Large Scale Central

A few tweaks to an RS-3, more sound, short protection

General Discussion
#1

I’ve been using my RS-3 as a test mule for a while.

A new (actually the first) sound file for my QSI titan has been released, the new “ET”, where a program runs in the decoder to actually simulate the locomotive, like a plane simulator.

Sounds fancy and goofy at the same time, but the bottom line is another step up in realism, along with higher bit rate sounds, etc.

Since I had previously learned the “secret” of the 21 screws requiring removal to take off the cab and hoods, and having destroyed the circuit board board a couple of times, I decided to “fix everything”

Hah!

Well first off when a 2 axle motor block Aristo loco seems to be awfully sensitive to dirty track, chances you the wheels and track are not the problem.

One thing that can cause problems is a derailment that causes a short between the 2 wheels of a motor block (not too often), or between the wheels of the front truck and the back truck (very typical on a switch).

When this happens you can easily damage something, and it’s often the traces on the main board that the trucks are wired to, notice the top traces on this board:

This is the second time I burned a trace, I actually burned the lower one first, did a repair and then burned the top one. You can see if these traces go, you are only picking up from one truck, thus with fewer power pickups, it will seem to be requiring cleaner track.

One solution is to put a circuit breaker on each of the track pickup leads. Why on each one? so as to protect from shorts in any combination side to side or front to rear.

In the picture below, I have added a Polyswitch to all 4 track pickup leads. For those who are not familar with these, they are a self-resetting circuit breaker, solid state (actually when too much current is drawn, they heat up and liquify inside and the liquid has a very low conductivity)

This will help avoid a very common problem. Note well: Many Aristo locos have these Polyswitches in them, but normally they are (in my opinion) in the wrong location, often protecting from a shorted motor (rare), or overcurrent on the “mu plugs”, which are only used when coupling loco power externally.

#2

The next thing I wanted to do is try out the dual speaker option on the QSI Titan.

The Aristo comes with a very good oval speaker pointing upwards through a grill in the long hood.

I thought it would be cool to try to make the horn and bell come from the cab area.

So the plan was to put a speaker into the cab.

First off all the windows are closed on the cab.

I pulled the cab apart and right off the engineer fell out of his chair. Even though there was a terrific blob of Chinese hot glue in his seat, he was not staying!

I cleaned all the glue blob off to be able to get his butt closer than 1 foot from the seat, but noticed the fundamental problem. His arms (from shoulder to elbow) were pressing on the seat arms not allowing him to sit down in place.

OK, I took an x-acto knife and cut up under his arm into his armpit. That allowed the arms to flex and it looked like I could get him into the seat, but this time he got JB weld on his butt and I clamped him in place to set. I also used a heat gun earlier to flex his arms a bit to make him more relaxed.

Once you have removed the cab floor with the seats and your recalcitrant engineer, the side window castings fall out.

I carefully cut out one window on each side, flush with the “frame” in the casting.

So far so good, now I also found the cab light that I never knew was there… and it was a bulb and it was burned out… of course.

So I wanted to replace it but the dang thing is in a housing that extends from the front cab wall to the back one, with little tabs held in place by the clear window castings. And wouldn’t you know it, one time that Aristo used gobs of glue and couldn’t get the dang things off.

By reaching into the cab and cutting off the tabs on one side, and reaching in with a big pair of linemans pliers I pulled the housing away… OK so replace the lamp, and where the heck do the wires go? Oh, there’s little channels in one of the window castings for the wires… ok.

Now it was time to work on the reason I opened the cab in the first place, put in a speaker. I got the On3 speaker fro Phoenix, about 36 mm square and cut a hole in the cab to match the cone and some of the surround.

(http://www.elmassian.com/images/stories/motivepower/aristo/rs3/qsi/2nd_speaker_installed.JPG)

You can see that the edge of the speaker is flush with the cab casting. I just free handed the hole with a dremel tool and finished it with the 1/2" drum sander.

(http://www.elmassian.com/images/stories/motivepower/aristo/rs3/qsi/2nd_speaker_hole.JPG)

All told now the horn and bell appear to come from the center of the cab, while the motor is doing the pokita pokita further down the long hood.

Very pleased with the effect.

#3

Very Nice Greg.

I enjoy this sort of read in the morning and have been to your site many a time. I’d also love to hear this and see this loco run in a video.

Thanks

Clif

#4

Coming up… I need to get a nice stereo mike setup, so you can judge for yourself on the “stereo spacing”… You can hear the sounds come from different places, although many people have stated that they THINK you cannot.

Best thing is for you to judge for yourself, it does make a difference in my opinion, just another facet of the hobby to enjoy.

Greg

#5

Looks good Greg, I like the extra speaker install . Should sound great having motor and horn noises coming from different end of the loco.

Nick

#6

Hi Greg!

Neat upgrade to the RS-3!

I am working on a USA Trains F3-A/F3-B set with blown voltage regulators and melted track power traces on the circuit boards in each unit. The insulation is also melted off the track power wires between all the sideframe bushings. As he is using a Super Revolution receiver to power and control both units, the track power would be on full and the current draw heavy whenever a short occurs because of a truck derailment. I do not know whether either he or his brother have reverse loops or wyes on their railways, so I took an extra precaution.

I built a new circuit board for each unit. Like you I added polyfuses to each of the track power wires. But because the Super Revolution is polarity sensitive, I went a step further and added a bridge rectifier after the polyfuses in each set of track power wires. So no matter what happens, the power will always came out positive on one wire and negative on the other.

I will probably switch out the light bulbs for LEDs. But I am trying to decide whether to use dropping resistors for the lights, or the CL2N3-G LED drivers. As I do not know what voltage either of the brothers is using for power, I prefer the LED drivers. But after seeing what was done to the voltage regulators, I am concerned the CL2N3-Gs will not be durable enough.

I also know from previous postings on these devices that “The sum of the voltage drops in a complete circuit must equal the voltage source. Take the voltage drop across a device, multiply it by the DC amps, you have watts. This power has to be dissipated somewhere and unless your device glows like a light bulb, it’s all in heat.” This probably sounds familiar. I have it saved under Greg’s Law in my Knowledgebase file folder. No offence intended, it just a quick way for me to find this useful information when it has to be passed on.

#7

I would put another diode in series with the CL2N3-G (note to others, the CL2 is by Suntek, and the rest of the characters denote the packaging, so you can search for CL2 also… the packaging Paul and I are using is the one that looks like a little transistor)

That diode would be in concert with your extra protection with the FW bridges in my opinion.

The cab light in the RS-3 is connected to the QSI rectified track power, so it’s getting about 24 volts to the CL2 / LED combination… I measured 20 mils just to be sure :wink:

The one issue I have not protected from though still bothers me a bit, a short between 2 wheels on the same “side” of the same truck.

I’ve opened USAT F unit trucks and found the internal pickup wire burned away or heated so much no temper was left and it was not in contact with the axle…

I’m tempted to go nuts and add extras in USAT trucks. On the old style 2 axle Aristo trucks, I have been contemplating putting 2 polyswitches inside the truck, believe it or not, between that thin wire and where it connects to the brass strips.

Regards, Greg

#8

Greg Elmassian said:

Coming up… I need to get a nice stereo mike setup, so you can judge for yourself on the “stereo spacing”… You can hear the sounds come from different places, although many people have stated that they THINK you cannot.

Best thing is for you to judge for yourself, it does make a difference in my opinion, just another facet of the hobby to enjoy.

Greg

There is as wide a range of hearing (and appreciation for good fidelity) as there are people. Years ago I ran a Pro Audio business and prided myself one being able to produce awesome sound for bands and DJ’s. Many people appreciated it but others couldn’t tell the difference between my 1000 watt PA systems and a boom box turned up to the point of complete distortion.

I’m sure I would appreciate the way your RS-3 will sound, but not sure everyone will. Most people think I’m nuts with the Minimus 3.5 speaker in my trail car for bass and a smaller speaker (or speakers in M/U units) in the locos. To me they sound great, but most don’t ever notice.

#9

ALthough I’m a steamer, I appreciate the solution for the second speaker. It gets my gears cranking for my Bachmann C-19.

#10

Thanks Greg for the advice on adding a diode with each LED driver! It was something I was considering.

Your comment on the USAT axle wipers is interesting!

I opened the trucks on this USAT F3-A/F3-B set because the bottom covers were not closed properly. Some of the axle wipers had been replaced with clunky metal rod which would not let the covers seat properly. As the rods were not sprung wire they did not maintain contact with the axles. I removed the one USAT axle wiper left in the trucks because it was bent. I replaced them all with wipers I had removed from my own diesels.

After your comment, I examined the bent wiper under my lighted magnifier. It is discolored except for the tips that contact the axles and the center that contacts the track wire bracket. It definitely does not have the spring it should have.

Oddly enough, despite the overheated wires between the sideframe bushings and the missing axle wipers, the track power and motor wires plugged into the front of the motor blocks show no signs of arcing or excess current. They are the only wires in both units that I plan to re-use.

Not having seen either of the railways that these brothers run their trains on, I have no idea how well maintained they are. Judging from the condition of this set however, I must assume the track and conductivity is less than perfect. Nor do I know what they hauling with this set. If they are USA Trains long, lighted passenger cars, the potential for high current draw and nasty short circuits with derailments is real. It is good thing I am putting heavy duty polyfuses and bridge rectifiers in these units.

#11

I’ll post up the Polyswitch part numbers soon, you will see the reduced on resistance, and I believe it will lessen problems with “false triggering”… Many of us have seen an Aristo loco shut down after running for a while, slowly heating the Polyswitch and often on a hot day.

Regards, Greg