Amongst other things the Miller effect also needs to be taken into consideration, I don't know if your familiar with the Miller effect, in basic terms the control grids input capacitance as seen by the tuned circuit is in effect multiplied by the Miller effect, the higher the gain of the valve the higher that capacitance will be, in your design you have a pentode as the RF amp, the miller effect in a pentode will be less due to the effect the screen grid has, in the triode regen detector it will be significantly higher because there's no screen grid.
Ganged tracking for RF stages isn't always that straight forward, the resonant frequency of the two tuned stages needs to be matched as the tuning gang is rotated through it's full swing, anything less and the signal will suffer.
The RF Peak (aka RF Trim or Antenna Trim) capacitor is quite common with homebrew regens with an RF stage.
If you are into Regens you might want to have a go at one using the Regenerodyne type of circuit, with that type the Regen detectors tuning range and tuning rate is constant between different band ranges, a definite advantage if you are into SWL.
If you're interested in a schematic for a Regenerodyne type that I built then I'll dig one out.
Lawrence.
Ganged tracking for RF stages isn't always that straight forward, the resonant frequency of the two tuned stages needs to be matched as the tuning gang is rotated through it's full swing, anything less and the signal will suffer.
The RF Peak (aka RF Trim or Antenna Trim) capacitor is quite common with homebrew regens with an RF stage.
If you are into Regens you might want to have a go at one using the Regenerodyne type of circuit, with that type the Regen detectors tuning range and tuning rate is constant between different band ranges, a definite advantage if you are into SWL.
If you're interested in a schematic for a Regenerodyne type that I built then I'll dig one out.
Lawrence.
