Quote from: electrical whiz kid on March 20, 2012, 10:10:23 PM
Probably the most reliable method is to use an ammeter or wattmeter to monitor the watts o/r amperes consumed.
Rich

How does this tell you if the two locomotives are fighting one another or are running at the same speed?

Jim

Quote from: mabloodhound on March 21, 2012, 09:31:56 AM
That's not a true oval because you have two straight sections.

If you define an oval as two pairs of arcs with two different radii, then then the oval of which wilson44512 speaks is one where one of the pairs of arcs has an infinite radius.  But it may not be an oval by several other definitions.  This begets the questions "which definition is correct?" and "what exactly is a 'true' oval?"  All I can say for sure is that an oval is not an ellipse and vice versa.

Jim

I am not sure what an 8-40 p.c. board is but with older diesels, there is often little or no room for anything except the decoder.  Fortunately, there is no pressing need for anything except the decoder if you are planing on upgrading the lighting at the same time.  Using a warm white LED and its associated resistor to replace the original headlight bulb does wonders for a locomotive - more light and less heat.

Speaking of lighting, you can use the reverse lighting output of the decoder to also operate the headlight but at a lower brightness.  So when the train is stopped on a siding or at a station, all you have to do is switch to reverse to dim the headlight.  Then before you proceed, you can flip the direction switch to forward and off you go with a bright headlight.  This is a good use for the extra function output when putting decoders in cab units.  For resistors, 1000 ohms in series with the white wire and 10,000 ohms in series with the yellow wire is a good place to start.  The free ends of both resistors go to the short lead of the LED while the blue wire goes to the long lead.

Jim 

It might be possible to link two sets of crossing gates together so that each mechanism would lower and raise both outside gates (the gates NOT between the two tracks.)

Another approach would be to animate a pair of Bachmann's manual gates using one or two Tortoise motors to move them up and down and train detector on each track to operate the Tortoise motor(s).  If you use cabooses or FRED cars fitted with conductive axles at the rear of your trains, the occupancy detection sections need be only half a train length long each side of the gates.  Then the gates will drop when a train gets to within half a train length and rise again after the train has passed.  Alternately, you can make occupancy detection sections a full train length long and eliminate conductive axles on your rear end cars.  The gates will drop a little sooner but will rise about immediately after the train clears the crossing (very prototypical.)  You can even go a step further and add flashing lights and/or a gong.

Jim   

Have you checked the tender axles to make sure that each truck has the insulated wheels on the same side?  A related check is to see if the locomotive shorts when the tender wheels are lifted off the track.  The tender must be plugged in for the locomotive to run but if the wheels are clear of the rails, any wrongly installed wheel sets will not cause shorting.

Jim

A wye, like a return loop, requires an automatic reverser or other means to reverse the polarity.  If you want to show a photo or diagram (in .jpg form) of your layout, your best bet is to upload it to photobucket or similar photo site and post a link to it.

Jim

There is more to it than just matching the number of pins but that is a good start.  There is a bit of soldering to do.  This includes 2 wires to the supplied capacitor, 2 more wires if you use your own speaker instead of the one that comes with the decoder, and a few more if you decide to use the two extra decoder outputs to add some additional lighting features.

Then there is mounting the speaker.  This is an easy job if your tender already has a place to mount the speaker and holes to let the sound out.  It is a bit harder if you have to drill the holes yourself.  For best results, the speaker needs a baffle which is simply a sealed box to keep the sound waves from the back of the speaker from mixing with the sound waves from the front of the speaker.  With steam locomotives, it is usually possible to use the whole tender as a baffle although in some cases you may have to seal up a few openings.

Lastly, the decoder requires some programming.  At a minimum, you will want to change the address from 03 to something else.  To get a better match with your locomotive, you may want to change a number of the CV's which will require using a DCC system capable of programming CV's.  You might even want to change the sound scheme to exactly match a particular 4-8-4 which can be done with special sound loading programs and equipment.  But before doing all that, try the default programming and steam sound scheme that are preloaded into the decoder.

Before proceeding, you may want to read the manual for this decoder.  Don't let it intimidate you.  Rather, look at installation as a series of easy steps.  As for the programming possibilities, it usually helps to be aware of the things a decoder can do.  But it is completely unnecessary to try to remember how to make it do those things.  That is what manuals are for.   The manual can be found at this link:
http://digitrax.com/ftp/SDN144PS.pdf

Jim

Once you have an NMRA track and wheel gauge in your hand, look at it carefully.  It is designed to check whether the track gauge (distance between the inside faces of the rail heads) is between the maximum and minimum limits.  If more than the minimum distance, the two points on the bottom of the gauge will fit freely between the rails with the gauge held at a a right angle to the track center line.  If less than the maximum distance, the shoulder outside of one of the points will not fall between the rails.  The allowable variation is about a millimeter which is a lot more than you need to take off the top corner of the inside of the sharp end of the point rail.  All that is required is a stroke or two of a fine file.  Taking metal off the outside of the point rail means you have to file the full length of the taper, assuming the outer edge of the point rail is properly matched to the inner edge of the stock rail or you have to bend the point which gives the same shape as removing metal from the inside of the point.

In practice, retaining the blunt end of the point rail and setting the point rail slightly into the stock rail gives the best results of all, even though it is not prototypical.  Unfortunately, this is much easier to do when hand laying your own turnouts than when cleaning up factory made ones.  I suspect Ken's little bump of solder accomplishes the same thing, keeping the flanges away from the blunt end of the point rail.

Jim

Quote from: scotiatram on March 10, 2012, 03:21:45 PM
I have a DIGITRAX DCS 50 and the programming circuit has the resistor that came with the unit.

The 120 ohm resistor shown on page 14 of your Mobile Decoder Manual is to be connected in series with the programming track.  This is not the same as a 1000 ohm resistor connected in parallel with (i.e. "across") the programming track.  Without the 1000 ohm resistor across the programming track (NOT in series with it,) the decoder does not draw enough current to be detected by your Zephyr.  That is why you are getting a dnd (Did Not Detect) error.  And when your Zephyr does not detect a decoder, it will not try to program it.  As you have already figured out, you must switch your trolley to run off track power in order to program on your programming track.

If you cannot obtain a 1000 ohm resistor, you can alternately use blast mode programming mentioned in the DCS51 manual, available online at the Digitrax website.  This feature is also included in your DCS50 even though it was not documented in your manual.  If you use this method, be sure to observe all the appropriate precautions.

Incidentally, there is no such thing as a "nd" error.  I am assuming you are getting a dnd error  (see page 22 of your Zephyr manual.)

Jim 

No.  Not unless you use completely separate tracks with each command station.

Jim

A common problem with Digitrax Zephyr and Bachmann decoders is insufficient current for the Zephyr to detect the decoder.  Adding a 1k (1000 ohm) resistor across the rails while programming is the usual work around.

Jim

p.s. it helps to give all the details when asking.  I am only guessing that you have a Zephyr and not one of the other Digitrax systems.  If you do not have a Zephyr, by all means ask again but let us know witch Digitrax system you do have.

All three of these slow motion, stall motor switch machines can be controlled by DCC if you add an appropriate decoder.  DCC Concepts makes a decoder for their Cobalt Turnout Motor and it can also be used with Tortoise machines.  Digitrax makes stationary decoders that can handle multiple slow motion switch machines and some of these can also operate snap switches of any brand.

The only turnouts that I know of that have the decoders built in are the Bachmann ones.

Jim

"It it's not broke, don't fix it."  Slightly over gauge track rarely causes problems unless your wheel sets are under gauge or fine scale.  Under gauge track tends to lift the cars and locomotives by pinching in against their wheel flanges.  At low speed, you may never notice it.  At high speed, a pinch may throw cars and pony trucks right off the rails.

Turnouts are a different matter.  Being a bit out of gauge almost always causes problems.  If a turnout is not causing problems, I leave it alone.  But if it does cause problems, out comes the gauge.  If it is out of gauge, it is usually possible to fix it.  Increasing gauge a little bit or widening flangeways that are too tight can be done with a file.  Many modelers use a jeweler's file but I prefer a small warding file.  The gauge is rarely too wide but if it is, you can gently heat a rail with a small soldering iron (NOT a gun) and move it in slightly.  Several precautions apply: push the rail in but not down.  Check often with the gauge.  And have a wet sponge ready to quickly chill the plastic ties while holding the rail in place.

Jim

Why not try hand laying some track?  You can use the ties you want spaced as you want and you might even enjoy doing it.

I got my layout up and running quite quickly with E-Z Track and am now slowly replacing the E-Z Track with rail laid on hand cut ties. 

Jim

After following Bob's suggestions, add a small drop of conductive lubricant (eg Bachmann E-Z Lube Conductive Lubricant) to each place a bronze wiper touches the back of a wheel or an axle.  Then add one small drop of same to each and every pickup wheel.  This stuff often does wonders for recalcitrant locomotives.

Jim