Can some one find a thread or 2 on this?
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OK; more specific: To increase engine speed, the BIG RED knob is rotated CW. Each red flash tells us that the voltage has been increased, but it does not tell us 'by how much'. The voltage increment varies with engine speed. I'm seeking some quantitative measure of 'voltage increase per flash', which I understand depends on both current engine speed AND, I believe, the engine itself.....
Is that enuff?
I doubt there is way to tell how fast the engine is going per flash. What is the point? I have been running tmcc since day one and never looked at the red flash for any reason.
Measure the voltage but your really wasting your time.
Dave
Phil, I think the only way to find this out is to remove the shell or build a test rig so you can monitor the motor voltage as you watch the flashes. That would be the blue and yellow wires at the Molex micro fit connector on the motor driver board.
No idea if they are equal increments between zero and full voltage nor if every board is the same.
Even knowing this it has little bearing on actual speed due to gearing and driver diameters and loads in the case of non cruise engines.
As for the usefulness of monitoring flashes, I do this with all my Cruise engines, Odyssey and Back EMF. I want to make sure they start to move at the first flash (speed step). A sign everything is working right.
Pete
I was trying to recall the forum discussion on this some years ago............in which the following, rather annoying, events occur: While slowly rotating the red knob, the engine speed slowly increased, as desired....up to a point. Suddenly, the next red flash was associated with a [too] large increase in speed.
I suspect that the speed steps are not truly linear all the way to top speed. I've never spent enough time tinkering to actually verify that, it doesn't seem that important to me.
The speed steps are not linear in terms of the increased voltage to the motor, with bigger jumps between the later steps. The exact difference in voltage from step-to-step probably depends upon the specific implementation (i.e., AC-motored Hudson vs DC-motored diesel), and even the stall speed. A feature I personally despise that makes your quest even more complicated... the CAB-1 has an "acceleration" feature built into the red knob. If you turn it faster, it may actually command a multi-step increase. If you turn it slowly, it may transmit commands irregularly, or not at all. In my experience, it's not very precise in the sense that x degrees of rotation corresponds to one speed step.
[Like Legacy / CAB-2, the original TMCC had the capability to go directly to a specific speed step. It was never implemented, except in a couple of computer interfaces offered for a short time by third parties. I had one of these, and had difficulty getting it to work; it's a shame Lionel didn't support this feature better during the TMCC era.]
Remember, TMCC is a one-way communications system with no feedback between the hand-held and the base (or the locomotive, for that matter.) If you send a command, there's no way to be sure it was "heard" EXCEPT for that blinking red light. The device tells you a command was received, but not WHAT command was received. The CAB-1 will not keep trying, so if you don't see a reaction, your only option is to send it again by continuing to turn the knob. When you combine the variability of the knob with the possibility that some commands may be "lost" between the CAB-1 and the base, you have a paragon of vagueness.
You can probably tell by now that I never liked the original TMCC. Remote? Yes. Control?? Not so much. With detents in the knob's rotation and an LCD display, Legacy is what the original TMCC should have been -- and still precise and robust enough for most real-world layout environments. Now if they could only address those pesky ground plane issues!
Those "ground plane issues" are inherent in the TMCC VLF method for talking to the locos. These same issues first came up when VLF was employed for remote control systems in the 60's. Talking directly to the locos (like LC) avoids this issue entirely.
Don't get me started on the issues with DCS track signals. 
As far as TMCC track signals, they're not all that severe except for pretty large layouts. Besides, we now have a cure for most of them... 
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I have never had ground plane issues and I have been using TMCC since day 1. Today I still use my tmcc cab1 remote for all my tmcc and legacy engines. For me it does everything I need it to do. No need for me to buy legacy and cab2 remote.
Yes there are things tmcc can't do that legacy can but those are not important to me so for me tmcc and cab 1 fits the bill.
Dave
Makes me wonder if you set a certain speed and put the cab 1 down will it rally hold that spot..??
It will if the locomotive has cruise, at least mine do. Obviously, if you don't have cruise, it's hard to know what speed you have.
Nonlinear response I can tolerate. But changing delta-V from increments that are small-to-reasonable per red flash to, suddenly, a BIG increase, really gets my goat!
BTW, GUNNRUNNER JOHN's DM TMCC Buffer has helped my TMCC commands MUCHO.
I have two different legacy engines that I run on one track loop. When I start them up, I count 15 flashes of the light on each one while I am turning the knob. If I do that, they will go at about the same speed. I can just sit and watch. Except for a little adjustment at one time or another, they will run for hours like that and not touch each other.
tncentrr posted:I have two different legacy engines that I run on one track loop. When I start them up, I count 15 flashes of the light on each one while I am turning the knob. If I do that, they will go at about the same speed. I can just sit and watch. Except for a little adjustment at one time or another, they will run for hours like that and not touch each other.
If you're doing that, you can get them going together using engine code 99. All engines respond to that code. After that you can then make fine tune adjustments to the individual engines using their respective codes. I often do that when running multiple engines on the same track.
davety,
Thank you, I will try that later tonight!
