TRAINS/CHNL 13

[k8krh]

I was reading about a safety device for trains and using a transponder which will send a signal out telling the railroad boys all is safe on the locomotive. The transponder is on CB channel 13, in which this is the CB Band, I wonder if the FCC would do anything to this situation or ignore it. If nothing done, the regular communication channels will be taken next down the road., watch out.


http://w3.usa.siemens.com/mobility/us/en/Events/railway-interchange/Documents/SIE_BRO_ACSES.pdf
DOCTOR/795

 

[ecps92]

Is there a link to this story/article ?

Are you sure it is CB??

As Amtrak is/was experimenting is PTC, but using the AMTS channels around 10 and 13 , NOT CB 13

I was reading about a safety device for trains and using a transponder which will send a signal out telling the railroad boys all is safe on the locomotive. The transponder is on CB channel 13, in which this is the CB Band, I wonder if the FCC would do anything to this situation or ignore it. If nothing done, the regular communication channels will be taken next down the road., watch out.

DOCTOR/795

 

[gewecke]

I was reading about a safety device for trains and using a transponder which will send a signal out telling the railroad boys all is safe on the locomotive. The transponder is on CB channel 13, in which this is the CB Band, I wonder if the FCC would do anything to this situation or ignore it. If nothing done, the regular communication channels will be taken next down the road., watch out.

DOCTOR/795

Are you sure its not AAR Ch.13 on Vhf your referring to? 73, n9zas

 

[k8krh]

I just posted the link, and I understand it is channel 13 on CB, the cb guys I know in Pennsylvania say it is on channel 13, wiping the channel out the ops are CB and Ham operators.
DOCTOR

 

[gewecke]

Upon reading the link, I suppose if you're close enough to the tracks you could hear the transponder data , but I would think they'd be pretty low power so no big deal. 73, n9zas

 

[ecps92]

Hmmmm - interesting
See page 5 of his link

Antenna & CTV

The antenna & CTV provide a field proven means by
which transponders can transfer information to the ACSES
on-board computer.
The antenna is mounted under the vehicle and is connected
through the CTV to the ACSES on-board computer. When
the vehicle is in motion, the antenna is turned on and
continuously transmits a sweep frequency of 27.115 MHz
downward to the tracks.

Antenna and CTV Operation

When the train passes over a transponder, the 27.115 MHz
carrier powers the transponder, which allows it to send a
4.5 MHz signal back to the train with coded information
representing the restrictions ahead.
In order to properly channel the electromagnetic field
radiation, the antenna features mechanical and
electromagnetic protection plates on all its surfaces,
except the bottom one where the electromagnetic field
is transmitt

Are you sure its not AAR Ch.13 on Vhf your referring to? 73, n9zas

 

[gewecke]

Bill, if you read above I did read the link he posted. Yes that was interesting. But I doubt that carrier would create that much interference unless you were located close to the tracks where a transponder might be. :wink: 73, n9zas

 

[robertmac]

Don't take this as expert information, but at one time a number of very low power items were in the 27 mHz range. Such as cordless mouse, cheap model remote control toy cars. Just loved pressing mic button when on Channel 14 and watching kids start moving their remote all around because their remote toy car stopped. Unkeying the mic brought more excitement.

 

[gewecke]

Don't take this as expert information, but at one time a number of very low power items were in the 27 mHz range. Such as cordless mouse, cheap model remote control toy cars. Just loved pressing mic button when on Channel 14 and watching kids start moving their remote all around because their remote toy car stopped. Unkeying the mic brought more excitement.

Yep, I remember those days as well! Cb's played hell with rc controlled aircraft too. :wink: 73, n9zas

 

[TheSpaceMann]

This is absurd!!! How could those fools put such an important device on CB frequencies??? What will happen when some insane CBer causes a train wreck???

 

[gewecke]

This is absurd!!! How could those fools put such an important device on CB frequencies??? What will happen when some insane CBer causes a train wreck???

It won't happen because data radios don't have receivers. They can't be affected by cb's.:wink: 73, n9zas

 

[gewecke]

I think railroads are going to start using remote data radios for locomotive control even more so in the future, since they effectively limit the amount of hands on, maybe even to the point of costing jobs. 73, n9zas

 

[W9NES]

27Mhz 27.113 would be 11 meters CB

 

[byndhlptom]

27MHZ data radio

"When the train passes over a transponder, the 27.115 MHz
carrier powers the transponder, which allows it to send a
4.5 MHz signal back to the train with coded information
representing the restrictions ahead."

It is using the 27MHz signal to power the transponder, it is not sending any data on 27MHz. CB transmissions would only trigger a 4.5MHZ data burst (only if close enough with needed power level).


"It won't happen because data radios don't have receivers."

Data radios do indeed have receivers (and transmitters too!). Most use modem type tone shifting (FSK) for the data. The newer ones are digital, but still have TX/RX.


$.02

 

[W9NES]

The post did say that they were using 27.113 Mhz which is CB and if you are close enough you should hear it.!!!

 

[gewecke]

27Mhz 27.113 would be 11 meters CB

Obviously, and it would be 27.115mhz. according to the article. 73, n9zas

 

[wa1nic]

Judging by the pictures, the thing only has to have a range of about a foot.

This system isn't totally different than the ID chips that are put in dogs (although they work on 100 KHz). The reader sends a signal which powers up the transponder and then the transponder sends data back. I have one of the animal readers ( I raise llamas, and they have chips in them for ID as well). My reader runs off of 4 AA batteries and they almost never need replacing, Based on battery life, I assume the power is quite low. This train sytem is probably similar, with power levels definitely sub-100 mW.

Also, the antennas for these kind of things are small and very directional loop antennas. For the train system, it is under the engine and pointed downward. That is hardly the best antenna setup if one wants to work DX, that's for sure.

I would be surprised if one could pick on of these up on a mobile CB more than a few feet away.

 

[BBB007]

Emphatically YES. The carrier is enough to disrupt all communications within a 5 mile radius on 27.115 MHz AM (Ch13) depending on elevation of the tracks. In our case this is 300+ ft above sea level on top of a ridge. I am 15 miles from the tracks and I hear it.This is not right. Folks saying it will not interfere must not have been exposed to this railway RF location system yet or do not fully understand the hardware involved.

Your frequency may be next unless something is done to prevent this pirating of our citizen band frequencies.

 

[gewecke]

"When the train passes over a transponder, the 27.115 MHz
carrier powers the transponder, which allows it to send a
4.5 MHz signal back to the train with coded information
representing the restrictions ahead."

It is using the 27MHz signal to power the transponder, it is not sending any data on 27MHz. CB transmissions would only trigger a 4.5MHZ data burst (only if close enough with needed power level).


"It won't happen because data radios don't have receivers."

Data radios do indeed have receivers (and transmitters too!). Most use modem type tone shifting (FSK) for the data. The newer ones are digital, but still have TX/RX.


$.02

Again, MOST data radios, such as scadaware for example, are only transmitters. Needed receivers are usually a separate device. 73, n9zas

 

[BBB007]

Next time I'm near a train running it, I'll record it. It is strong enough to cause "full quieting" and has a modulated audio tone that varies between 650Hz-800Hz. Thanks for your concern.