Methods for generating single-sideband signals from LO and audio?

[cdev]

I have a Sofrock Ensemble III and I am wondering if it might be possible to also use it for transmitting with modifications. It has an internal oscillator to produce the VFO signal which is at four times the frequency of interest. And of course also the audio signal.

(what is the practicality of a ring modulator? https://en.wikipedia.org/wiki/Ring_modulation )

Does anybody know of a good source/summary of methods to generate a weak SSB signal? I am trying to get an idea if it might be practical to retrofit my cheap softrock receiver into a transceiver. (Its a great receiver, BTW, for the price)

My computer has a nice sound card that can do 24 bits. I am just asking, not doing anything. Of course I would also make sure any operation complied with all applicable laws and licensing reqts)

[bob91343]

There are two basic, classic methods to produce an SSB signal.  One is the phasing method and the other the filter method.  With modern techniques, however, the field has become more cloudy with innovative methods appearing often.

You would do well to consult the Radio Amateur's Handbook for some basic information, especially any edition in the 1960s.  You might also look at the schematic diagrams of transceivers, especially for amateur radio, built in the 1960s through the 1980s.   Some construction projects are shown in the Handbook as well.

[vk6zgo]

I have a Sofrock Ensemble III and I am wondering if it might be possible to also use it for transmitting with modifications. It has an internal oscillator to produce the VFO signal which is at four times the frequency of interest. And of course also the audio signal.

(what is the practicality of a ring modulator? https://en.wikipedia.org/wiki/Ring_modulation )

Does anybody know of a good source/summary of methods to generate a weak SSB signal? I am trying to get an idea if it might be practical to retrofit my cheap softrock receiver into a transceiver. (Its a great receiver, BTW, for the price)

My computer has a nice sound card that can do 24 bits. I am just asking, not doing anything. Of course I would also make sure any operation complied with all applicable laws and licensing reqts)

Historically, there were three methods of obtaining SSB signals.
(1) The filter method.
With this method, a balanced modulator was used to create a DSB signal.
This signal was then passed through, typically, a crystal filter to remove one sideband.
Most such transmitters did this at a fixed IF frequency, which was then converted to the frequency of interest using a mixer.

(2) The "phasing" method.
In this method , both the audio in & RF from the local oscillator were split into two signals 90 deg out of phase.

They then were fed to separate mixers, & the two resultant DSB signals were passively mixed, resulting in the cancellation of one sideband.(Sorry if this is vague, but it is too long since I last read anything about it)

(3) "The third method".This is a very complex extension of the phasing method, & what I don't know about it would fill a book!

The most modern designs use  DSP to obtain SSB----whether by digital filtering, or digitally performing the
hard part of one of the "phasing"methods, or some other method, I know not!                                                                              

[LaserSteve]

See the Philips AN1981 application note

N8VKD