Help with a secondhand battery car

Bombastic

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Hi all,

Last week I won a very reasonably priced LGB sound car on eBay that was in pretty good cosmetic condition. However, I realized once it arrived that the previous owner had put a whole radio control and battery power setup inside that I had no idea was included. So now I'm looking at a mass of RC equipment and thinking maybe it's worth buying a transmitter and new battery, ditching the power pickups on one of my old Stainz locos, and running it on battery power via the old power plug on the back. However... I know almost nothing about the electric systems that are used for this kind of thing.

Back 15 years ago I flew RC planes with 6 channel 72 MHz systems, so I understand the basics of ESCs and receivers and servos and whatnot; but I have no background with the kinds of transmitters, battery voltages and capacities, and radio systems that are used by the model train community. I don't even know what kind of transmitter layout one would use for running a train. This looks like a 2 channel 75MHz Futaba receiver running with an Rx 74 chip, which runs a massive Novak ESC and a full-size servo that flips a manual switch and appears to be a rudimentary direction control. Is this setup worth salvaging, and if so what kind of transmitter would you suggest to pair with it? And what type, size, and capacity of battery would you put in this to run a stainz or other similar LGB train with the old style connection ports in the back?

Any other pointers for setting this thing up as a battery/RC boxcar? Or should I just gut it and restore it to a normal sound car?

Tanner

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dunnyrail

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RC is RC so your experience with Aircraft should help you here. One of the outputs from the PF-R102JE Rx will be the speed controller that will likely be powered from one of the sticks. The loco can indeed be run via the plug on the rear of the loco, but if you do this you will also be sending battery power to the track unless you disable track pickup. As for power 12v will be more than adequate to power a Stainz, you may need a separate power supply for the Rx again your aircraft experience will tell you that 4aa batteries will likely be adequate.

Keep us informed how you get on, others will likely be interested in your experience.
 
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PhilP

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It looks like you have the wiring etc. for the supply to the receiver already there?
You will need to find a 75MHz transmitter that speaks 'Futaba', and decide if you wish to use a 'stick' transmitter?
You may also find the ESC is not good for fine control, at low speeds?

Before going too far, I would rig some power onto it, and see what you think of the sound. - It may be brilliant, but it may also be dire.
You should be able to provide power, and a variable voltage, into the card to get something out of it.

Good luck.
PhilP.
 
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Bombastic

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Thanks for the insights so far! Yes, it looks like there two cables for power input: One petite cable that looks about right for a small battery that inputs through an on/off switch into the receiver (at a port conveniently marked "batt"), and one very heavy duty cable that runs directly into the ESC. So it sounds like I'd two batteries to run this: a large 12-volt pack, and a smaller pack to power the receiver. My recollection is that those generally ran on 4.8 volt batteries, although I'll need to confirm that. Any recommendations on how many mAh to get for the main 12v battery?

I've disconnected the RC components from the LGB sound system; and after studying it more, it looks like the switch is linked to the sound system in addition to the main 12v battery. Surely the switch isn't just for turning sound on and off, right? There's got to be a way to control forward/backwards direction on this thing, and that switch seems like the only way to do it. But with the sound also connected there, I'm confused what the purpose of the switch is.

I would definitely be removing the track pickups. If I remove the pickups on a stainz, is there any danger of current shorting out via another place if I were to run a battery train on live powered track? I mean running a DC train and battery train simultaneously?

Futaba is a good brand (I admit with some reluctance as I used to be a JR guy), but I wonder if matching the old receiver is the best bet here? Are there any cheap receiver and transmitter combos that might be newer and a better value than using this? My recollection is that RC aircraft transmitter technology went through an absolute revolution around the time I got out of it with 2.4GHz systems starting to roll out. And there are always sources for very cheap RC components... since this thing will not be hurtling through the air, I'm a more open to using some off brand components if others have had good experience with them.

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dunnyrail

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Thanks for the insights so far! Yes, it looks like there two cables for power input: One petite cable that looks about right for a small battery that inputs through an on/off switch into the receiver (at a port conveniently marked "batt"), and one very heavy duty cable that runs directly into the ESC. So it sounds like I'd two batteries to run this: a large 12-volt pack, and a smaller pack to power the receiver. My recollection is that those generally ran on 4.8 volt batteries, although I'll need to confirm that. Any recommendations on how many mAh to get for the main 12v battery?
re mAh, you will get longer runs using higher value. BUT I would suggest testing things out with a battery pack that will take 8 1.5 batteries, this way you will be able to test things out without expending a lot of money, if you tested out your Stainz on wooden blocks you could see how this setup is without any work to Stainz.
I've disconnected the RC components from the LGB sound system; and after studying it more, it looks like the switch is linked to the sound system in addition to the main 12v battery. Surely the switch isn't just for turning sound on and off, right? There's got to be a way to control forward/backwards direction on this thing, and that switch seems like the only way to do it. But with the sound also connected there, I'm confused what the purpose of the switch is.

I would definitely be removing the track pickups. If I remove the pickups on a stainz, is there any danger of current shorting out via another place if I were to run a battery train on live powered track? I mean running a DC train and battery train simultaneously?
So long as there is no power to the motor other than from the Speed Controller then you will have isolated any issues like this. You can happily run with DC and DCC no issues.
Futaba is a good brand (I admit with some reluctance as I used to be a JR guy), but I wonder if matching the old receiver is the best bet here? Are there any cheap receiver and transmitter combos that might be newer and a better value than using this? My recollection is that RC aircraft transmitter technology went through an absolute revolution around the time I got out of it with 2.4GHz systems starting to roll out. And there are always sources for very cheap RC components... since this thing will not be hurtling through the air, I'm a more open to using some off brand components if others have had good experience with them.

View attachment 319671
Try to get or borrow a compatible Futaba system as cheep as you can, if all works well you could update to a better 2.4ghz system, second hand ones in UK at least available for around the equivalent of $30-40.
 
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a98087

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I run the same set up using modern 2.4 ghz radio gear

You need a mode 2 controller, as this has one of the sticks (normally left) set as a throttle,

The dpdt switch that is activated by a servo swaps the polarity over, as airplanes don’t fly backwards where as trains do go backwards,

I like the set up as it’s modular so easy to swap out a part of it fails, or if you want to upgrade,

I use 12v aka 3s lipo batteries

Dan
 
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