NEW PHOTOS!: Dave sent me the following in early January 2012, and I sized them for this webpage and added the captions:
WD2XFJ (ex-'PLI' ident) is now operating as an FCC Part-5 licensed high-power LowFER beacon with about 200 watts input to the final amplifier and approximately about 1 to 2 watts E.R.P. output. WD2XFJ has a repeating CW identifier (formerly) with Dave's address in Burbank in CW/A1A. Dave's ident and message varies from time to time, and sometimes there is a one-minute "blank" (gap) in the identifier for a silent period so another local DXer can receive through Dave's huge signal. (see UPDATE on the first paragraph)
NOTE: During the middle of 2009, Dave is in the process of moving location (4 blocks only), and his beacon will be off-air frequently (actually, it's been totally-off-air since summer, 2009).
(S.P. McGreevy writes: I can receive PLI, soon to be WD2XFJ, in the daytime in the Owens Valley about 150 miles away from Dave's CW/A1A beacon, which runs about 50 watts input for about 1 watt ERP. I notice that sometimes it was better strength than the "UR" NDB idents from near Burbank Airport, carrier on 253 kHz, as well as the 337 NA (Santa Ana) idents too. WD2XFJ 183.500 kHz has very noticeable skywave reception at night in the Owens Valley, California (150 mi/240 km), often reaching strengths 10-15dB over his daytime signal, especially at about 0400 local time to just as local dawn breaks. Undoubtedly, this is due to skywave/groundwave mixing and associated QSB.
WD2XFJ Antenna - close-up of the 10-20 m beam employed as top capacity-hat.
WD2XFJ Antenna feed-line pass-through into Dave's garage/shop. Dave writes: The radial wires leaving the wall are 4 counterpoise radials that are 70 feet long and about 10' above ground. My garage is in the center of the yard so the radials feed in opposite directions to the corners of the property. The property is built on a hillside over an old riverbed with very poor ground. These radials work extremely well at overcoming the shortfalls of a poor ground when used with a balanced tuner for 160-40 Meter operation has been verified by other local stations that over 20 dB of signal improvement has been obtained using the tuned counterpoise arrangement in comparison to 6: 8' ground rods and radials in the yard. It's also a whole lot easier!
1. VARIOMETER. This picture shows my adjustable variometer that has an Inductance range of 2mH to 6mH. It's "Q" is over 700, and is wound using 200 strand, #40 Teflon coated litz wire. The telfon coating is when using hi Voltages, and can be purchased by Kerigan Lewis in Chicago, Ill. The basic design shown uses a 6" diameter, and 5" diameter Plexiglas forms. A newer design currently in the works would use a DC motor to adjust the inside coil for remote tuning.
2. ART-13 TRANSMITTER. This transmitter is excellent not only as a ham transmitter for AM and CW, but when using the low frequency plug-in will also transmit 150 Watts of carrier down to 200Kc. It is easy to pad the oscillator and make it work through the 1750 Meter band (160 - 190 kHz). I have tried this with the transmitter shown with outstanding reception reports over 100 miles away on AM. It works very well on CW and MCW. An external Pi-network is required as the 803 plate final goes to an external binding post via a DC blocking capacitor. The power supply is also external and provides 1200, 400, and 28 Volts. Building a power supply for this makes it a big project!
The WD4PLI / WD2XFJ lowFER station operating position above
WD2XFJ 183.5 kHz lowFER station transmitter
On 20-21 August (at sunrise) I have been doing initial field-testing of the WD2XFJ LF Receiver using both its own whip antenna (seen in the photo) and an outboard (mid-80's era) Burhans J-310 Active whip antenna system with 1.3 meter tall whip antenna.
During the tests 2.5 miles (4 km) away from my Owens Valley, California home, I operated my own LowFER (CW/A1A) beacon "OL" on 185.41 kHz. I run this "OL" beacon intermittently and during DXpeditions only).
Initial tests show excellent sensitivity especially with the external J-310 active whip. I've been able to also catch lowFER SMV in Simi Valley, CA on about 186.58 kHz which is about 150 miles to my south, and my local LF beacon causes desensing of Dave's receiver due to high field-strength from it 2.5 miles distant. This very portable receiver has been a joy to use, and I want to try to catch a couple of Siberian/Russian LWBC stations with it before 1300 UT sign-off of Radio Rossi. The receiver has a pre-selector as well as other controls (as seen in the photo) and operates in LSB mode approx. 160 - 190 kHz.
A heap of GREAT information about 1750 meter transmitting antennas (1.6 mb PDF). Enlightening reading about LF vertical antenna and grounding systems.
WD4PLI/WD2XFJ Active-Antenna/Phasing Receiving System - very low-noise capabilities (and more shots of Dave's vintage receivers)
Interesting Three-tube transmitter article for the 1750-meter 'Neglected band' that Dave supplied, written in January 1972.