Normal speech is by its nature asymmetrical which is why AM broadcasters use
automatic phase rotators in their processing equipment to make sure the side
of the waveform with the highest peaks is in the right direction. No need
for DC offset if it's done right.
Ron N6IE
www.N6IE.com
----- Original Message -----
From: "Dr. Gerald N. Johnson" <geraldj@weather.net>
To: <tentec@contesting.com>
Sent: Saturday, June 12, 2010 6:59 PM
Subject: Re: [TenTec] re Orion AM ALC
> Now you are delivering distorted audio to the modulator, probably with
> some DC offset that isn't supported by capacitor or transformer coupled
> audio stages.
>
> To get asymmetrical modulation without over modulating going negative,
> you have to introduce the asymmetry AT the modulator, not before and the
> modulator has to be DC coupled at audio.
>
> 73, Jerry, K0CQ
>
> On 6/12/2010 8:55 PM, Rob Atkinson wrote:
>> Merle,
>>
>> What happens if you deliver asymmetric peaks, say 130% positive and
>> around 95% negative, to the rig? Sounds the firmware is programmed
>> with the assumption everyone runs symmetric up and down.
>>
>> 73
>>
>> Rob
>> K5UJ
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