We're cruising toward the 100 year anniversary of SSB. It definitely qualifies
as older technology.
It was the famous John Carson patent for SSB filed in 1915 that used the
antenna circuit for more than just radiating. He suppressed the carrier with a
balanced modulator but sliced off the opposite sideband in the antenna coupler.
That's a higher Q tuner than your average MFJ.
I've never understood why it took so long for amateurs to pick up SSB. AT&T had
it in commercial service in 1927. A couple of guys did stuff in the '30's. But
not until the Stanford experiments in 1947 and the QST articles the next year
did it really start to take off. Maybe it took cheaper and better components
that came out of WWII to make it practical for hams. Or maybe it was just
wasn't interesting to them.
On Feb 24, 2014, at 1:08 PM, k6jek wrote:
> There is a lot to be said for an antenna as a resonant circuit. One of the
> very early SSB patents did just that. They sliced off the carrier and
> opposite sideband at the antenna. Now if I can just remember who that was. I
> bet one of you can
>
>
> On Feb 24, 2014, at 12:42 PM, Ron Notarius W3WN wrote:
>
>> Loomis was a quack. I'd rather hang out with Reginald Fessenden
>>
>>
>> On 02/24/14, Rick - DJ0IP / NJ0IP wrote:
>>
>> Doug, I think you've been hanging out with Mahlon Loomas too long!
>>
>>
>>
>> And for those of you who can't remember who he was, it might be worth your
>> while to look it up.
>>
>>
>>
>> I bet most of you didn't even know that wireless communications was invented
>> by a DENTIST!
>>
>>
>>
>> Yes, he also invented the very first Aerial, although some might argue it
>> was Benjamin Franklin.
>>
>> Franklin only used the kite wire to capture electricity; Loomas used it as
>> an Aerial to send and receive signals.
>>
>> http://en.wikipedia.org/wiki/Mahlon_Loomis
>>
>>
>>
>> Though his patent for a wireless telegraph was in 1872, as I recall he
>> discovered this about 4 years earlier. Hard to remember exactly. I was
>> just a young whipper snapper back then.
>>
>>
>>
>> So guys, take it from me; next time you're having problems with your
>> antenna, don't ask an engineer, consult your dentist!
>>
>> Hey, I oughta know... I work for an antenna company!
>>
>> ;-)
>>
>>
>>
>> What does all of this have to do with Doug's comment?
>>
>> Everything.
>>
>> Mahlon discovered that if he made the length of the wire of the TX and RX
>> aerial the exact same length, communications was much more reliable. Thus
>> you might conclude that the length of wire was determining the frequency.
>>
>>
>>
>> But that's not quite accurate.
>>
>> Actually it was transmitting on (almost) all frequencies, but only
>> efficiently radiating into the ether on the wavelength associated with the
>> length of his aerial. So specifically, the aerial, not the transmitter,
>> determined the frequency being radiated into the distant ether. In the near
>> field, a broad frequency spectrum was being radiated.
>>
>>
>>
>> ... at least that's my understanding of what was happening.
>>
>> Then again, how would I know?
>>
>> I'm neither an engineer nor a dentist!
>>
>>
>>
>> 73 - Rick, DJ0IP
>>
>> (Nr. Frankfurt am Main)
>>
>>
>>
>> -----Original Message-----
>> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Doug Reid
>> Back when I started out, we used a spark generator and the frequency was
>> determined by the length of our antenna......
>>
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