[Heath] DSB...

[ChrisIwata]

I don't mean zero carrier DSB,  I mean suppressed carrier.  In modern 
day this amounts to unbalancing the balanced DSB modulator, so that some 
carrier is there even in the absence of modulation.

I'm not talking about the implementation,  I'm talking about the signal.

Yup, I agree controlled carrier AM is much easier to implement. Both on 
the transmitting end and the receiving end, compared to DSB.

Seems to me the signal generated by controlled carrier AM is the same as 
suppressed carrier DSB?   Neither one has zero carrier with no 
modulation, and the carrier increases with modulation.  I don't know, 
maybe the controlled carrier signal is not a linear representation of 
the modulation as is the case with suppressed DSB?  That is, if you 
speak twice as loud, the controlled carrier might not go up twice as much?

The one big feature of this signal is it can be detected with a simple 
envelope (AM) detector, just like plate modulated AM

When you think about it, aside from CW, modern ham radio communication 
has become very complex.  I guess this is why home-brewing is becoming a 
lost art.

Chris, KL7DM


On 5/19/2018 4:34 PM, Kenneth G. Gordon wrote:
> OK. I did some research: generating a DSB signal requires a balanced modulator
> somewhere in the system.
>
> In one case I remember, the two 1625s in an "ARC-5" transmitter were used as a
> direct-to-antenna DSB transmitter.
>
> The screens were fed push-pull audio, while the plates were parallel-connected. As I
> remember it, an oscilloscope was required to get it adjusted properly.
>
> DSB is far more complex than the simple controlled-carrier systems in our simple
> transmitters.
>
> If anyone here is interested, here is a link to the "Double-Sideband Junior" from GE Ham
> News of March-April 1958.
>
> http://n4trb.com/AmateurRadio/GE_HamNews/issues/GE%20Ham%20News%20Vol%2013
> %20No%202.pdf
>
> Ken W7EKB
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
> _______________________________________________
> Heath mailing list
> Heath at puck.nether.net
> https://puck.nether.net/mailman/listinfo/heath