 |
Re: CLIFF EFFECT issue??? - BNSF To Begin Digital Radio Frequency Testing
Author: SLG
Date: 08-23-2011 - 16:33
There's your problem, the railroads do not comprehend, nor do they sufficiently test new technologies before deploying them. When all hell breaks loose is when they discover trouble for the first time and the employees in the field are left to fend for themselves. As described here, this so-called cliff effect of digital is going to get some railroaders killed. Mark my words. It will happen. You must realize the railroads are inept at maintaining their analog radios in their current form because of understaffing and incompetence among telecom departments.
Trainmen working a long freight train with obstructed line of sight rely on the audio quality of analog transmissions to know if they are getting out of range from the locomotive and vice versa. A scratchy, noisy signal is a sign to change positions, hold the radio up higher, stop the movement, etc. It's a warning buffer that gives the train crew or MOW employees an opportunity to rectify the situation. No such luxury is afforded by digital radios.
Fan boys of digital are quick to point out digital audio quality is up to 20% "improved" at weak RF signal strengths over analog transmissions. This is no consolation to the conductor or brakeman 10,000 feet from the locomotive riding a moving cut of cars who have NO IDEA if a radio transmission will suddenly become too badly degraded because of the aforementioned cliff effect. Depending on user locations, terrain, radio/antenna condition, and other factors, other employees listening for a response might not hear anything at all. Just because everything worked fine and dandy ten seconds earlier means absolutely nothing. This scenario is exacerbated by an INFINITE number of possible transmit and receive locations between conductor/brakeman/engineer and the train dispatcher or other employees.
Another area of concern is with the funding for digital voice. Government agencies have deep pockets for their digital voice systems thanks to you, the taxpayer. The private sector is obviously much different and the railroads are no exception. I know of many instances where it's taken YEARS to fix defective radios because no funding was available.
As long as this mindset is permitted to promulgate within the railroads, digital voice will fail miserably and the history books will be written in blood...
Trainmen working a long freight train with obstructed line of sight rely on the audio quality of analog transmissions to know if they are getting out of range from the locomotive and vice versa. A scratchy, noisy signal is a sign to change positions, hold the radio up higher, stop the movement, etc. It's a warning buffer that gives the train crew or MOW employees an opportunity to rectify the situation. No such luxury is afforded by digital radios.
Fan boys of digital are quick to point out digital audio quality is up to 20% "improved" at weak RF signal strengths over analog transmissions. This is no consolation to the conductor or brakeman 10,000 feet from the locomotive riding a moving cut of cars who have NO IDEA if a radio transmission will suddenly become too badly degraded because of the aforementioned cliff effect. Depending on user locations, terrain, radio/antenna condition, and other factors, other employees listening for a response might not hear anything at all. Just because everything worked fine and dandy ten seconds earlier means absolutely nothing. This scenario is exacerbated by an INFINITE number of possible transmit and receive locations between conductor/brakeman/engineer and the train dispatcher or other employees.
Another area of concern is with the funding for digital voice. Government agencies have deep pockets for their digital voice systems thanks to you, the taxpayer. The private sector is obviously much different and the railroads are no exception. I know of many instances where it's taken YEARS to fix defective radios because no funding was available.
As long as this mindset is permitted to promulgate within the railroads, digital voice will fail miserably and the history books will be written in blood...
