Thanks, that makes more sense now.
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Leave it to Woke: not only explain but have anecodotal case of simplifying the fancy stuff. Love it. Regards Bob (I remember your telling that story along with several others) endmrw0529251226
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James thanks to you from 1988 and myself. As 1988 showed the āplanā of āreverseā used to actuate turnouts, he mentioned a capacitor. That got me started on this tangent. Everyone knows how I FIY stuff. Follows is a plan in my mind.
- I ran across a huge value capacitor (Iām told, audio equipment usage). This with two more items could really make for A CHEAP authentic sound system.
- Get two identical transformers, both being activated simultaneously of speed control. I had hoped to build a control stand and the notched throttle lever would move both of the throttles the same amount at the same time.
- This first throttle output (transformer) would be connected to a sound module which I have and depends on voltage to simulate the SOUND of a loco. Thus notch 8 is a wide open diesel engine sound.
- On the other hand the second transformer (also notch 8) would power the huge capacitor connected to the track. As the voltage slowly (loco slow movement) rises due to the capacitor charging, the engine is screaming. Sound familiar?
- Next neat result. Capacitor is now fully charged. Loco moving briskly and continues to. Wipe the throttle to notch 1. Sound settles down BUT the voltage of the capacitor slowly discharging will have the loco coasting for some time. COOL.
- What if I goof. I gotta stop. Loco brake stand (again control stand simulate with handle/levers that activate items inside) first position places a resistor to increase discharge rate, second notch = smaller resistor to more rapidly decrease voltage/speed, and finally Emergency is last notch = short circuit to the capacitor. Dead/stop
- Sorry you guys with DCC, this aināt that fancy but I love dreaming up unconvential ways to do things. regards mike endmrw0529251257
ADCX reference post #10.
Would post A be for one train and the speed control would be the contact plate assy? Post B would be for a second train?
The terminal C would be for a āmateā to the track activated by A? i.e A-C one train
Then the mate for B would be terminal F? B-F = second train
Terminals D and E are for accessories?
Please, one more question. Post #14. Since the larger transformer has four knobs. As you said two are for accessories and the other for two trains?
Thanks regards mike endmrw0529251316
So youāre essentially saying that you want to build a āelectronic flywheelā, AKA a momentum simulator coupled with a sound system?
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MP104 - That is actually a type of āmomentumā system used in the straight DC days of HO and N scale. Although a large capacitor will work, the momentum throttles would use a power transistor to vary the voltage to the track, and the capacitor would be on the base lead of the power transistor with a resistor to control the rate of charge. A brake switch would use a resistor to discharge the capacitor quicker. Your idea of using a separate throttle to run the sound system is interesting.
However, this type of momentum circuit is really intended for DC trains. Using a capacitor alone will not work on an AC train since the AC is effectively charging and discharging the capacitor at 60 Hertz. It would take a more complicated circuit to simulate momentum by slowly raising or lowering the voltage on AC powered trains.
It can be done with enough engineeringā¦
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1988 EXCELLENT vocabulary. Bravo. endmrw0529251340
James, ref #65
My AC days are over. When getting into HO, all that stuff unfortunately I did not save.
This is why Iāve had so many questions of you guys. Reflecting on my starter days. I see why your concerned about how my idea since this thread deals w/AC. Mine works ONLY on HO/DC.
Interesting that you mention in the past my idea was used commercially (donāt tell the patent holder, please). Too, the clever electrical trick of whistle ātriggerā(especially pull and then hold steps) in tender was neat to read of. Regards mike endmrw0529251354
Why, thank you!
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Unconventional? Isnāt that the way momentum throttles have worked since, oh, the seventies? Service braking, too, and the āemergency stopā position that cuts track voltage immediately?
Problem with a big cap is a big BANG if you short it. People are used to toy trains being ālow voltageā but a good capacitive discharge to a piece of metal youāre holding, like a screwdriver, can give you an annoying burn. Better to use the discharging capacitor to control switching through a power transistorā¦
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There ya go Bob. Youāre recommending what SHOULD be done. I have had fun with the DISCHARGE of that big ole capacitor. It sure sounds off and anyone unsuspecting is āshockedā (Iām sorry I couldnāt resistā¦that is they are alarmed).
This CERTAINLY is the time to teach people about capacitors. No battery, no power cord, not been turned on in a long timeā¦Watch Out. If there is a high voltage capacitor in there, you could be in for a surprise.
As for your warning, yes my emergency brake will have contact problems, might even weld contacts together. Lets depend on my excellent operating style and only the two earlier stages of braking will not cause me to āfryā a switch. LOL endmrw0529251801
I always try to short out capacitors when Iām opening anything up, particularly the big onesā¦ better to discharge it harmlessly through a screwdriver than harmfully through my body.
-El