About the KFS WebSDR Server

Technical Details History of KFS Donate Operating Tips Propagation Observations Contact


Technical Details of the system:

The KFS WebSDR HF radio server system is located near the mouth of Lobitos Creek on the Pacific coast, six miles south of Half Moon Bay, California, USA. This RF quiet location, on a 150 foot cliff overlooking the Pacific Ocean, is in maidenhead grid square CM87tj02; the geographic coordinates are 37° 23' 6'' North, 122° 24' 45'' West. You can easily locate the site using Google Maps or Google Earth by searching for KFS WebSDR.

The four TCI antennas at the site are connected with multicouplers to a house RF distribution system that provides signals to all users. All but one of the WebSDR receivers are connected to the Omni antenna, a TCI Model 530 Log-Periodic Antenna (omni, 6 dB gain, 3-30 MHz). The antenna for the 40ph band is switched between the usual Omni and the SE Sector antenna, a TCI Model 527B Log-Periodic Antenna The other two TCI 532 LP antennas (NW Sector and NE Sector) are not use by the KFS WebSDR at this time. Pictures of the antennas, courtesy of Hal, KK6HY, are here. The individual receivers are FiFi SDR receivers with internal sound card chips, in a custom rack mount chassis. The 160 meter receiver is preceeded by a KD9SV Products SV-160 160 Meter Preamp, modified for rack mount, to compensate for the antenna response. Antenna and rack space facilities are provided as a public service by Globe Wireless Radio Services.

The server computer uses an ASUS Z170 motherboard in a rack mount case with 8 GB of RAM, and a 120 GB solid state drive; it runs the Debian Linux operating system. The Internet service provider is Coastside.net in Half Moon Bay. WebSDR server software was written and is maintained by Dr. Pieter-Tjerk de Boer, PA3FWM. Pieter maintains a list of active WebSDR servers and a FAQ page.

To view the system maintenance log, click here. The system operator (Sysop), Craig, W6DRZ greatly appreciates the technical assistance provided by Bob KO6AQ, Steve W7RNA, Paul W7JVY, Hal KK6HY, and Ken WB6CNI. Also appreciated are the donations by many users. Comments and questions are always welcome. Please email Craig.


History of KFS:

The KFS story begins with the Beach Station (Ocean Beach), which was put into operation in July 1910 by the Poulsen Wireless Telephone and Telegraph Company. The Beach Station was located just north of the San Francisco zoo at 48th Avenue and Noriega Street.

The Dollar Steamship company formed DOLLARADIO in 1929 (in 1930 becoming Globe Wireless) to handle their ship-to-shore communications. Dollar's first shore station was constructed at Mussel Rock about 15 miles south of San Francisco near the north end of of Pacifica. Eventually, Globe opened their facilities to the public and to communicate with ships of any line.

The 200 acre Half Moon Bay facility on the coast near Lobitos Creek, LO, was constucted in 1932 by the Mackay Radio and Telegraph Co. as the receive site for maritime radio station KFS and point-to-point station KTK. (The transmit site for KFS and KTK, MX, was established in the Palo Alto bayland marsh.) Operations from Ocean Beach and Mussell Rock were all moved to the new facilities. The International Telephone and Telegraph Company (ITT) subsequently purchased the stations and operated them for many years. Eventually, in the early 1990s, ITT sold KFS (KTK had ceased operations) to a group of local investors. These investors also obtained, from the Tropical Radio and Telegraph company (TRT), station WNU near Slidell, Louisiana and, from the United States government, the former Voice of America sites near Dixon, California. This was the beginning of a modernized HF network, reusing the name Globe Wireless.

The last commercial radiotelegraph transmission in North America was keyed from LO and transmitted from MX at 2359 UTC on July 12, 1999. The final words transmitted by KFS? "What hath God wrought". By the turn of the century, the Half Moon Bay facility had become the central control, database server farm, and west coast receive site for the Globe Wireless HF data and email network providing GlobeEmail and GlobeData services to 40,000 commercial shipping vessels from stations at 23 worldwide sites. When Inmarsat purchased Globe Wireless in December 2013, the HF portion of the operation was retained as Globe Wireless Radio Services.

Craig, W6DRZ, a former Globe Wireless executive installed a WebSDR system at KFS in February 2016, initially named LO WebSDR and renamed to KFS WebSDR in January 2017. The system is on its second set of computer and receiver hardware and enjoys support from the HF listening community. Currently, the KFS site is also in use by HF radio providers serving the aeronautical, emergency response, and military communities.

The February 2018 edition of Electric Radio magazine published an article entitled The KFS Story on page 2 with a nice cover picture of the building. It was authored by Gary, K6GLH, with help from Craig, W6DRZ, and adds more detail and pictures to the above brief account.


This WebSDR system is provided as a community service by Palomar Park Radio. Your contribution will help offset our operational costs.
Any and all support is appreciated. Thanks & 73, Craig, W6DRZ


Operating Tips for the KFS WebSDR:

- Newer browsers with HTML5 support like Chrome, Edge, Firefox, and Opera will work best. Older browsers, including Internet Explorer, need both Java and JavaScript enabled for WebSDR to work properly. For details, click here.

- You can specify the startup frequency and mode in the URL when linking to the KFS WebSDR. Use the ?tune= parameter, for instance http://69.24.184.62:8901/?tune=7293am to listen to 7293 kHz in AM (40M AM window).

- Please enter your call sign or name in the box near the top; do not add additional comments. The user display will be much more informative.

- The orange labels under the waterfall are changed twice a day, and are different on weekends, to keep them timely. Suggestions for additions and changes are welcome.

- In addition to the above, you can save your frequency, mode, and bandwidth settings with custom memory labels (green); set them up in the Memories: box.

- Click on any label to tune to that frequency and mode, or just click on the frequency scale under the waterfall. You can drag the waterfall to the left and right with your mouse; the mouse wheel zooms in and out.

- Note that the waterfall view also offers a spectrum (panadapter) display, select it in the View: dropdown, in the Waterfall view: box.

- Are the waterfall labels missing, or wrong? An easy fix is to click on the very right end of the active waterfall. Clicking on max out in the Waterfall view: box also resets the labels.

- West coast users may want to try the W7RNA WebSDR in Sedona, Arizona as an alternate system for certain signals.

- If the page appears to freeze, I may have had to restart the WebSDR server. Just hit refresh on your browser to resume.

- There is an idle timeout set to sixty minutes. If you don't use the system for that long you will be disconnected.

- To conserve our shared internet bandwidth, one connection per user, please. When you are finished using the system, please disconnect by closing your browser. Thank you.


Propagation Observations using the KFS WebSDR:

I have always preffered to observe propagation, rather than to predict it. With that in mind, here are some ideas using the KFS WebSDR:

80 Meters: In the evening, to see if the band is open from California to the US east coast monitor Gander Radio VOLMET (VFG) on 3485usb at 20 and 50 minutes past each hour. Note that New York Radio VOLMET (WSY-70) is also supposed to be on this channel, but is reported off-the-air until June.

80 Meters: In the morning, to see if the band is open from California to Asia monitor Beijing VOLMET (BSQ) on 3458usb at 15 and 45 minutes past each hour. Guangzho VOLMET (3UW-33) is assigned the other time slot on this channel. Also, Goyang NIS broadcasting from North Korea on 3480am is usually available.

40 Meters: In the morning, to see if the band is open from California to Asia try the Russian Navy Beacons from Petropavlovsk Kamchatskiy. The K beacon is most often reported - on 7039.5cw - however can be hard to hear with interference from US hams.

20 Meters: Monitor 14100cw for the Northern California DX Foundation worldwide beacon network, available 24-hours per day. Details are at NCDXF beacons.

Other?: If you know of any other 24-hour stations that can be received by the KFS WebSDR Please email Craig.