Tuesday, September 1, 2009

U.S. 40m QRSS XTAL combi

On the KnightsQRSS-list, recently a discussion about frequencies went on. Stu and Dave pointed out frequency restrictions of various license categories. QRSS transmissions have been done on 7.105MHz, as far as I recall.

Using an appliance, one can set the rig to any random frequency, agreed, operating an MEPT homebrew-style, here are two options:
  • 7.106 = 10.106 - 3.0
  • 7.103 = 12.288 - 5.185
The 5.185MHz crystal used to be on a distributor's list I printed in May 2009, the same distributor appears not to be selling this crystal any longer. The crystal is still listed at DigiKey.

There is a somewhat more difficult approach however which would involve penning down crystals:
  • 7.105 = 11.0592 - 3.9542 (1.)
  • 7.105 = 11.000 - 3.895 (2.)
  • 7.105 = 9.202 (3.) - 2.097152
With:
  1. penned down 4MHz crystal
  2. penned down 3.9321MHz crystal
  3. penned down 9.216MHz crystal
I hope this helps to promote the idea of QRSSing at frequencies accessible to all.

73, Joachim