# DCC and QSI



## RIrail (May 5, 2008)

Hi all. Has anyone figured out a way to run the QSI decoder (and locomotive) from battery power but receive DCC control signals from the track? I like the QSI and battery combination reliability (I have brass track) but would also like computer track management.

thanks Steve


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## Nicholas Savatgy (Dec 17, 2008)

WHAT???????????







I WOULD SUGGEST YOU PICK ONE OR THE OTHER???????


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## lownote (Jan 3, 2008)

You can't do what you describe--DCC signals "ride" the power on the track

But you CAN have DCC and battery if you use QSI and the G-Wire receiver. Buy a QSI card, A "Gwire" receiver card, and I'd recommend the NCE throttle. You'd have many of the features of DCC on battery power


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## steam5 (Jun 22, 2008)

You can do basically what you descried. 

I think the only way to do what you’re suggesting is using a Lenz system called hybrid drive.

This is a great we site showing the system. http://www.tttrains.com/dcc/hybriddrive/

It basically uses an on bord battery back up system connect to the decoder. I use it to keep the locomotive moving over dirty track. It allows you to fully control the loco on dirty track, when on clean track the battery trickle chargers. Another way would be to put a large capacity battery and charge it before you run it. Now the loco will draw less current from the rail, meaning your booster can be lower rated (I think).

Of those two options I can’t see any advantage in the second; the first is great for dirty track. I do not have a layout yet to say how well it works, but in testing the system performed well. How else using track power can you stop on track covered by masking tape and turn lights on and off and then drive off it?

I don’t think you can do this with QSI.

If you like batteries and QSI it seems to me you should go down the track of the QSI/NCE G Wire system as Lownote mentioned.

Alan


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## lownote (Jan 3, 2008)

The Lenz system uses capacitors--high uf capacitors which recharge instantly. They can't hold that much power though, and so you won't get anywhere near the run times you get with batteries. You will get better performance across dirty track

I do basically the same thing to keep passenger car lights lit when track power is interrupted--just put a high uf capacitor in the circuit. Aristo has a capacitor board for use with their Revolution system, and QSI boards have a couple large value capacitors on them to smooth out interruptions in power.



But you can't run on battery and get commands over the track, not that I know of. I suppose if the caps work, it could be made to work, theoretically


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## RIrail (May 5, 2008)

I have read about the Lenz hybrid drive and that is what got me thinking about the possibilities. Most track problems come from oxidation, and large current draw causing micro arcing and wheel pitting, this is where the batteries come in. Most decoders take the signal and separate it from the power anyway, power to the mosfets, dcc to the micro. The Lenz hybrid seems to do this by providing a pick up point to insert the battery/cap (the Lenz allows for either). At some point the QSI has to separate the power from the signal, I was just curious if this modification could be made.

thanks Steve


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## steam5 (Jun 22, 2008)

The Lenz power module you purchase uses capacitors (I think) but I have built my own which uses AAA batteries, a nice amount of power.

Lownote what you do with your passenger cars is not what the hybrid drive system does; it’s a bit electronically ‘smarter’ than that. I’m mentioning this because I have read articles on the internet of people putting capacitors on motor outputs of decoders. With this setup when you loose contact with the rail the motor will continue to rotate with no control until the capacitor drains or connection with the track is re made.

Another example of how the Lenz system works. I have run a loco down the track with only one rail connected. This can be done by using the battery to power the decoder and the track and wheels act almost like antennas.

I haven’t heard of any modification to the QSI board that would emulate the lenz system.

Alan


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## GG (Jan 1, 2009)

Posted By Nicholas Savatgy on 05 Nov 2009 06:15 PM 
WHAT???????????







I WOULD SUGGEST YOU PICK ONE OR THE OTHER???????












My dearest of Nicks, 

Once again you are brazen and bold. Ye be so decisive...... 

gg


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