Presently, amateurs in The Netherlands are really happy, not only have we got the permission to transmit on 4m, we also may transmit on 600m again. For the time being between 501 and 505kHz.
For this range (well, to the upper QRG of 504kHz) this article could lead to a cheap signal source.
However, in about a month's time, we will know is we need to redesign our exciters, i.e. to the range 472 to 480kHz. So, lets have another look at the cheap crystal solution.
The new range is not that easy really. One solution would be the mixing of two standard xtal frequencies:
- 4915.2 - 4433.6 = 481.6 somewhat high, could be pulled into the range
- 9830.4 - 28060/3 = 9830.4 - 9353.3 = 477.1
- 7030 - 6553.6 = 476.4
- 14745.6 - 14270 = 475.6
- 7025 - 6553.6 = 471.4 (pull!)
- 3550 - 3072 = 478
- 4000 - 3530 = 470 (pull!) (*)
- 3555 - 3072 = 483 (pull!)
Mind you, the higher the frequencies, the easier to pull, i.e. create a nice tuning range. However, lower frequencies will give better stability.
(*) Note, there is a 4.00MHz ceramic resonator, which will allows for a nice VFO. Use a Pierce oscillator to obtain a QRG above the ceramic resonator's series resonance.