|See also the 2m/145MHz version.|
Tested by PA0DFN for use in Dutch ARDF
Fully ANALOG design.
Fully balanced input : antenna + buffer + mixer.
Small, cheap internal ferrite antenna.
RF-filtered headphone output for accurate minimum bearings.
Very sensitive : during evening time the galactic noise is detectable.
Very selective (Xtal IF filter + hi-Q if coils).
Large sensitivity adjustment range (>= 90dB)
Positive, and adjustable sense action.
Only 18 to 35 mA current consumption (varies with the gain adjustment).
Stable reception until a 9V battery is really empty (5.5V).
Detailed component list with ordering numbers.
Detailed construction and adjustment texts.
Cheap and light ABS housing.
Easy to fill double sided RF designed PCB with wide holes. PCB 135x39mm
Coil forms for winding coils yourself :
DO SAVE and PRINT all the files below, as for this version valid
Study all info before you start to build.
|Ferrite- and sense antenna||Details of coils||Assembling||Drill plan||Setup|
Older 80m prototype.
2m version build by PA0ADG.
Developments in time.