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If you're close enough they'll hear you but you'll get the changes in audio you're experiencing above.

When you see discussions on "hi-fi" cb you'll notice they are usually throwing numbers in the range of up to 4 or 5 kHz around, this number is the freqency that the audio energy is transmitted at in relation to the carrier. If your audio bandwidth is about 4kHz that means that you are transmitting at your carrier frequency +/- 4kHz for a total of 8kHz on AM or 4kHz total on SSB as only the plus or the minus but not both are transmitted. A 1kHz audio tone would be 1kHz away from the carrier, a 2kHz tone would be 2kHz away from the carrier. The closer the modulated power is to the carrier the lower the pitch, the farther from the carrier the higher the pitch.

Now if you are transmitting on 27.3848 and transmit a 2000Hz (2kHz) tone on AM you will have power going out at 27.3848 (your carrier) as well as spikes at 27.3868 (2000Hz tone on USB) and 27.3828 (2000Hz tone on LSB). On SSB the carrier and one of the sidebands audio tone would be filtered out and not transmitted.

Now if he was listening at the same frequency a 2,000Hz tone would sound like 2,000Hz because it is 2,000Hz away from the carrier his receiver is generating. With him being on 27,3850 the carrier being generated in his receiver is 200Hz higher than the one used by your transmitter, as a result the frequency of the audio tones as perceived by his receiver will change. On USB the 27.3868 spike will be 1,800Hz above his receivers center frequency and sound lower in pitch, on LSB the 27.3828 spike will be 2,200Hz away from his center frequency and sound higher in pitch. If his center frequency is far enough away from yours that it puts your transmitted power outside of his receivers filter bandwidth he won't hear you at all.

Or something like that.

<blockquote data-quote="StrangeBrew" data-source="post: 594421" data-attributes="member: 21357">If you&#039;re close enough they&#039;ll hear you but you&#039;ll get the changes in audio you&#039;re experiencing above.When you see discussions on &quot;hi-fi&quot; cb you&#039;ll notice they are usually throwing numbers in the range of up to 4 or 5 kHz around, this number is the freqency that the audio energy is transmitted at in relation to the carrier. If your audio bandwidth is about 4kHz that means that you are transmitting at your carrier frequency +/- 4kHz for a total of 8kHz on AM or 4kHz total on SSB as only the plus or the minus but not both are transmitted. A 1kHz audio tone would be 1kHz away from the carrier, a 2kHz tone would be 2kHz away from the carrier. The closer the modulated power is to the carrier the lower the pitch, the farther from the carrier the higher the pitch.Now if you are transmitting on 27.3848 and transmit a 2000Hz (2kHz) tone on AM you will have power going out at 27.3848 (your carrier) as well as spikes at 27.3868 (2000Hz tone on USB) and 27.3828 (2000Hz tone on LSB). On SSB the carrier and one of the sidebands audio tone would be filtered out and not transmitted.Now if he was listening at the same frequency a 2,000Hz tone would sound like 2,000Hz because it is 2,000Hz away from the carrier his receiver is generating. With him being on 27,3850 the carrier being generated in his receiver is 200Hz higher than the one used by your transmitter, as a result the frequency of the audio tones as perceived by his receiver will change. On USB the 27.3868 spike will be 1,800Hz above his receivers center frequency and sound lower in pitch, on LSB the 27.3828 spike will be 2,200Hz away from his center frequency and sound higher in pitch. If his center frequency is far enough away from yours that it puts your transmitted power outside of his receivers filter bandwidth he won&#039;t hear you at all.Or something like that.<img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f609.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=";)" title="Wink&nbsp; &nbsp; ;)"&nbsp; data-smilie="2"data-shortname=";)" />&nbsp;&nbsp; </blockquote>

[QUOTE="StrangeBrew, post: 594421, member: 21357"] If you're close enough they'll hear you but you'll get the changes in audio you're experiencing above. When you see discussions on "hi-fi" cb you'll notice they are usually throwing numbers in the range of up to 4 or 5 kHz around, this number is the freqency that the audio energy is transmitted at in relation to the carrier. If your audio bandwidth is about 4kHz that means that you are transmitting at your carrier frequency +/- 4kHz for a total of 8kHz on AM or 4kHz total on SSB as only the plus or the minus but not both are transmitted. A 1kHz audio tone would be 1kHz away from the carrier, a 2kHz tone would be 2kHz away from the carrier. The closer the modulated power is to the carrier the lower the pitch, the farther from the carrier the higher the pitch. Now if you are transmitting on 27.3848 and transmit a 2000Hz (2kHz) tone on AM you will have power going out at 27.3848 (your carrier) as well as spikes at 27.3868 (2000Hz tone on USB) and 27.3828 (2000Hz tone on LSB). On SSB the carrier and one of the sidebands audio tone would be filtered out and not transmitted. Now if he was listening at the same frequency a 2,000Hz tone would sound like 2,000Hz because it is 2,000Hz away from the carrier his receiver is generating. With him being on 27,3850 the carrier being generated in his receiver is 200Hz higher than the one used by your transmitter, as a result the frequency of the audio tones as perceived by his receiver will change. On USB the 27.3868 spike will be 1,800Hz above his receivers center frequency and sound lower in pitch, on LSB the 27.3828 spike will be 2,200Hz away from his center frequency and sound higher in pitch. If his center frequency is far enough away from yours that it puts your transmitted power outside of his receivers filter bandwidth he won't hear you at all. Or something like that.;) [SIZE=1] [/SIZE] [/QUOTE]

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