This Permability Tuned Oscilator Kit for 160-20 meters gives flexability
to your radio projects.  It will tune over a wide range 200 kc to 500kc depending on band. 
About 13 kc per revolution of the tuning dial.  You can add this to your simple transmitter or direct
conversion receiver and not be rock bound.  Manhatton style PTO  for  $21.95

This PTO can be trimmed down to fit into a very small place.
Those are 1/4 watt resistors and a 6-32 thread for size.