LONG DISTANCE LOCATOR, LDL's
A Long Distance Locator (LDL,) is characterized as a device operating in the Ultra High Frequencies (UHF,) 300 to 3000 MHz's. The U. S. Air Force used the frequencies from 225 to 400 MHz's. The most successful success to-date has operated in the 300 to 400 Mhz's frequency spectrum. Equipment is scares and generally one of a kind of custom built, crystal-controlled transmitter, transmitting an AM carrier wave. This information is presented for educational and informative information, and use of the equipment in the U. S. can result in serious consequences.
If any of you reading this knows of a company that makes to order transmitter kits, please use the email address at the end of the Web Page and advise us. In the U. S. it's legal to sell a kit and the assembly instructions as long as the kit is not assembled. No kit manufacturing company in the U. S. will touch manufacturing a quality kit, operating in the 225 to 400 Mhz's spectrum. However, in Europe, the Far East, Central and South America there are probably reputable kit manufactures that wouldn't think twice about manufacturing a Kit, using the Direct Digital Synthesizer (DDS) system.
The beautiful thing about operating in the UHF band is only a small antenna is required, almost stealth in nature. The device requires a transmitter and a used surplus URC-101 would suffice. The going price is around $1250.00 includes operating manual, from a surplus dealer in the U. S. A way to patch an audio signal into the microphone circuit would have to be configured using an Audio Generator, cost around $250.00 dollars, wired and tested. A 400-4 directional-beam antenna is desirable, costs around $70.00 dollars.
Another thing about operating in the LDL mode, and UHF frequency spectrum, it only takes around one half watt of power to reach nine kilometers. The directional-beam antenna has a multiplication factor of around 10. A half-watt output equals five watts on the cache end. The Directional-bean antenna needs to be aimed in a downward manner to prevent excessive RF signals. There will be enough stray RF signals regardless…we don't want Uncle Charley on your case.
For a receiver any police scanner tuning in the VHF and UHF band would do just fine. Some cache hunters prefer to use the triangulation method, to using a receiver. This is the ultimate locator to use when the general area is known to pinpoint a cache. Using the triangulation method and plotting the location on a map, will indicate anything that might prevent a direct approach i.e. a deep canyon or a residence near by.
The LDL requires two different antennas. One is an Omni antenna in resonance, with the frequencies in the 300 to 400 frequencies, and the other is the 400-4 directional-beam antenna. The Omni antenna is used to locate the signal path of the "Beacon Signal," from the antenna to the gold cache. This is accomplished by using one or two "L" rods. When operating close to a transmitting antenna an "L" rod has more than a fifty percent chance of locating the "Beacon Signal," path. Unlike the LRL, the LDL only uses one frequency for gold. A frequency of 388.4 MHz's will work, give it a try and find out for your self. Radio Frequencies (RF) switches are available for switching antennas, without having to change antenna coax.
By doing the work an LDL can be built for less than $5000.00 in U. S. dollars. Not a bad price considering the first LRL in the late 1980's cost $3500.00 dollars, and wouldn't work. Praise the Lord for the internet. There is a difference in internet and Internet. Internet is used within a state, and internet is used worldwide. There are kit companies marketing plans for building low frequencies LRL, but why fool with such elementary devices when there is no reliable documentation any have worked.