Each train needs the following two components:
I'll assume you purchased a second set of these to convert your 9V train with, since you're asking how to control both trains using the same remote.
The LEGO Powered Up team has provided an FAQ for Powered Up which contains instructions for how to pair multiple Powered Up Smarthubs with one ...
Yes there is, and the standard is not unique to trains, but rather applicable to all LEGO construction. It is called MILS (Modular Integrated Landscaping System). You can find its specification in many places, but a good resource is at L-Gauge.org, where they have many more resources and standards for the LEGO train hobby.
I could imagine that this design was chosen to take care of slight angular missalignment of the tracks at the peak of the bridge (the two parts are not exactly in a straight line but slightly bent at the joint). I cannot confirm whether this is possible, because I don't own these parts, but I think for easy assembly and disassembly they have to have a little ...
Warning: LEGO pieces were harmed for this answer
How the switch works
So, how does it work then? Well, let's open it up!
The backplate is held into place by 14 pins. We'll carefully pry it open with a knife. Alternatively, we could use a drillbit to slowly scrape off the pinheads.
Both methods are destructive. The backplate needs to be glued back on ...
It is about color and length
The Duplo action brick uses a color sensor, so you want to use the correct colors
and it needs the length of the brick for the sensor to determine the color.
paper replacement (youtube)
How to 3d print your own
Color sensor for some amount of time.
I was able to make green Lego tiles work, if the area I covered was 2x8 (in LEGO scale, not DUPLO) bumps. I put a standard Lego scale 4x8 brick under the Duplo track piece, and then built up the exposed area to the height of the center of the Duplo track, and then put 2 green Lego tiles (1x8) on top. This worked ...
It is all a matter of cost versus demand. For tens of years LEGO had a separate train theme, with transformers, special metal rails, lights, switches and individual train cars and full sets. But the cost of maintaining and developing these components did not weigh up against the limited demand there was for these sets. Not many kids (90% of LEGO’s ...
I would not recommend pushing the motorized train base for extended periods of times. When you turn the motor, it will generate electricity. Unless that energy has somewhere to go, it will turn into heat. It's probably not an issue to do this a little bit for short periods of time, but I wouldn't do it a lot.
If you wish to make your train a push train, you ...
According to the LEGO Customer service website, you can control multiple train with the remote control, but not the app. Currently the Powered Up App only controls one Powered Up Hub at a time. Source: https://www.lego.com/en-MY/service/help-topics/digital/device-guides/powered-up/control-multiple
A more specific answer can be found in the LEGO City website:...
Physically, these parts are compatible. They simply rest in between the rails. Various elements have made use of the space between the rails for years, such as points:
Older trains don't have any way to understand the function elements and respond accordingly, but they won't derail or anything like that.
You can attach second train motor to B output. However it will be controlled independently from motor attached to output A. So you would need to control speed for each motor separately.
Speaking of traction. The key thing here is your train weight. You might consider putting another full battery box (unpowered) into train just to increase weight and get ...
Th easiest solution is to just use port "B" on the rear engine and then turn the "B" side remote control panel 180 degrees. They will then both go the same direction for "up" or "down". You may even find that having the rear motor 1 click lower than the front is advantageous so it isn't pushing too much in turns, trying to buckle the train.