![]() ![]() Typically in the CB mode for USB a mixing frequency at 34 MHz was used and for LSB and AM 19 MHz was used as the Local Oscillator. Thus the mixing process in receive and transmit was shifted to LSB or USB depending on whether the Local Oscillator was above or below the Intermediate Frequency (IF). To switch between USB and LSB, in lieu of using two crystals, injection Frequencies 7.8025 MHz above and below the desired operating frequency are generated. One popular SSB generation scheme used by many manufacturers was to employ a 7.8 MHz Crystal Filter and the carrier frequency was generated at 7.8025 MHz which typically gives an Lower Sideband output when used in an additive mixer stage. Typical frequencies for the banks of crystals were in the 11 MHz range for the bank of six and in the 7 to 8 MHz range for the bank of four. Interestingly the first three crystals in the bank of four are separated by 10 kHz but the last channel is 20 kHz. ![]() Then the second crystal in the bank of six is mixed in succession with the four crystals to give channels 5 to 8. The bandswitch is arranged so that the first crystal in the bank of six is mixed with the four crystals in succession so that at initiation that would give channels 1 to 4. The typical crystal synthesizers uses two banks of crystals arranged in a bank of four and bank of six arrays. With crystals that raised the possibly to utilize commonly available inexpensive Computer Crystals to move the frequency to 10 Meters. After digesting those inputs I chose to look at the 23 Channel units since many of these radios use Crystal Synthesizers. I received many helpful inputs and suggestions. There are also beam antennas but those require a bit more work and will also require a means to rotate the antenna since they are directional, so I don't think a beam is what you're looking for.Untitled Document Conversion of SSB CB Radios to 10 Meter QRP OperationĮarly in 2009 I posted an inquiry on the QRP-L Reflector about any and all that may have converted SSB CB Radios to 10 Meters. But the 3/4 wave antenna will probably require at least two people. An Antron or Imax can probably be installed by yourself, I've done it. The 3/4 wave antenna will work very well, but it is bigger and a bit heavier than the Imax or Antron. If you aren't concerned about the looks or what the neighbors think, you might want to consider a 3/4 wave antenna. Either one of them will get you out probably 15 miles or more if installed 30 to 40 ft above pending on how many and how high the hills are around you. I believe both of them are half wave antennas. They're fairly inexpensive and easy to install. Probably the most popular, or most widely used, antennas are the Antron A-99 or Imax 2000. A 1/4 wave will perform well if installed high enough, but a 1/2 wave will perform better than the 1/4.as a 5/8 will perform better than a 1/2 and 3/4 will perform better than a 5/8. There are 1/4 wave (9 ft), 1/2 wave (18 ft), 5/8 wave and 3/4 wave (21 ft) antennas out there. Some people think that longer is better.and that is true, but the length also has to be resonant which means it has to be some fraction of a wavelength. I'm not sure what you mean by length of antenna.
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