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Mr Downtown

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About Mr Downtown

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  1. Random CTA

    My original question (which has inexplicably been moved here instead of in the accurately titled thread I started) was about whether an operator on a particular run uses the same consist all day long—or does a consist being turned back at the terminal just go out with whatever operator/run is up next on the schedule? Busjack—in the post he's now deleted—immediately snarked that I should already know the answer just from visiting Howard sometime.
  2. Random CTA

    On the SB platform at Howard? How would I know whether the operator stepping out is the one who brought the train from 95th? As for classifying this as a "fantasy post," whatever that is, maybe this forum isn't all about you.
  3. Random CTA

    Do you ever answer a simple question without finding some way to imply that the questioner is stupid? Standing on a platform at Howard, I have no way of knowing who's an operator who just came in from 95th, who's a relief operator, and who's a hostler. From mere observation, I have no way of knowing which trains are rush-period trippers that just pulled in with split-shift operators and which are baseline service runs headed back south. I don't know if operators arriving from 95th run their trains around the loop and back to the SB platform, or if some other employee has that duty while the operator gets a bathroom break.
  4. Random CTA

    Thinking of a normal ~8.5-hour run, would the operator normally shuttle back and forth his entire shift with the same set of equipment? During his meal break, would it be put on a layup track somewhere at the terminal, or would another operator take his original train out under a different number while he falls back three or four trains and takes a set of equipment that had just arrived when he returns?
  5. Metra ex CNW bilevels

    What's strange is that the paint job isn't completely done on this car, as you can see in the photo. There's still masking tape visible, coverings on the windows, and other details unfinished. Why bring this one not-ready-for-prime-time car all the way north from Kensington and park it on a Burlington yard lead?
  6. Metra ex CNW bilevels

    OK, I'll bite. If not BNSF, then who does the maintenance work on WSMTD cars?
  7. Metra ex CNW bilevels

    Wait, what property does Metra own near Roosevelt Road? If you meant the car is Metra property, I didn't realize they never use any outside contractors or send rolling stock out for work.
  8. Metra ex CNW bilevels

    Sitting under Roosevelt Road at the north end of 14th Street Yard is 7661, with the paint job mostly done. Not sure if the work was done by BNSF, or what.
  9. cab signals

    Setting aside the snark and complete guesswork offered in this thread, I talked with some experts and I think I understand better now. I was having trouble understanding how the blocks could be isolated from each other without some kind of electrical insulation. While it's technically accurate to say there aren't insulated rail joints between blocks, there are instead "impedance bonds" that prevent the audio frequency signals from traveling between blocks but do pass the 600VDC traction power. Isolating high-voltage running rails requires big hefty nonconducting blocks while low-power AC signals—not unlike what a big stereo amplifier sends to the speakers—can be blocked more easily. So at each block limit, the logic board looks at whether a train is occupying the block(s) ahead and injects the proper signal: yellow-35 mph, yellow-25 mph, or yellow-15 mph. If a train enters an occupied block, where its leader is shunting (shorting out) the injected signal, no signal will be received and the cab signal will "fail" to red.
  10. cab signals

    Huh? The same frequencies are used systemwide. And if there are no insulated rail joints, how does the train keep from shorting out the very signal it is receiving?
  11. cab signals

    Well, that also puzzles me. I'm pretty sure CTA uses fixed blocks, not the moving blocks possible under more modern systems, so it's not based on "so many feet behind the other train." In addition, Bill writes "CTA uses a high frequency cab signal system which functions without insulated rail joints separating the blocks." How exactly would that work? How would a train only pick up the signal from the block it's about to enter, and not from the next one ahead?
  12. cab signals

    I'm trying to better understand CTA's cab signal system. My understanding from Bill Vandervoort's wonderful web page about it is that the cab display shows four aspects: green, yellow, red, and flashing red, indicating the condition of the block the train is just about to enter. But traditional wayside signals, as I understand it, showed not only the condition of the block about to be entered but also the block beyond that so that trains could slow before entering an occupied block. I guess my question is whether this is a significant difference. As I understand it, CTA trains get a yellow-35mph signal when the block beyond is occupied, and this is presumably done by the occupied block sending its condition back a block so the circuitry would show a yellow rather than a green. But that same logic could have been used for wayside signals, where instead it was thought necessary to show two blocks ahead. Was this simply a judgment call by CTA in the 1960s that their braking was sufficient to not need the same advance warning that steam roads traditionally used?
  13. Lasalle Street car

    The tunnels predate even cable cars by two decades. The Washington Street tunnel opened in 1869 and LaSalle Street in 1871. These were merely pedestrian and vehicular tunnels, occasioned because the bridges were open so frequently. They had fallen out of use when the cable cars were introduced, and proved the perfect solution to the bridge problem. In 1891-92 a third street railway tunnel was built just north of Van Buren Street. After the Chicago River was convincingly reversed in 1900, the water flow scoured the riverbed and exposed the tops of the LaSalle and Washington tunnels. In a remarkable bit of engineering legerdemain, these were rebuilt at a lower level by lowering the floors and then the roofs, keeping them watertight all the while. As for the precise locations of the streetcar tunnels, the Washington tunnel lay under Washington Street, with with center entrance portals east of Clinton and west of Franklin. The LaSalle tunnel lay directly under LaSalle (a little east of the modern centerline), with portals north of Randolph and north of Kinzie. The "Van Buren" tunnel was 120 feet north of Van Buren with portals east of Clinton (under the L platform) and west of Franklin. That portal in LaSalle south of Kinzie is just a connection down to Carroll Street. The streetcar tunnel portal was in the next block, north of Kinzie. The south end of the LaSalle tunnel was cut off when the subway was built under Lake Street in 1939. The Washington Street tunnel closed in 1954. Its west portal was visible underneath the North Western Station trainshed viaduct until it was decked over in the 1980s. The Van Buren tunnel was closed to regular traffic in 1924, but was used for training and emergencies until 1952. Both portals have been sealed, but there have been occasional discussions of using it as part of a pedway link to Union Station. A bit about the tunnels from the Encyclopedia of Chicago. An interesting article about the tunnels is Piehl, Frank J. "Our Forgotten Streetcar Tunnels," Chicago History, Fall 1975. More detail about the 1910s lowering can be found in Artingstall, William. "Chicago River Tunnels—Their History and Method of Reconstruction," Journal of the Western Society of Engineers, Nov. 1911.
  14. IRM CTA bus route maps

    Andre, do you (or someone else) have the Route Descriptions chronology in any computer format? That's what seems to have been lost. I have a 1997 printout, but it would all have to be retyped or OCR'd to get it on the Web.
  15. Lake Transfer station history

    Here's the 1916 Sanborn's fire insurance map:
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