EMRFD Message Archive 11234
Message Date From Subject 11234 2015-06-22 19:43:34 bob_ledoux Altering Crystal Frequencies Back in my younger days I used to grind and polish FT-243 crystals to a desired frequency. I'd also put soft pencil lead spot on a crystal face to alter the frequency.
There are lots of web pages that discuss these processes.
The FT-243 has four screws to remove the cover to access the crystal element. Here is a more recent effort:
Hack Your Crystal’s Frequency