The classic SSB-AM signal was that generated in the Collins KWS-1 of 1956.
I agree, it's not exactly a transceiver, but another example of that
kind of signal.
If received in a receiver with 3 kHz filter, the SNR of such a SSB-AM
signal should be the same as with a DSB-AM signal of the same carrier
level in a 6 kHz wide receiver. It also takes up less spectrum.
Joel Hallas, W1ZR
Ken Brown wrote:
>Most SSB capable transceivers, that can also transmit in AM mode, do so
>using the same balanced modulator that they use to produce DSB. When in
>SSB mode the DSB output of the balanced modulator is run to a filter to
>reject the unwanted sideband. When transmitting in AM mode the filter is
>usually bypassed to allow both sidebands to be transmitted, and the
>modulator is either unbalanced to let carrier through, or the carrier is
>reinserted in a later stage.
>
>Some transceivers ( such as the Kenwood TS-440 ) have independent
>control of TX audio level and carrier level, so that when AM mode is
>selected you can be transmitting anything from DSB with virtually no
>carrier (requiring the receiving station to have his BFO on, and zero
>beat to your suppressed carrier) to full carrier level AM, or even just
>a carrier with no sidebands at all, depending on how you adjust the
>controls.
>
>Some transceivers ( such as the Kenwood TS-50 ) have preset carrier
>level when selecting AM transmit mode, so that DSB with no carrier is
>not an option.
>
>A very few transceivers ( such as the Ten-Tec 586 Paragon II, and I
>don't know of another ) when transmitting in AM mode generate a DSB
>signal with their balanced modulator, filter it to remove one sideband,
>and reinsert the carrier, producing "SSB AM" rather than "real DSB AM".
>With the Paragon II you can select which sideband you want to transmit,
>and both sidebands (DSB) is not an option. When receiving AM with the
>585 Paragon or 586 Paragon II, you can listen to either sideband or both
>sidebands, depending on the IF filter you select and the setting of the
>VFO and Passband Tuning controls.
>
>The 585 Paragon cannot transmit AM in any form (other than SSB with no
>carrier), only the 586 Paragon has AM TX capability.
>
>DE N6KB
>
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>
>
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