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The Kalleda Photo Project is up and running again. The new photobloggers are students at Pai Junior College, beside Kalleda Rural School where the project started in 2005. The new teachers are Alma Carver and Lane Goodman, both students at Washington Univ., and members of this year's Village India Program.
This is group #2, composed of 2nd-year students at the school (mostly 17 years old).
German built, as most German built RDF sets, very good.
type PE1026
gyro coupled, fully automatic
frequency bands
224 kHz - 538 kHz the white outer scale,
blue sub-scale is bandspread for the ranges
285-325, 405-415, 490-510 kHz
1600-4299 kHz
the art of Radio direction finding.
the very first system of radio navigation was the Radio Direction Finder, or RDF.
In use by the military, (counter)espionage, navigators in ships and aircraft.
By tuning in a radio station and then using a directional antenna, one could determine the direction to the broadcasting antennae.
A second (or 3rd) measurement using another station(s) was then taken.
Using triangulation, the two (or three) directions can be plotted on a map where their intersection reveals the location of the navigator.
Commercial AM radio-stations can be used for this task due to their long range and high power.
Strings of low-power radio beacons were also set up specifically for this task, especially along coasts, near harbours and airports.
Early RDF systems normally used a loop antenna, a smal loop of metal wire that is mounted so it can be rotated around a vertical axis.
At most angles the loop has a fairly flat reception pattern, but when it is aligned perpendicular to the station the signal received on one side of the loop cancels the signal in the other, thus producing a sharp drop in reception.
This is known as the "null"
By rotating the loop and listening for the "null" , the relative bearing of the station can be determined.
Loop antennas could be seen on most pre-1950s aircraft and pre-1990s ships.
Burning the effigy of Ravana, at the Dusshera Festival in Annaram village near Kalleda. Dusshera commemorates the victory of Lord Rama over Ravana, and the victory of good over evil. Photo by the talented kids of the Kalleda Photo Project.
RDF Junior Command and Staff Course graduates from RDF Command and Staff College | Musanze, 24 March 2023
The Kalleda Photo Project is back in business: the new photobloggers are 16-18 year old students at Pai Junior College, Kalleda, Warangal Dist., A.P., India.
This shot of a village carpenter is by first-year student Ragu.
Detail of the Microsoft-branded RDF bag. Microsoft supported RDF until the browser wars with Netscape.
Students dancing as Gods Krishna and Gopikalu. Taken by Suresh, one of the kids in the Kalleda Photo Project.
Women at a pooja (religous ceremony) in honour of the birthday of lord Sri Ram of Babri Masjid fame. Photo by Ravikumar of the Kalleda Photo Project.
RDF Assessement Training Ex in Glen of Imal including avisit to troops by Maj Gen Ralph James DCOS ops
The Kalleda Photo Project is back in business: the new photobloggers are 16-18 year old students at Pai Junior College, Kalleda, Warangal Dist., A.P., India. This study in subtle colors is by Karthik.
The Kalleda Photoblog kids have started teaching photography to a new group. This image of a toddy tapper was taken by Anil, one of the new photographers.
Srikanth climbs down into the well. Photo by Ravikumar of the Kalleda Photo Project, Andhra Pradesh.
Creating entity, import RDF Schemas, make link (relationship) with dragging, add entities of the same relationship at once.
RDF Officers and Other Ranks conclude multinational military exercise in Kenya | Nairobi, 17 March 2022
Another image of daily life in an Indian village: "cleaning the feet of the god" by Karnakar of the Kalleda Photo Project.
The Kalleda photobloggers are recording the progress of the new Pai Junior College in a series of shots from the highest accessible point on the roof of the Kalleda Rural School. The "Pai in the Sky Cam" showing progress on the construction of RDF Pai Jr College is now available on its own account at http://www.flickr.com/photos/paicam
The little guy on the left as you look at them (with the pink hair and blue outfit) arrived the other day! I am trying to get two of each of the RDF animal trolls (Dog, Cat, Mouse & Ape) again! Just need another dog now I have my second cat, to have two complete sets! There is no hope for me! LOL! ;O)