The Utah
AmateurRadio Club:
Doppler antenna
arrays
PLEASE NOTE:
THISPAGE IS UNDER CONSTRUCTION!
IF YOU HAVE ANY
SPECIFIC QUESTIONS, USE THE EMAIL INFO AT THE BOTTOM OF THE PAGE
Jacques Brodeur, VE2EMM has designed a microprocessor-based
"doppler"type DF unit described at VE2EMM'sMontreal
Doppler II page that drives the antenna switching
circuit,updates the display, and does signal processing to determine
the bearing. This unit works along the same principles that the
so-called "Roanoake"DF units do - but the addition of a microprocessor
(to do the generationof switching signals and processing of the
received audio) adds additionalflexibility.
Please refer to VE2EMM's
web page for detailed information about the theory and operation
ofthe Montreal Doppler II unit.
The antenna array:
THIS TEXT IS UNDER CONSTRUCTION
A few handy links
toDF equipment you can build and/or buy:
- At this site, there are the WA7ARKcircuits.
These are "homing" circuits as described abovethat provide a
"right/left" indication.
- Also at this site is described AnOffset
Attenuator - Use this circuit to reduce the
apparentstrength of the signal you are seeking when it is otherwise so
strong thatit always "pins" your S-meter.
- The venerable Roanoke Doppler is described in the book
co-authored by JoeMoell, Transmitter
Hunting: Radio Direction Finding Simplified. Information
about circuit boards and parts lists may be obtained at KB6DOL'ssite.
Circuit boards are also available from FarCircuits.
Note: Neither of these sources supply complete kits, so it
will be largely up to you to find and locate partsfor these units.
- As mentioned previously on this page, Jacques, VE2EMM has put
togetherseveral circuits of interest to the DFer and they are described
here (scroll
down to see the english-language links.) These projects
includevarious transmitter controllers for the "fox" itself as well as
severalmicroprocessor-controlled direction-finding units - including
the one describedon this page. Far Circuits
provides circuit boards, the microprocessor and afew of the
harder-to-get parts for these devices.
Note: Neither the author or UARC officially
endorseany vendors mentioned above. The level and satisfaction of
performanceof any of the above circuits is largely based on the skill
and experienceof the operator. Your mileage may vary.
Do you have any DF-related questions? If so, you may send
emailto the address below:
 |
Do not click on the address above
- simply typeit into your email client
Go
tothe UARC DF page or go to the UARChome page
This page updated on 20031126