Usa Trains sd70mac revolution install Help please

paul delany

Registered
30 Mar 2018
125
0
53
Dublin Ireland
Hi folks anyone here ever fitted a revolution receiver into a sd70mac ,I am not sure how to wire the lighting section ..

Any help appreciated folks.
 

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
27,713
2,864
Tamworth, Staffs.
One way to do this :

Disconnect the smoke unit from the original board.

Use a DPDT relay.
Feed this with your battery supply, and arrange it as a reversing switch.
Wire the normally closed path, into the original board, so that you have forward - running lights.
Use the reverse-light feed from the Revolution to switch the relay. - This swaps the polarity of the power to the original board, so changing the directional lighting.

PhilP
 

Tony Walsham

Manufacturer of RCS Radio Control.
25 Oct 2009
2,219
50
Casino, NSW
Hello Phil.
That is exactly how I recommend all USAT locos.

Don't forget the snubbing diode across the relay coil.
 

paul delany

Registered
30 Mar 2018
125
0
53
Dublin Ireland
One way to do this :

Disconnect the smoke unit from the original board.

Use a DPDT relay.
Feed this with your battery supply, and arrange it as a reversing switch.
Wire the normally closed path, into the original board, so that you have forward - running lights.
Use the reverse-light feed from the Revolution to switch the relay. - This swaps the polarity of the power to the original board, so changing the directional lighting.

PhilP
Hi Philip can you expand a bit on your advice for me please

Paul d
 

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
27,713
2,864
Tamworth, Staffs.
Brilliant thankyou,by the way do you know anyone selling revo receivers please
Which ones?
I assume the older 'new' 2.4Ghz ones?

There are also very old one's, and (I think) a really new version.. :wondering::nerd:
 

Greg Elmassian

Registered
8 Mar 2014
4,841
698
San Diego
www.elmassian.com
I did not understand the suggestion at first, but this gives you constant, full brightness lighting that reverses direction, clearly the motors need to be disconnected from the main board and powered not from the relay but the Revolution.

The outputs of the revolution are not high current, nor protected, so please heed Tony's recommendation of the snubber diode across the relay coil.

Greg
 

paul delany

Registered
30 Mar 2018
125
0
53
Dublin Ireland
Hello Phil.
That is exactly how I recommend all USAT locos.

Don't forget the snubbing diode across the relay coil.
Hi tony I'm wanting to fit a revolution sound decoder into my k-27 ,greg mentioned you used to make an optoisolatir board the interface between a sierra sound pcb and the motor control voltage in order make the sierra pcb detect change in speed etc ?do you still have the parts to make one please.
 

Greg Elmassian

Registered
8 Mar 2014
4,841
698
San Diego
www.elmassian.com
This is the basic schematic of the Sierra isolator board, Tony Walsham may be able to comment if this solves the "full speed" issue, or the optos were needed for another issue. Notice there are some redundant circuits, don't ask me why, the manual is about 17 pages long. This was sold as a kit, or just the board, I'm not sure.

Soundtraxx19.jpg