ARRL 600m Experiment Group

WD2XSH/34 Station Licensed to WRPK

Rural Indianola, Iowa   EN31fk

Ralph Wallio, WRPK     W0RPK@netINS.net

 

 

WD2XSH/34 is being developed as a portable 600m digital station for ARRL ARES message handling.

See http://www.500kc.com/ for extensive information about the much larger 600m experiment.

See http://www.500kc.com/W0RPK_Report/W0RPK_Report.htm for daily 600m activity updates.

 

 

PC soundcard software includes MultiPSK, DigiPan and WSPR.  RF output from the LP filter goes through a HeathKit HM-102 calibrated for 600m then through a KN8AZN RF ammeter sensor then a HeathKit HD-1234 Coaxial Switch with one output going to a HeathKit HN-31A Cantenna dummy load.

 

RF output is measured by the Wattmeter, RF ammeter and Tektronix 2215 Oscilloscope.

 

The WD2XSH/34 station is currently operating in a breadboard configuration.  To the left is the PSK600, a modification of a Small Wonder Labs PSK20/30/40 digital transceiver with 2W output power (http://www.smallwonderlabs.com/).  In the center is the EB63-600 linear amplifier, a modification of the Communications Concepts EB63 semi-kit with 100+W output power (http://www.communication-concepts.com/).   To the right is a DIY low-pass filter.  All of these modules were developed by Fred Temple, KN8AZN (WD2XSH/29).

 

 

 

 

The top loading coil, ~360uH, uses 14ga stranded electrical wire wound on 4in SCH20 PVC pipe with end caps.  SCH20 PVC pipe is often used for sawdust collecting systems.  Weight is roughly half of SCH40 pipe.

 

The vertical radiating element is 20ft long.

 

 

The loading coil is protected from rain and snow by a simple shroud fabricated from heavy weight plastic sheeting.

 

Four 40ft capacitive-hat loading wires are attached above the loading coil.

 

 

 

 

 

The antenna base is a modified Newtronics Hustler BTV mount using a second top insulator at the bottom.  The feed-point is shunted to ground with 11,000pF.

 

Radial wires, 32ea 40ft, are hidden in grass thatch.

 

 

Radial wires, 32ea 40ft, can be seen in this view of the portable mount which can be disassembled for transport.

 

 

The entire antenna fits into an 80ft diameter circle.  White flags are at the ends of 32ea 40ft radial wires.  Capacitive-hat loading wires, 4ea 40ft, droop to 10ft at the ends.  All of this is portable for remote ARRL ARES digital message networking.

 

 

 

 

 

 

 

 

WD2XSH/34 uses two receive antennas including a DIY 8ft amplified shielded loop,

see http://members.shaw.ca/ve7sl/burhans.html for details.

 

 

The second receive antenna is a DIY amplified whip based on an AMRAD design,

see http://www.arrl.org/files/file/Technology/tis/info/pdf/0109031.pdf for details.

The circuit has been slightly modified to use an inexpensive J310 FET and 12VDC.

 

 

WRPK Home Page