What became known as Exalted AM was really a technique that was used
back in the later spark era days once they developed nearly CW sources.
In fact that is where the term local oscillator and BFO came from. They
discovered
if an oscillator near the frequency you were receiving was coupling into the
diode detector,
you not only had a beat tone but the sensitivity increased over 100 times
sometimes up to
500 times. This was because the detector was being over driven to saturation
during have
of the oscillator cycle and was behaving as a RF switch. It was performing more
as a
product detector rather than a square law detector. In fact Marconi Patented
the first
balanced product detector in 1916. It used a buzzer and high Q tank circuit for
the BFO or
Local Oscillator. Local oscillator means an oscillator near the detector.
By the way, another interesting fact, unrelated, Hertz discovered the photo
electric effect
before 1900.
73
Bill wa4lav
________________________________________
From: Carl [km1h@jeremy.mv.com]
Sent: Thursday, September 12, 2013 9:49 PM
To: Fuqua, Bill L; Joe Subich, W4TV; amps@contesting.com
Subject: Re: [Amps] S/S Amp's
By using the Exalted AM method that goes back 70 years you dont need a fancy
radio.
Modify the BFO for variable injection level and connect to the last IF
thereby maintaining AGC. Its almost as good as a sync detector for selective
fading and its easier to follow a slightly drifting carrier.
Carl
KM1H
----- Original Message -----
From: "Fuqua, Bill L" <wlfuqu00@uky.edu>
To: "Joe Subich, W4TV" <lists@subich.com>; <amps@contesting.com>
Sent: Thursday, September 12, 2013 4:14 PM
Subject: Re: [Amps] S/S Amp's
> Most hams today can't tune SSB clearly.
> AM always sounds right. Perhaps we should have SSB reduced carrier rather
> than
> suppressed carrier. Another point, DSB occupies same bandwidth as AM.
> You could receive DSB or AM by detecting, using bfo and SSB filter, only
> one sideband but with the loss
> of 3dB signal to noise ratio compared to receiving it with synchronous
> detector.
> 73
> Bill wa4lav
>
> ________________________________________
> From: Amps [amps-bounces@contesting.com] on behalf of Joe Subich, W4TV
> [lists@subich.com]
> Sent: Thursday, September 12, 2013 2:29 PM
> To: amps@contesting.com
> Subject: Re: [Amps] S/S Amp's
>
> For the same reason they spam other bands with ESSB, IM products,
> keyclicks, splatter and/or full carrier AM - because they can and
> the rules against stupidity, and bad operating practices either do
> not exist or are not enforced.
>
>
> 73,
>
> ... Joe, W4TV
>
>
> On 9/12/2013 12:14 PM, qrv@kd4e.com wrote:
>> Why are Hams still rf-spamming 160 & 80m with AM carriers
>> when a DSB suppressed-carrier signal is just as good, uses
>> less power, and may be sync-detected to remove flutter, etc?
>>
>> I know, I know, ... never mind ... sigh.
>>
>>> Jim said;
>>>
>>> "It sure would be nice to just rectify the 120vac from the wall plug,
>>> with
>>> or without any isolation xfmr"
>>>
>>> It's already in production.
>>>
>>> Not quite what you're after but... <http://www.k7dyy.com/>
>>> http://www.k7dyy.com/
>>>
>>> David G4ZOW
>>
>>
>>
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