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nomad Wrote:Well, the Powercab gasped it's last breath and was consigned to the junk box.
For walk around throttles, I am looking into these.
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Loren
Loren
PWM (Pulse Width Modulation) is used by all DCC decoders to power the motors because of its efficiency (not much heat to dissipate). Unfortunately, PWM depends on the hysteresis (coasting ability between pulses) of the motor to work. If 60Hz PWM is used, some of the very high quality motors - coreless motors specifically - don't have the mass to coast sufficiently between pulses at very low speeds. These motors will overheat on 60Hz PWM. And being relatively expensive motors - generally $40 and up - the loss is even worse. Newer DCC decoders use a much faster pulse rate, typically in the neighborhood of 1KHz or higher, to avoid overheating of low mass motors and to get rid of the growling noise caused by low freq PWM. Some DCC decoder manufacturers even call this "Silent Drive".
The throttle you linked to operates at 60Hz, with no ability to modify the frequency. With most motors, this will work very well. With coreless motors and a few very good small can (think N and Z size) motors - not so good. Just a word of caution. Check your locomotive motors for overheating after operating a while at slow switching speeds. If it's too hot to touch, it's too hot.
my thoughts, your choices
Fred Wright
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Fred, thanks for the heads up. That is good to know.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 2,458
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Hi...I believe I also ordered the 3300uF capacitor from NE....
Gus (LC&P).
Posts: 437
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Thanks Gus. I received an answer about the rtr throttles with the pulse, so I am going with them. Going to order one today. Thanks everyone far all your help.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 931
Threads: 68
Joined: Dec 2008
Look forward to hearing your opinion.
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Joined: Dec 2008
Me to Shortliner, me to.
Actually, the issue of dc or dcc has been a thorn in my side for some time. I am glad it is finally resolved.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 2,458
Threads: 57
Joined: Dec 2008
The DC/DCC controversy exists mostly in the mind of modelers.....If you're running a DC layout, all you have to do to "convert" to DCC is unplug your DC pack, and put the DCC control in its place, turn it on, and you're all set. A couple of decoders in Plug & Play equipped locos (a few minutes time), and you're up & running...
What you DEFINITELY don't want to do is have DC and DCC controllers hooked up at the same time (assuming you have a DC block system installed). You could let the smoke out of a lot of components if you do.....
Gus (LC&P).
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Quote:What you DEFINITELY don't want to do is have DC and DCC controllers hooked up at the same time (assuming you have a DC block system installed). You could let the smoke out of a lot of components if you do.....
You got that right. I didn't burn any decoders that way, but I found other ways. :cry:
And the controversy was in my mind. Don't get me wrong, I have nothing against dcc. Someday when I am rich I might even go back to it. The decision was mainly a matter of economics. I could either buy a new dcc set and everything I would need to make it work on my garage layout, or buy 1 or 2 dc hand held throttles, since I have everything else for dc. Moneys talks, as the saying goes.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 437
Threads: 24
Joined: Dec 2008
I received the hand held dc throttle yesterday. This one. <!-- m --><a class="postlink" href="http://www3.sympatico.ca/kstapleton3/851.HTM">http://www3.sympatico.ca/kstapleton3/851.HTM</a><!-- m -->
What a beauty! Thanks guys for the recommendation. I have never seen my loco crawl so slow. And then today I found an MRC Cab Control 55 hand held throttle for a dollar.
The MRC is huge compared to the other one.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 931
Threads: 68
Joined: Dec 2008
Loren - Glad your pleased with your new throttle. I was very impressed, which is why I recommended it - have you tried the momentum adjustment (screwdriver in the hole at the bottom)? Not good for switching, but fun on main line running!
Jack (aka Shortliner)
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I sure did Jack. The momentum can be frustrating in the yard, but it's fun to try.
Loren
I got my first train when I was three,
put a hundred thousand miles on my knees.
Posts: 1,897
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Joined: Dec 2008
Loren, I got to this thread late, but if you haven't pitched your NCE yet, you might contact them to see if yours might be repairable. The complete systems are a bit pricey, but coming down, however the individual components used in assembly are generally quite inexpensive. If NCE is willing to look at your throttle, the cost of postage to send it in might be a worthwhile investment to see what it would cost for repair.
