------------------------------------------------------------------------- Some errors in pictures/captions in Kalmbach book "DCC made easy" by Lionel Strang. (ISBN 0-89024-616-5) 1st, 2nd and 3rd printing (see page 2 under "Printed in the United States of America": the rightmost number shows the print version) ------------------------------------------------------------------------- I think that drawings should become clear by just reading the captions. Page 6 the top: "The signal that travels from Command Station through... must meet NMRA". No: only the signal from booster to track! There is no standard about the way booster inputs the signal Page 7 bottom: The amount of cable shown bears no evidence as there is no way to compair it with the amount (and price) of new cable being installed. Page 8 bottom left: I'd like to know what kind of terminal strip is used here as I see no loops between orange or violet wires! Why no common return was used as the power packs seem to be independent. The amount of wiring would have been greatly simplified with common return. Page 8 bottom right: If this is to be the comparison to the left picture, then all individual wires should be shown, i.e the violet wires should have individual signal, and power wires displayed, and the actual connections between PSU--booster, PSU--Command Station and PSU-- Hand held Cab and individual wires showing the data connections between Cab--command station and command station -- booster, not just a kind of car wiring bus thing. You must be fair if you want to make a comparison! Page 9 bottom: I'd guess that data sent is "output", not "input". I trust that signals between Throttle and command station, as well as between booster and loco are also digital! The drawing is misleading. Also, I know of no DCC system that would have three or more levels of signal voltage between command station and booster like the red line is trying to display. Page 10 bottom: How does the blue line represent the amount of time that is involved? If the line is flat, it shows that the time is not running -- yes? The third graph has curly bracket embracing the time line and red signal. Is this correct, or should the curly bracket only cover the height of the red square wave signal? Page 12 middle (photo): Why should we put wires through individual holes? Isn't this exactly aginst the suggestion of twisting the wires to reduce interference? Page 13 top-left (photo): Why the connections are left exposed? The caption says nothing about insulating the connections? A good plan would be to slightly stagger the connections so that in case the masking tape peels off there would be less chances of short circuit. What is the meaning of having double drop wires (there are two black and two red wires from the bus wire up to track). Page 13 bottom (table): What happens between AWG 25 and AWG 24 as a vertical bar is inserted between columns here (should there have been three vertical lines!). It would have been a good plan to state that the mm is for _diameter_ of the _conductor_ not the insulation. (OK: it's clear that it is diameter (of the conductor, not the insulation) as cross section would be mm squared). It might have been a good plan to warn that if using metric system, the solid wires are often referred as conductor diameter and stranded as conductor cross section (sq-mm). Page 14 left (photo): What makes it clear that that this is suitable for AC-powered systems (Digitrax logo perhaps...). The table shows that this particular Digitrax transformer is not suitable for N or Z scale (yet the Digitrax booster has selector for booster output voltage -- hmmm....) Page 14 right (photo): If Tech II is suitable for feeding DC-fed DCC systems, please show that it is the "FIXED DC" terminals, not just any (pair) of terminals found on this picture. Both pictures add absolutely nothing to the fact that DC-fed system need DC supply and AC-fed system needs AC supply! Page 15 left (table): So, we have two columns, Scale and Amperage. What is the scale of Tortoise or Bulbs? Should we have had "All scales" here? Page 15 right: So, the number of locos means number of amps -- i.e. ten locos is ten amps and ten bulbs is ten amps or what? The booster is shorted as both wires are attached to same rail, and the loads are not fed at all as they, too, are connected to single rail. Is the section of track displayed having multiple insulated joiners or what (both rail heads are cut with a line between each tie). Page 16 top (photo): ...but I just read that the scale and voltages... (tables on page 14) Page 19 middle (photo): How does colouring of the other polarity rails show that all the rails of the turnout are powered? What is the use of having the loco stand where it is, as it is in fact having it's power cut off due to both rails being in same polarity. Should not DCC especially have all practical sections of the layout powered at all times irrespective of the way the turnout is thrown? Page 19 bottom (photo): How come a loco causes a short when travelling across a gap of a non-insulated turnout? There is no part mentioned as "gap" in the drawing on page 18 bottom, and the word "short" sounds like it is causing a short circuit (malfunction), but that is not neccesarily true, if the turnout was set correctly. Page 20 middle (photo): How does the drawing describe that only point rail is being powered, as the red line goes over the other closure rail and beyond the frog. How does colouring of one side of turnouts trackage show that also the other stock rail is powered but in other polarity? Page 20 bottom (photo): What is causing a short here? It is not obvious, more likely it shows that there will be no short circuit on the area marked with red color, as this is a turnout with insulated frog, so all rails marked red are in same polarity irrespective of the loco! Page 21 top left: Again you have got wonder-terminal strip (connects every second terminal together). I'd like to know why you feed the left turnout also from the frog end? Wild guess: the loco standing on the straight route is dead! [Corrected in 3rd printing] Page 21 top right: Why some of the violet wiring is dashed? (there must be a reason!). Why the booster and command station need the extra violet link that is not dotted? Also, where is the non-dashed violet wire between boosters connected in Booster 1? Is there always a feed through connector in a booster, or should the booster inputs only be connected together? The green loco is standing on brownish violet section of track. How does this differ from the yellow section of track except for color? [colors removed in 3rd printing] The main problem here is that there should be power wires and signal wires between DCC system components. Dashed lines try to tell they are signal wires and solid are for DCC power, but it is still wrong as boosters need power and signal. Page 22 top drawing: This is interesting: You've changed the terminal strip, but the command station isn't electrically connected to this terminal (there is a gap) -- why? We are now having the terminal strip in the middle, and the signal wiring is just split into two separate groups. I'd like to know what is the advantage of this? The terminal strip adds absolutely nothing to the system. You use same color for power supply wires and DCC power wires to rails. Is this not a bit confusing? Again we have feed through boosters, should I know which connector is the input and which is the output? Booster C is fed with an intersting PSU, it also has a pair of black wires going from it to the command station. What are those wires, what is the meaning of the wire colours and why they are not extracting from the same dots (connectors) as the power supply wires for the Booster C? Page 22 middle (photo): Dreadfully expensive and complicated looking printed circuit boards. Are those really cost effective and what is more: easy to use or connect? How about car bulb (or is the use of non-branded ideas banned)? Page 23 top: Again we see dotted violet wires. Why? Why the booster and command station need the extra violet link that is not dotted? here you've drawn omega loops so that the wires go over one track. Does this imply, that here the wires connected to bottom track are not connected to top track rails? If so, this should mean, that all other illustrations have the connection whenever wires cross tracks as surely the book must have a consistent method of illustrating things. Page 23 bottom: This is awesome: the command station is bridged between two power supplies (dangerous situation, I would say), and the boosters are only connected to power supplies, there are no signal wires anywhere between boosters and Command Station. This won't work! Page 25 top: This is intersting: the Aux. transformer (note: TRANSFORMER, not POWER SUPPLY) is connected to one of the throttle panels (perhaps?). There are number of orange wires, and some of those (three) are marked as Cab bus. What are the others? (I would only have marked one or explained the meaning of orange line elsewhere). The use of aux. supply is a special case and that has no place in this kind of book! The book is not giving the reader enough data to go on connecting telephone jacks to DCC system. I'd prefer suggesting the reader to stick with the things the maker of the DCC system has to offer, as those capable of using phone jacks are not the average readers of this book! Page 25 bottom right (photo): Again, I'd prefer suggesting the reader to stick with the things the maker of the DCC system has to offer, as those capable of making properly crimped RJ cables are not the average readers of this book! Page 26 bottom right: How does a connector on the edge of the layout make the two-way system to work as one way system? The drawing is useless, as one may still have wired throttles connected to lineside plugs and still have two way radio system. If the throttle cannot receive information, the panel (or wire between panel and throttle) should not be making any difference, or is it? (the pictures and picture captions should be self supporting or there should be a note "see text"). About caption: I've built myself a IR remote system that is capable of selecting the loco, and it is still one way system! One should be very careful when generalizing things! Page 27 bottom left: Again a feed through booster -- yes? How come this system help if the boosters aren't "auto-reversing"? What if they are both "auto-reversing"? Page 27 bottom right: This is intersting, both the Booster and the Reverser are connected to same piece of track. A guess: this won't work! You should connect the booster feeders to the turnout points end. [corrected in 3rd printing] Page 28 bottom left: Should one have labeled the programming output of the booster more clearly in the drawing? What kind of switch is DPTP? Should the wires between Command Station and Booster have different color or something? Would it be better to feed both rails of the track, and not short circuit the booster and programming track output of the Command station by connecting the wires to same rail (top rail) [corrected in 3rd printing]? Page 28 bottom right: This "DPTP" switch must be slightly different to the one shown in the left picture, as the common terminals must now be at the top. I know that this kind of switches exist, but I'd rather have used a more general kind of swith (DPDT) that has the common terminals in the middle. The drawing makes the matter more confusing. Again outputs are shoreted and other rail is dead. Of course it is possible that the command station and booster are dedicated units only for programming and that the bus is fed from "off screen" but this should be clearly mentioned in the drawing or caption. Why the wires between command station and booster are now both black? [wires connected to correct rails in 3rd printing] Page 29 top right (small photo): Uninsulated connections, danger of short circuit! The use of Tortoise motors is not a good generalisation (two wires only, etc)! Page 29 bottom: EEPROM has little use without a CPU, the brains of the decoder! Page 31 bottom (photo): What is this simplification about? If the components used in decoders are referred to, they are getting more complicated, thus making the decoders simpler to assemble, and if the component is the decoder, the decoders are getting more and more complicated in terms of more wires (functions) and extended number of CV's that need to be programmed (part of installation and testing!) Page 32 top left: Are the wires always in that order (red at the top and grey at the bottom?) What are the numbers "1" and "8"? Somehow this reminds me of the decoder plug, not the decoder -- hmmm... Page 32 bottom middle (photo): What does the arrow denote? How many DCC sockets there usually are in a loco? Knowing that it shows PIN number one, how many decoders have their plugs with pin number one marked? Page 33 top left: Why not tell us the meaning of these pins (and the orientation of the plug), or mention that it is the plug or socket, not the decoder. Page 33 top middle: What's the difference between drawing on page 32? I'm confused! Page 35 top photo's caption: I would still suggest first trying to program the decoder, as this would not blow out the decoder in case the tester is faulty, or wires accidentally mixed. Page 37 photo 4: I had difficulty in recognizing that the tape the text refers to is not the red one around the knife handle... Page 47 bottom left: Is it so that only MRC has accessories?