The Amateur Amateur: Hamityville Horror
By Gary Hoffman, KB0H
Contributing Editor
September 29, 2005
The den suddenly turned into a scene right out of the movie Poltergeist. One
of the lamps started flickering. Just more adventures as The Amateur
Amateur delves more deeply into SSTV.
This is what I pieced together for my first SSTV attempt.
An instant reply from Cuba!
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In the my
last few columns I related how curiosity about PSK31 had led me into
the field of digital modes and in particular Slow Scan Television
(SSTV). Klaus Kramer, DL4KCK, pointed out that SSTV is usually
analog, so it would be more proper to say that I was exploring
data modes rather than the
digital modes. In any case,
I decided to play around with SSTV some more.
It was one thing
to sit back and admire the pretty pictures scrolling across my
computer screen and quite another to actually
send them. For
unlike voice modes, or even many data modes, I could not simply jump
in and start talking (or typing). I needed a picture to send. And,
don't forget, I also needed to send my call sign.
The
MMSSTV
freeware program I was using had some tools to help build and prepare
images for transmission. I dug up an image of me sitting at my
station and fed it into the program. It accepted the simple JPEG
image and cropped it to the correct size. I inserted some text and my
call sign, and my picture was ready for transmission.
In the meantime
my wife Nancy had gone to our den and settled into the La-Z-Boy with
a mystery novel. As long as I don't have the volume cranked up too
loud she doesn't mind the strange noises emanating from the basement.
Back downstairs I
was still contemplating sending my first SSTV transmission. There was
activity on the 20 meter band, and images kept appearing on my
display. I didn't see much in the way of dedicated conversations.
Mostly I saw individual operators sending pictures with
CQ in
them. Sometimes there would be a reply with the call signs of both
the sender and intended receiver superimposed on the image. That
evening the people sending images just seemed to want to make a lot
of contacts. I felt that the environment was perfect for sending my
own first image.
Still curled up
with her book, Nancy was trying to ignore the weird sounds wafting up
from the basement. She'd heard a lot of noise before, mostly static
and distorted voices, but tonight the sounds were downright eerie. It
was more like the sound track to
Star Wars than the ham radio
racket she was used to hearing.
I had
MMSSTV
all prepared. My image was loaded and ready to go. I waited for a
relatively quiet moment and then hit the
TRANSMIT button. The
program indicated that it was sending the image and my transceiver
started transmitting. And transmitting. And transmitting. One thing I
had forgotten is that it takes a while to send out a complete
picture. My hands were getting sweaty as I worried about how long my
transmission was. I was relieved when my transceiver finally clicked
back into receive mode.
The den suddenly
turned into a scene right out of the movie
Poltergeist. A
three-way bulb in one of the lamps started flickering, then switched
from bright to dim, dim to medium, medium to off, and so forth in a
random sequence. The printer connected to the computer in the den
started going through odd cycles, even though the computer itself was
turned off. Nancy kept looking from the printer to the lamp and back
again, wondering what in the world was happening.
Back down in the
shack I was blissfully unaware of the mayhem in the den. I waited to
see if anyone responded to my transmission. Hardly a few seconds
lapsed before an incoming image started to assemble on my screen. I
gasped. It was a reply to my transmission, and it was from Cuba! My
very first attempt at SSTV had netted a DX contact!
Upstairs in the
den Nancy's world had become sane again. The lamp had stabilized on
one setting and the printer had returned to a dormant state. The only
thing that had changed was that the weird noises in the basement had
resumed. It had been quiet during the lunacy with the electrical
devices.
Hmmm.
Just touch this lamp to turn it on. Or have your spouse transmit a SSTV
signal.
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Not realizing that a storm was brewing upstairs I ogled at the image I'd
received from Cuba. I wanted to reply at once. I turned to the
keyboard and . . . had no idea what to do. I only had one picture.
Moreover it had taken me half and hour to set up that single image.
There was no way I could build a reply image and send it promptly.
Well, obviously there
was a way since the fellow in Cuba had
put together a picture with both of our call signs on it within just
a few seconds. But he was clearly adept at building quick replies,
and I was not. I sighed and turned to my log book. At least I could
note the contact. Then I'd go upstairs and tell Nancy about my good
fortune.
I entered the
den, grinning from ear to ear. Just wait until Nancy heard about my
SSTV contact with Cuba!
"What in
blazes were you
doing down there!?" she snapped.
Being a fan of
Pinky and the Brain I was tempted to reply, "The same
thing I do every night, Pinky," but the look on her face caused
my childish exuberance to evaporate. I just gaped at her as she
described the antics of the seemingly haunted electrical devices.
Okay, here's the
story. My HF antenna system is a suburban compromise. This mean it's
far from perfect. It sits too close to the roof, and the current node
is too close to the den. I already knew that it was a bit of a
problem, but it wasn't until I transmitted a lengthy image that the
extent of the problem became apparent.
So my ecstasy
over my near-successful SSTV contact was tempered by the realization
that my antenna system needed yet another overhaul. Pouring more
radio energy into the den and whoever happened to be in it just was
not acceptable. It was time to get serious and start contemplating a
new solution to my HF antenna dilemma.
By the way, did I
mention that I received a SSTV signal from Cuba?
Editor's note: ARRL member Gary Hoffman, KB0H, lives in Florissant,
Missouri. He's been a ham since 1995. Hoffman says his column's name
-- "The Amateur Amateur" -- suggests the explorations of a
rank amateur, not those of an experienced or knowledgeable ham. His
wife, Nancy, is N0NJ. Hoffman has a ham-related
Web page.
Readers are invited to contact the author via e-mail,
[email protected].
© 2005 American Radio Relay League