MRCN 500 kHz Experiment Web Page

Commissioned: 1905 UTC 23 October 2009

Location: Wireless Hill, Newfoundland and Labrador, Canada (GN37)

Centre is the class E TX designed using Alan's (G3NYK) spreadsheet. (See July 2005 QST) On the board to the left are the PIC, DDS chip and keyer/driver stages. Next is the fan and the drain choke. The efficiency is rather poor although substantially better than a good class AB - this is due to a mushy driver stage (I think!) The heat sink holds the IFR640 final. ($0.80 each!) The TX is keyed with the Admy. Patt No 7681 key for CW or an 8088 PC for QRSS.

RX: The receiving setup comprises a Marconi XH100 with an AD9851 DDS HFO driven by the serial port. ARGO (FFT) and audio recording software are used. A National LF10 preselector is used as a front end and feeds an SBL-1 mixer of the XH-100.

Aerial: 100 metres of 2mm copper wire. To tune the aerial on 500 kHz about 50 uH was required, which seems quite low. The aerial exits from the helix hut via a feedthrough insulator, and extends 100 metres up the side of the hill at an average height of about 10 metres.