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Discussion Starter · #1 ·
I've read that some people are having problems with Airwire equipped locos slowing down on grades. I also understand that the QSI decoder with G-Wire reciever has back EMF capability, so does it also have this issue? I would assume not, but you know what they say about assumptions.
 

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Kenneth,

The QSI decoder with BEMF will not sag on grades unless the batterys do.. The AirWire receiver you have to drive like a real train, more throttle up the grade & less going down..

BulletBob
 

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Posted By Road Foreman on 09/09/2008 1:13 PM
Kenneth,
The QSI decoder with BEMF will not sag on grades unless the batterys do.. The AirWire receiver you have to drive like a real train, more throttle up the grade & less going down..
BulletBob


While Back EMF control will help with speed control, it is certainly NOT required for unattended operation. On my layout with 3% grades up and down, I don't have to "drive" any of the several power packs I've used with track power, nor do I have to drive my Aristo-Craft Trackside TE, or my battery powered Critter Controls, or a simple battery powered loco with an on/off switch, or locos with Loco-Link (no BEMF versions). Haven't tried RCS, but I'm betting it will run just fine unattended. And yes, I have tried Airwire.
 

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Discussion Starter · #4 ·
Thanks for the responses, guys. I'd heard that some people are unhappy with their Airwire-equipped locos because of the grade issue. Glad to hear it's an issue with the reciever, and not the transmitter (which I figured, but thought one ought to ask those that know).
 

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Del,

The issue is not unattended operation, the issue is slowing down on up-grades & going fast on down-grades.. All my locos slow down going up-grades & speed up coming down.. I also have Loco-Link & it does the same as regular power supply.. If you have BEMF then the decoder will keep the speed the same all the time..

BulletBob
 

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Posted By Road Foreman on 09/09/2008 5:49 PM
Del,
The issue is not unattended operation, the issue is slowing down on up-grades & going fast on down-grades.. All my locos slow down going up-grades & speed up coming down.. I also have Loco-Link & it does the same as regular power supply.. If you have BEMF then the decoder will keep the speed the same all the time..
BulletBob


I understand that Bob, and most controllers will indeed slow a bit on the up and speed up a bit on the down while running at a given speed setting. This is usually acceptable, unless the layout has ridiculous grades. However my experience with my AirWire installation on my layout was the speed changes were huge. So bad in fact, that the loco would race downhill like a roller coaster and then come to a screeching halt at the first curve or grade. So for me, the issue is unattended operation. In order to complete a loop without intervention on my part, I had to set the speed setting to "slot trains". I really don't understand why that happens either, because they are most likely using the same basic motor driver circuits the rest of the electronics world uses. I am just trying to point out that Back EMF control is not the only solution to the problem. Different controllers (without BEMF) may produce more acceptable results.
 

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Master of Disaster
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Ok....think about this....real trains power up going up grades, and brake downgrade....back emf make trains react like toys....trains....no characteristics....even speed....not realistic.

Now for turning on a train and letting it run....maybe BEMF is what you want....not sure.

Maybe if this is a issue the problem could be too much of an incline...grade...enough to make this a real problem....maybe decreasing the grade would help solve an big issue with this.

My device of choice is Air Wire...and my layout is pretty much level, and if not, there is not enough grade for a large difference of faster and slower.

G-Wire...sold it!/DesktopModules/NTForums/themes/mls/emoticons/crazy.gif

Just my 2 cents.

Bubba
 

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Discussion Starter · #8 ·
Posted By Madstang on 09/10/2008 10:04 AM
Ok....think about this....real trains power up going up grades, and brake downgrade....back emf make trains react like toys....trains....no characteristics....even speed....not realistic.

I deal with this every day at work. I'm an engineer for NS, and I do enjoy excercising the skill needed to safely handle a freight train over varied terrain. I've tried to figure out a good way to give a model railroader the same degree of control that I have in the cab, but it would involve completely redesigning the entire system. First, the locomotive needs to be able to free-wheel - there goes the worm drive in 99.9% of models. Then there needs to be some sort of brakes, on both the locomotive and the train, preferably actuated seperately. I've got some ideas on how to make that happen, but it involves a lot of extra components, time, work, etc. for not a lot of real gain.

So, on a model railroad, I want to play the part of the chief dispatcher, if you like, and assume there's an engineer on the train, keeping it running at a constant speed. Simply adjusting the throttle up and down is no more prototypical that setting it once and leaving it alone.

In any case, if one is running any great distance, I would prefer to be watching, and save the hands-on 100% attention to things like switching. Just my personal preference.

Now for turning on a train and letting it run....maybe BEMF is what you want....not sure.

See above. :) I see BEMF as having several advantages outside operation, mostly when integrated with a sound system.

Maybe if this is a issue the problem could be too much of an incline...grade...enough to make this a real problem....maybe decreasing the grade would help solve an big issue with this.
My device of choice is Air Wire...and my layout is pretty much level, and if not, there is not enough grade for a large difference of faster and slower.

I think you've hit the nail on the head, Bubba. Most layouts I've seen are caricatures of the real thing. Curves are sharper, grades are steeper, trains are shorter, etc. Thus, a control system that would work perfectly on a prototypical railroad will likely not give the same results on a more typical, exaggerated layout. I would be very interested to know the details of the situations people have complained of regarding Airwire - grade, train weight, etc.

G-Wire...sold it!/DesktopModules/NTForums/themes/mls/emoticons/crazy.gif" border=0>
Just my 2 cents.
Bubba



Your 2 cents is appreciated, Bubba, as is that of anyone with an intelligent comment on the subject. By the way, you seem to think little of G-Wire. Why? Is it because of the BEFM and steady speed, or something else? I have not seen any direct side-by-side comparison of G-Wire and Airwire yet. Can you comment?
 

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Master of Disaster
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When I purchased the G-Wire I felt that the instructions were not adaquate enough for my liking.
And when I installed it it just didn't seem to work properly...and again the instructions I recieved were no help, and I was not going to invest another $70 for the computer inteface, when I was not really convinced that I liked it.

So from the start It just left a bad taste in my mouth....and the only thing I liked about it was the standing sounds that no other sound system offered....so I went back to what I know best.

I tried to contact the makers of G-Wire, and I revieved NO HELP! from ANYONE there!/DesktopModules/NTForums/themes/mls/emoticons/crazy.gif

That didn't help either, with Phoenix, and Al at Air Wire you get all your questions answered, sometimes not what you want to hear but answers none the less...I must also add that I have RCS and both Tony and Dave are also VERY supportive with their products!:)

I recieved e-mails from considerate people trying to address my issues with the G-Wire problem with the verbage in, or lack of verbage in the instructions, but by that time it was too late!/DesktopModules/NTForums/themes/mls/emoticons/crying.gif

Now I hear for some people it is the cats meow, but out of the gate it was curtains for me...I must add maybe it is my loss, but one seems to go with whats comfortable for the one.

Maybe I should have stated my lack of interest for the G-Wire a better way..for that I am sorry..I will just suffice to say, again I have heard that it works great for some and should never be counted out for any reason....all the systems out there have their place with various applications...maybe at a latter time I might give it another try...never say never.

Again my 2 cents

Bubba
 

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I have Gwire and QSI cards in to aristo locos, and I haven't noticed any unusual behavior. It behaves almost exactly like the Aristo TE units that were in there before. It has a programmable "engine under load" feature where, s far as I can tell, changes to the throttle change the sound, but not the speed--or not much. Its interesting, I'm still figuring it out

I agree the documentation with QSI is really weak
 

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I have both Airwire and g-wire installations. The lack of BEMF in the Airwire has always been a "struggle" for me so I've installed it in locomotives that will run well with the BEMF problem. The Airwire system is very, very good, will perform many functions and is well documented. HOWEVER, with both Airwire and g-wire/QSI, it had been a tremendous "new learning curve" for me. Many times quite stressful.

I was the receipient of the system that Bubba was having so much trouble with. After much re-programming, I was able to get it running successfully. It did take much longer to program than an Airwire installation with a Phoneix P-5. With Greg Elmassian's wonderful help, I was even able to change the chuff to work off an axle magnet.

With the QSI/g-wire, I do not have BEMF problems at all. The train runs the "same" speed up hill, on the flat, and will slightly increase speed on a down grade because of the law of gravity.

I run my trains all day long without controlling them other than starting them out of the train shed, bringing up to speed and reversing direction when necessary. When the batteries go flat, I put a new set in and continue running. That's just the way I enjoy my trains.... :):cool:

Others like to do "operating sessions" with switching, moving rolling stock from one location to another. I don't run that way so my needs or "desires" for control are can be different.

That's what makes this "obsession" so much fun. It's our/your railroad and I/you can "run it" the way I'm/you're most comfortable with using what's out there for our/your needs..... We have the whole enchillada.... in alphabetical order..... Airwire, Aristo-Craft 27 and 75 mhz, Locolinc, QSI/g-wire, RCS..... Did I miss any???? Others have been around for a while and faded away because of technology changes or other reasons.

All these systems work as they have been designed by wonderfully technical people. Just depends on what we want. That's why some people drive Fords, others a Cadillac, Toyota, etc...

When we run at Marty's, most all the products will be there running and will run well. The only problem will JJ.. /DesktopModules/NTForums/themes/mls/emoticons/w00t.gif

And........... There's more stuff coming down the road the future. Technology is changing faster and faster.

Change is good????!?!?!?!?!?? /DesktopModules/NTForums/themes/mls/emoticons/w00t.gif

Just my ramblings.
 
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