Motorola DTMF signaling

[seandeely]

Hello I am new here so if this is the wrong forum to ask let me know where I can go. We'll start with the background information, I work for a small railroad that uses radio activated crossings. On our line we have 9 crossings with unique DTMF codes for activating and deactivating the gates lights and bells, so we're talking 18 different codes. Our locomotives have cab radios with the codes stored under the street name (Main St. - UP, Main St. - Down) while on our main channel we can cycle through the list of codes and then tone up and down those codes as we approach the crossings. we have an aging fleet of Kenwood portables that are also able to do this, but we want to shift over to all Motorola products. Our newest radios are the CP200D radios from Motorola and for ease of maintenance, charging, accessories etc we were looking to acquire the CP200XLS models since they share the same battery, antennas, mics and so on. Will we be able to have the list of crossing tones programmed in? We understand that the CP200XLS and CP200D are discontinued however we have no need for the newest most expensive radios Motorola has to offer. Would the CP100D have this functionality, would the HT1250 be another good refurbished option? Do we need a full keypad or will a limited keypad do the trick? We are not Motorola technicians, programmers or salespersons we just want an answer from someone who knows and doesn't want to up sell us space aged technology.

 

[jrothwell]

I don't have the answer, but this seems like a security/safety risk. Anyone could intercept those tones and replay them, causing serious traffic and safety issues.

 

[seandeely]

I don't have the answer, but this seems like a security/safety risk. Anyone could intercept those tones and replay them, causing serious traffic and safety issues.

railroads all over the country use DTMF signaling for switches, crossings, signals, EoTDs etc.

 

[jrothwell]

railroads all over the country use DTMF signaling for switches, crossings, signals, EoTDs etc.

Wow, ok. That seems crazy.

 

[RFI-EMI-GUY]

There used to be a bunch of companies who manufactured DTMF encoders for land mobile radio. There may have been something of an autodialer that would do this. Your application begs for some control automation such as a GPS directed look up table to preload the intersection into the display. Then you could avoid mistakes before sending the tones. EDIT I missed that you need only 9 crossings and use portable radios. Some Motorola radios do provide an autodial feature that may work, provided it also allows alpha tags.

 

[wa8pyr]

Hello I am new here so if this is the wrong forum to ask let me know where I can go. We'll start with the background information, I work for a small railroad that uses radio activated crossings. On our line we have 9 crossings with unique DTMF codes for activating and deactivating the gates lights and bells, so we're talking 18 different codes. Our locomotives have cab radios with the codes stored under the street name (Main St. - UP, Main St. - Down) while on our main channel we can cycle through the list of codes and then tone up and down those codes as we approach the crossings. we have an aging fleet of Kenwood portables that are also able to do this, but we want to shift over to all Motorola products. Our newest radios are the CP200D radios from Motorola and for ease of maintenance, charging, accessories etc we were looking to acquire the CP200XLS models since they share the same battery, antennas, mics and so on. Will we be able to have the list of crossing tones programmed in? We understand that the CP200XLS and CP200D are discontinued however we have no need for the newest most expensive radios Motorola has to offer. Would the CP100D have this functionality, would the HT1250 be another good refurbished option? Do we need a full keypad or will a limited keypad do the trick? We are not Motorola technicians, programmers or salespersons we just want an answer from someone who knows and doesn't want to up sell us space aged technology.

Why aren't there any track circuits to automatically activate the crossing protection? Not too tough to do, in it's most basic form all you need is four insulated joint bars for each crossing and wire the signal hardware to the rails.

That being asked, I think that the HT1250 has call list memories for this sort of thing. Ditto the CP200XLS. However, it's been awhile since I worked with either one and I'm not 100% sure.

UPDATE: From the product brochure for the CP200XLS full keypad model:

Radio Call
Initiate Quik-Call II and/or DTMF Call Alert
or Selective Call Encode from a call list

So yes, it can be set up with a DTMF call list.

 

[seandeely]

Why aren't there any track circuits to automatically activate the crossing protection? Not too tough to do, in it's most basic form all you need is four insulated joint bars for each crossing and wire the signal hardware to the rails.

That being asked, I think that the HT1250 has call list memories for this sort of thing. Ditto the CP200XLS. However, it's been awhile since I worked with either one and I'm not 100% sure.

UPDATE: From the product brochure for the CP200XLS full keypad model:

Radio Call
Initiate Quik-Call II and/or DTMF Call Alert
or Selective Call Encode from a call list

So yes, it can be set up with a DTMF call list.

there are track circuits but we have crossings very close to our yards and stations so the islands are very short to accommodate the train sitting close to the crossing. thank you for the information.

 

[JustinWHT]

It would seem easier to print the crossing names and DTMF codes and laminate the cards. Attach to convienant spot with 3M outdoor double sided tape.

 

[JustinWHT]

I don't have the answer, but this seems like a security/safety risk. Anyone could intercept those tones and replay them, causing serious traffic and safety issues.

DTMF Deactivate signs

About a month ago, before the recent unpleasantness started, I spent a few hours looking at every part of the Grafton and Upton RR visible from public property. Looking back over some photos today I was reminded of something I'm curious about. In two places I noticed blue signs with the text...

forum.mrhmag.com