Installing a QSI Revolution


B

bigB

Active Member
Hey everyone,

My conversion to DCC is underway and Im jumping in headfirst with an installation of a QSI Revolution U format in a P42. Question for anybody out there who may be in the know/installed one before...

Im adding ditch lights using Miniatronics 1.5v lamps. On the decoder (and in the instructions) it says to use the 5v common (red wire) from the decoder to power each side of the ditch lights. Do I need to add a resistor? It doesnt say anything about it in the instructions. I know that the other brown and green wire from the 9 pin harness will power the function side of the ditch lights.

Do I need to add a resistor to the common?

I found a guy on YouTube who does a masterful job with a Revolution installation but he uses LEDs and even then he only installs a resistor to the anode/cathode to the non-common side of the leds.



Thanks
 
It would be best to add two resistors: one for each bulb on their supply lead and then have the other leads of the lamps connected to 5volt common. The ~ value for 15ma bulbs should be at 233 ohms or the next greater value you can easily find. You can use the smallest wattage value (physical size).;)
 
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Each of my bulbs are 1.5v 30milliamps. The output from my decoder is 5 amps. Im showing I should need about 116 ohms resistance and .11 volts resistance. thinking i should use a 1/4v 150 ohm resistor to each bulb. sound good?

thanks
 
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It's 1/4 watt, 150 ohm, but yes it's good.
To figure it out you take the voltage across the resistor which is 3.5 and multiply by .030(30 miliamps) and you get .105 watts. You want to double that which is perfect for a quarter watt.
 
Ditto for 30ma.: ~150 ohm - 1/4watt.
What I was trying to emphasize above, was don't worry if you can't find the exact required size, but be sure and always go to the next value larger that is available. Your lights will be a little dimmer with a larger size and last longer, but going the other way will burn them out very fast:eek:. ;)
 
slip of the fingers there, yeah i meant 1/4 watt, not volt.
i found that little resistance formula in one of my dcc books and its definitely handy.
hey thanks for the help guys!
 
Check the QSI site carefully or if need be send an email to:
josh@amhobby.com
Josh works for QSI and is very helpful answering questions.

As I read the QSI site info, the Revolution U has a regulated power supply and 1.5 volt bulbs can be used with no resistors.

I have only used the Altals style boards and they require no resistors whether using bulbs or leds.
 
Steve58 said:
Check the QSI site carefully or if need be send an email to:
josh@amhobby.com
Josh works for QSI and is very helpful answering questions.

As I read the QSI site info, the Revolution U has a regulated power supply and 1.5 volt bulbs can be used with no resistors.

I have only used the Altals style boards and they require no resistors whether using bulbs or leds.
Click to expand...
Steve, that's interesting. I didn't use incandescent bulbs, but LED's on the 5 volt and the way I read it for them was "...the advantage that you don't need a large resistor..." That would be a great capability for the incandescent. Let me know if it includes LED's.;)
 
Rex, it looks like I am incorrect. The schematic on the website and the Revolution - U users manual read differently. The website talks of a regulated power supply. The users manual clearly states that there are no onboard resistors on the Revolution-U. So you add them as you state.

As much as I like QSI decoders, this is one area that confuses me. I have installed only Revolution - A boards (Atlas style) and they require no resistors. And then there are the differences between the QSI decoders you buy already installed and the Revolution series. The Revolution seems to have way more features, only question is if we want to take the time and effort to install vs buying ready to run.

The other nice thing about QSI is that they do update the sound files. This is, however,only useful if you own the Quantum Programmer. Since I already have half a dozen QSI decoders, I bought one. I have read that the Quantum programmer will also work with Tsunamis, but haven't tried it yet.

Sorry if I caused confusion. This is aslo why I provided Josh's email in my last post. He is a WEALTH of info and has always been willing to help when I have written.
 
Steve, the Revolution series is what they came out with for "install your own". I put two in some J1e's and have been very pleased with them. They do have much more than the orginal QSI decoders and near equal to the Tsunami, but the upgrade "chip" for the old will have the same. I installed one upgrade into a Lionel Challenger and the improvement was remarkable.

Yeah, I am still trying to figure out this download capability. There is a program file you can download that allows you to play the sound files and download the software upgrades;also, something to do with loading into the decoders via programmer. I have used this with sound playback, but haven't gone any further with it. The way I want to understand this program is it works with the the "Programmer" that acts as an interface to the track. I am curious if this is correct and can a LocoBuffer operating with this program do the same as their Programmer. Also can DecoderPro download their software file to the decoder? If you look into this, please let me know.:)
 
As far as I know......

The Quantum Programmer is the only device that will load the QSI sound files.
The Quantum Programmer allow you to update sound files and program CVs using QSI software (Q1, Q2 upgrades and Quantum CV manager).
The Quantum Programmer will also work with JMRI Pro, but reads and writes to QSI decoders only. It can write to other brands, but won't read them back.
Decoder Pro only allows adjustment of CV, it will not let you upload the sound files.

I have mine setup on a short piece of programming track. THe Programmer and software are stand alone and do not require any other DCC interface.
 
Ok thanks, Steve. That is power for the course: buy one thing with a feature, but have to buy something else to make it work...dont'cha love it!:D

The reason I said DecoderPro is it will download Digitrax sound files, but with PR2's or PR3's. BTW: take a walk through DPro's front panel (drop down menu-Loconet) and you will see that it can do a lot more than just store decoder records and adjust CV's, including config for many accessory boards. It is quite a bargain for all it can do ;):).

Thanks again.
 
Talked to Tony's TE yesterday. They said no problem for them to reprogram it, just return. Looking forward to it when it gets back.
 
Well, bad news . I got the reprogrammed decoder back today, and within an hour of having it I almost had the install done. Sound, ditch lights, backup lights. One final test of the lights...huh no lights, only the ditch lights. huh, wait now the sound doesnt work, wait now no ditch lights. what the....????

Dont know what happened but after triple checking everything to include swapping both decoders and locos, checking both the 9 pin and 8 pin harnesses, and a conversation with Josh at AMHobby (the phone was answered by someone at TTE), I determined that the decoder is faulty. We thought the light board may be bad at first, but it works fine with other non-sound decoders (this is an RTR Athearn P42 HO) and my wiring looks decent.

Anyhow, kind of bummed, waited 2 weeks for the reprogram. Thinking Soundtraxx may have been the way to go. May still go that way.

Anyone else had any similar experience getting a bad decoder?
 
Yes, unfortunately, I've had several. One QSI and one Soundtrax. I won't even count the MRC decoder, since I don't think they ever make anything that isn't defective. :) Like all things electronic, they are subject to infantile failure, where it quits just after you start using it. The good thing is that a decoder that survives the first hour or so will probably last the life of the locomotive.
 
Jim,

Thanks for telling me about your experiences. I learned early on in the DCC conversion that it seemed like a good idea to stay away from MRC decoders.

Im 99% certain this will be my last QSI revolution. I havent installed one yet, but it seems that the Soundtraxx tsunami offers easier installation, more sounds, and an equal or slightly cheaper price.
 
Guy from QSI says it may have "scrambled" and I may be able to just reset the decoder by reprogramming some CVs to their default settings. Ill see on Friday if it works...
 
bigB: don't get disillusioned just yet. Both QSI and Soundtraxx have an excellent reputation and track record. It is not all that unusual for a decoder to loose its mind and need to be defaulted and like every thing else, the occasional bad one in the batch (though I can't think of a single case with these brands). Many times, the problems encountered are something we have done. In ref. to the installations: I have both types and really can't think of any major differences.;)
 
Hey thanks for the words of encouragement. I didnt mean to slam QSI, anything but. It just seems to me that the Soundtraxx product is a bit more flexible in its use ie you can change to one of 16 horns vs being stuck with the one programmed unless you buy their programmer.

I have 4 other QSI locos that came installed and they work great. Im sure these are only minor issues with this one are most likely my own doing.

Take care,

Brad
 
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