Ham Radio

[pwdrive]

You could try building a simple Ham receiver by using a regenerative design, the Hartley osc is well suited to that, one end of the grid tank coil is connected to HT-ve (ground) the other end is connected to the grid via the usual grid leak arrangement and the cathode is connected to a tap on the coil, the tap should be towards the ground end, experimentation is sometimes required for the tap position in order to get the best results, the screen grid would be connected to a variable potential divider (pot) varying the screen grid voltage varies the amount of regenerative feedback, audio output is via the anode load as usual, for AM reception then just below the point of oscillation is best, for CW or SSB reception then just above the point of oscillation is best, lots of designs on the web, an excellent set up so far as regens go is the Regenerodyne type with an RF stage, the tuning rate is constant across any band with that set up, you can either build a VFO for osc injection or alternatively use a an ordinary service type RF signal generator if it has enough output level.

Lawrence.