Questions for PS2 Experts

You are converting a PS-1 to PS-2 with a donor board so this is an upgrade and you have smoke mods to consider, proper mounting of tach, etc...  Read the PS-2 or PS-3 steam upgrade instructions on MTH Web.

There is a PCB designed to work with the PS-1 slot.  The 4-6-0 engine is not one that has it.

You can remove the diodes and feed them off the motor leads, which is what that PCB does to generate PV for smoke element and lights.  G

GGG,

Thanks for your input.  I took your advice and read through the instructions on the MTH website.  I'm planning to use the smoke unit from the 4-6-0 so I don't anticipate having to make any changes to it.  Both motors appear to be Mabuchi and the smaller one has a tach reader bracket which I believe can be modified to fit the larger motor per the instructions.  

That leaves the PCB receptacle for the tether.  Do you know what the P/N is for it?  Also, I'm not clear on your statement, "You can remove the diodes and feed them off the motor leads, which is what that PCB does to generate PV for smoke element and lights. "  Can you explain?  Are you saying remove the diodes from the PCB and splice them into each of the motor wire leads?

Thanks for your help.

Bob,

I think John posted this photo before.  Here is how you reattach the diodes.

Dave

I recognize that photo.

You probably already know this, but the gear ratios are different.  If you want the speed to be correct in scale MPH, you'll have to download a "personality file" for a Railking FEF and upload it into that PS2 board.  Thanks for sharing your progress on this upgrade!

Dave & John,

Thanks for the photo.  Do either of you know the P/N of the PCB designed to fit in the PS1 slot?  I'm assuming it has the 2 diodes attached?

Ted,

Thanks for the reminder.  I've already downloaded the file just to hear what it sounds like.

I know you can order it, but I've never had order that board.  I normally use the board with no diodes for my upgrades, but I don't have the parts file with me to obtain the part number.  Wait... I found the number for the board without the diodes: AG-0000039

John,

Just as an FYI, as of a couple of weeks ago, that part was on backorder at MTH without an ETA.

John,

When doing this upgrade do I have a choice between using the PC board with the diodes or the board with out them?  The donor loco I'm using has the board with the diodes.  I'm confused.

Thanks.

If this is your first upgrade your in for a nice ride.  Trying to transfer guts is not the way to go and if the donor engine had the boards in the engine, you won't have properly wired harness for what you are doing. 

Those diodes are a way to get away with 10 wire harness when 11 wires are needed.  The smoke element and the lights need Positive Voltage (PV) to operate.  One way to generate it if you do not have a dedicated wire to carry it, is to use the motor leads to generate it.  One of the motor leads always has PV on it.  Yel for forward and wht when in reverse.  SO those diodes ensure that a Positive voltage is available for the purple wire regardless of motor direction.  Mounting to a PCB is convenient, but some engines have them wired off the motor.  You can do that too.

Are you sure your smoke unit is a match, sometimes funnels are different so you modify the original.  If it the same then swap is easier.

You really would have been better off with a PS-32 steam upgrade kit.  G

I agree with George, I wouldn't recommend this as your first PS/2 upgrade job.

Barry, I'm glad that I have a bunch of them in my parts box now, it'll be awhile before I need them, hopefully they'll have them.  If not, I have the connectors,, and making that PCB would be very easy.

GGG,

Thanks for the detailed explanation, I have a much better understanding now.  The donor engine has the boards in the tender (see the 2nd picture) and the upgraded engine will too.  Smoke unit itself is a match.  The funnels are different but it is an easy swap.  It was only the PCB and the tach board bracket that concerned me.

I'm going to give it a shot and if I get in a bind I can always buy an upgrade kit.

It's certainly possible Bob, I've done a few of them, and I'm sure that George has done more.  There's just a number of places to come to grief.

Remember, frame ground is very bad for anything but the power input line!

Thanks John.  I plan on taking lots of pictures so I don't do anything stupid.  I replaced a couple of components on a 5v board the other day to get a smoke unit working again so I'm feeling pretty confident.

Don't get overconfident!

John,

This afternoon, I was notified by MTH that the tether recital is now back in stock.

I did have to mill out a few steamers to upgrade them. The Allegheny needed to go back on the bench a second and third time for more milling first, and then a blown smoke triac thinger ma jig..... (FET)

https://ogrforum.com/...c/ps1-to-ps3-upgrade

Sometimes you underestimate how much material is in the way! 

https://ogrforum.com/...nto-weaver-m1-2-rail

https://ogrforum.com/...l-allegheny-now-wps2

https://ogrforum.com/...steam-kit-tach-wires

or this search showed most stuff I've attempted

https://ogrforum.com/...agination.sort=SCORE

don't be afraid to try it. Just make sure nothing shorts out.

Barry Broskowitz posted:

John,

This afternoon, I was notified by MTH that the tether recital is now back in stock.

That was fast!

Thanks Joe, I'm going to give it a shot.

John,

That was fast!

Not really. I and others have been making noise about this for the better part of a year.

I had ordered a bunch of them about a year ago when I saw them available, so I guess I missed the long dry spell.

John,

Some days, you eat the bear...