Railfan Technology > Detectors, functions and classification.

I have found RR Defect Detectors to be of considerable benefit and would be grateful to know of a directory of defect detectors and the functions each one performs.

Failing that, I'm inclined to compile and share a listing of detectors but would need to know the protocol used to define the different functions.
I've heard detectors announce the temperature, give axle counts and indicate which track is being reported as well as the direction of travel and
speed.   Are there specific codes used by the signal maintainers to indicate what each detector does?

A hypothetical example of a detector listing:

RR   MILE         FREQ    AAR FUNCTIONS
NS MP 317.8   160.800 046    D2, TR
        D2 = ANNOUNCES ON DEPARTURE 2 TIMES
        TR  =  ANNOUNCES TRACK NUMBER

Another hypothetical example:

ABCD MP909.8 160.215 007   A-D AX TR F C
A reports on arrival of train
D reports on depature of train
AX reports axle count
TR reports track number
F  reports temperature
C reports direction of train

What I think is most important is that there is a general agreement on what code each function is assigned and that it conforms to the format  (if any) used by
signal maintainers.

I solicit advice, counsel, words of wisdom, suggestions and intelligent critique.

Be Well,

Tim Colbert  K3HX




 

Interesting project, Tim.  I wish you had announced this about two weeks ago.  I rode the Cardinal between Cin and WAS and I could have made some notes along the way.  I have some information on some roads with MP locations but not what they report.  If you decide on a format, I'll see what I can do to assist you.  I know there is some information on most of the Amtrak routes west of Chicago but I'm suspecting you are more interested in Eastern Railroads.  If you do want the west information I'll look it up for you.  I think it only has the MP and frequency information listed.

73's  John
 

The Steam Powered Video railroad atlas books show detector locations but I don't know how current it is.

Victor A. Baird
hittp://www.erstwhilepublications.com



Edited 1 time(s). Last edit at 07/30/15 12:02 by wabash2800.

Not to throw a monkey wrench into a great idea, but some detectors are Talk on Defect only.

Checking the Yahoo group ATCS Monitor will give you loads of detectors.  They are usually listed by milepost, but you won't find out what specific functions they perform.

I have noticed that since UP took over the SP line threw Oregon,
the detector at Shed,Or. is silent.........Swede........Albany,Or.

A few things I've learned from publishing or proofreading the Altamont timetables:

-- The railroads' own lists and databases of detectors are nowhere near accurate.  The timetable listings are closer to reality, but even so...

-- The detectors we regularly hear on the radio make up probably 30-40% of the total number of detectors in service.  The rest talk on defect only or don't broadcast a radio message at all.  Instead, they cause block signals to drop to red, activate flashing colored lights, or send messages to a place like Fort Worth or Omaha where someone analyzes the data and contacts the train, if necessary.

-- Some divisions are hostile toward talking detectors due to the radio congestion they create.  As a result, some BNSF subdivisions now have ZERO detectors that talk unless a defect is found.  On the BNSF transcon west of the Colorado River at the AZ/CA border, there are two talking detectors remaining.  That's it, just two that talk regularly.