Thanks Randy for the very concise explanation... and I understand what your saying... (I'm a retired computer systems specialist... and can follow most of the technical discussions)... I appreciate the time spent to put it in writing.. its making the decoder array more clear... thanks again
With a sound decoder, you have 2 'function' things on the decoder - a function 'output' wire (the function wires are actually the - side of the circuit, the blue common wire is the +) and you have sound 'slots' which contain the various sounds, like the whistle, or bell, or brake, or coupler crash. A given function key on the throttle can control a function wire, a sound slot, or both. The decoder allows remapping of which F key on the throttle controls which output wire, and in some cases you can also change what sound slot is controlled by a given function key. The defaults usually just run them in the order of their common names - which can lead to things like a rooftop beacon turning on when you hit F1 to turn the bell on. But it also allows typical modern US practice in having ditch lights flash when F2 for the horn is pressed.
The decoder instructions will tell you what each wire in the two harnesses is for. The motor end is standard NMRA practice, you have track pickups, red and black, you have motor drive wires, orange and grey, you have blue function common, you have white for front headlight, yellow for rear headlight, and the green and violet for F1 and F2 (default mappings - but you cna assign any function key to the green and violet wires, it does not have to be F1 and F2).
The speaker end is proprietary, the manual should mention the wires and what they do. Besides the speaker and capacitor, you will have a chuff cam connection for using a cam to synchronize steam loco chuffs. There may also be extra wires defaulted to F3 and F4, maybe more. On a non-sound decoder, those connections are often on solder pads on the decoder, but on the sound decoder, since they have 10 pins available and don;t need all of them for basic functionality, you get wires instead of solder pads.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Well I'm getting very close to understanding this... (and I do realize that I made a typo earlier... it is the yellow and white wires for the lights... orange and gray for motor...) So the Function buttons on the command station don't actually relate one for one to the function terms on the decoder... my concern was that I was missing something with those "function wires F1 - F4)... I'm not having any additional functions... so they will be left unused... thanks
With this info.. I'm confident that I can now understand some of the jargon with the digitrax info and documentation... thanks much... joeg
joegib so these are for lighting? I have the manual sheet.. but I'm hooking the yellow and orange wires to forward and rear lights... and I'm assuming these will work off throttle forward and reverse. I'm confused about the F1 F2 F3 and F4 buttons on my command DCS51,, aren't these the Function buttons... if I push F1,,give Bell, F2 gives horn,,,etc... So how is the F1 green wire activated if F1 on my command sta says its for a Bell... so the four functions on the decoder are for special lights...if used, they then go to that special light/functions.. and the return wire for these are the the Blue wire? like the forward light and reverse lights...
so these are for lighting? I have the manual sheet.. but I'm hooking the yellow and orange wires to forward and rear lights... and I'm assuming these will work off throttle forward and reverse.
I'm confused about the F1 F2 F3 and F4 buttons on my command DCS51,, aren't these the Function buttons... if I push F1,,give Bell, F2 gives horn,,,etc...
So how is the F1 green wire activated if F1 on my command sta says its for a Bell...
so the four functions on the decoder are for special lights...if used, they then go to that special light/functions.. and the return wire for these are the the Blue wire? like the forward light and reverse lights...
Download the manual. I just looked at the manual. Pretty clear.
Usually a data sheet comes with decoders. All mine have.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
Well, I'm progressing with my first installation of a SDH166D into an Bachmann 4-8-4 Niagra... I've been studying and learning fairly well...but am confused about the F3 (brown) and F4 Yellow wires on the 10 pin sound harness... (not hooked up anything until I understand completely what I'm doing)
I know where all the wires go on the motor and function harness... and find that pins 3,6,8,9,10 are already hooked to the speaker and capacitor.
Pins 2 and 7 are not used...
Question: that leaves pin1 (brown) and Pin4 (yellow)... what and how are these used?
Next question is that I'm not using Pin1 (violet - F2) and Pin9 (green F1) on the motor/rack function harness... is this correct?
How is it that the various Function buttons on my DCS51 automatically control the sounds when pressed,,, F1, F2, etc... without hooking up the F1, F2 F3 and F4 wires on the decoder? is the software controlling this...
this is where my confusion lies... I've spent hours trying to search thru many articles but never seem to get clear answers.. its always the details.. and rarely the bigger picture.... any help would be appreciated... thanks Joeg