to the astonishment of the curious audience Brad had.

Practical Uses for SSTV

The most common use today for SSTV is mainly on the lower frequency band known as 20m on a frequency of 14.230 MHz but often only includes images sharing postcard type images and callsign of the sender or receiver.  While fun, this has little practical use but does showcase long range communications capability.

Local communications in the 50 to 100 mile range or even closer can greatly benefit by more use of SSTV as being demonstrated over the past few weeks.

Much better image quality can result by connected a wire between the smartphone and handheld radio.  This will certainly happen in October now that many have seen it is possible to send decent quality photos without that extra accessory.

The Easy Digi™ Digital Sound Card Interface by KF5INZ is low cost and allows most radios to be connected to a smartphone.  The great news is that you can send or receive much more than just SSTV, but also text using modes such as RTTY or PSK as well as forms used in emergency communications like NBEMS. 

Adding this interface to your personal emergency kit along with a handheld radio is a great low cost way to further show interesting things with amateur radio. 

UNDR Net October Schedule

With both a virtual and in person event planned in October, our weekly radio discussion will also shift responsibility to a group of net controllers.  Right now this includes Steve K2GOG, Ken KD2TQS and Brad KC2VVJ.  All of them are working closely together to provide curriculum and assistance to those interested in what we are doing on and off the air.

If you would like some personalized help with SSTV, Ken KD2TQS is making himself available and you can reach him using the form on the hvdn.org/undr webpage.

Steve K2GOG is going to be focused on organizing the RDF event on October 30th and Brad KC2VVJ will be working with Bob KD2QAK regarding the online presentation on using a map and compass.

Lots of fun is ahead for UNDR Net and we would like to continue to thank our area partner clubs such as the Overlook Mountain Amateur Radio Club and also the West Point Cadet Amateur Radio Club for finding ways we can all work together to promote the modern evolution and convergence of amateur radio with other interests.