_o_OOOO_oo-Kanawha wrote:Weren't the Canadian roads also dedicated users of Locotrol boxcars instead of fixed slave units, saying it allowed them more flexibility in assigning DPU's?
Perhaps then a CN/CP paint scheme would also be much appreciated., plus perhaps some clearly visibile marking that this ins't just an ordinary boxcar but a Locotrol slave car.
You could be right about those early GE's. Due to their slow loading they were also prone to exhaust stack fires, something you probably don't want in a mid-train slave unit.
I wonder how the Locotrol worked in long tunnels. What was the frequency and transmission type used? Was it like PRR's inductive train phone, i.e. using the rails and code lines as propagators of the control command signals? Or was it all wireless, then bear in mind that VHF/UHF signals best carry linear and are therefor less desirable in curved, narrow valleys and tunnels. Saying mid sixties probably means analogue or crude digital computers using some form of packet transmission in an endless send/receive/acknowledge loop.
The whole of the mid sixties Apollo moon rocket used as much computing power as in one of your pocket calculators or simple mobile phone. Controlling a train is perhaps less daunting, but safety is still of paramount concern. A typical unit has 8 notches, so needs 4 bits to control it. If you want to control mid train braking you need a couple more bits. If you want a control readout of your mid-train slave units, you need a return signal as well.
You're right! Supposedly Canadian Pacific did use slave cars. I think the Canadian cars were home built and different in appearance from the Southern ones. I've actually never seen a picture of a Canadian receiver car.
As far as the how the system worked, it was wireless. The receiver cars carried 3 firecracker antennas and the masters carried two on the short hood. For tunnels or other issues where the signal dropped, the slaves would maintain their last setting for something like 90 seconds before cutting out. As a safety feature they would also cut out if there was a certain reduction in brake pipe pressure. I think its quite similar to the current system's safety features.
From what I've read, the Southern's 'radio' trains were known to be a real headache. When it worked, it was awesome, when it didnt it was a huge pain in the butt. Anyway, I thought these would be nice for SMM's NS route. I'm not sure if they were ever used between Atlanta and Chatt but I do know they were used north of Chatt in the Rathole. So I'm going to take a little modelers license and run them south!
An interesting story I've heard was that there was a slave consist cut out and sitting in the yard in Ashville, NC. A master unit proceeded to enter the yard and was supposedly previously set up for the particular slave set in the yard. Needless to say the radio car and its accompanying locomotives took off in response to the master and I guess you could say, tore up a few things.
Here's another look at the car prior to going into the game. A lot has changed since this version and I still have corrections to make to a few areas. Since it seems like I've got part of this process figured out, I'm going to start back on my GEs. One of the other loco's I have roughed out, in addition to the U18B and U36B, is a high hood B36-7 for Southern which a few were master units.
