NYC mogul static-hiss.

I read the troubleshooting guide.
Usually it is no sound, ticking, or distorted.
My issue does not seem to fit in this category.
Happens on track power up.

Anyone know what the switch on a Ad-20 it receiver board does?
Curious if this "noise" could be caused by the power supply board?
The coil has a brass box around it separated by a cardboard insulator. The tender also has a piece of thin plastic to isolate this from the shell.
Can I power up the tender with the Railsounds board removed. Without damaging it.
That would eliminate it as the source.
Doubt it is the motherboard.

I normally swap the boards with known working boards.  You can power up the tender with the RS audio removed, it won't hurt anything.  The speaker is connected directly to the audio board, so if it makes any noise with it removed, you have a short in the wiring.

 

I would suspect the power board.

 

Bill

Removed the RS board and no hiss.
Ir board works. Coupler works.

Noticed a crack in the small RS chip socket.
Not sure if it is the cause but can not be good.

Looks like I can buy the entire board with new chips directly online for $45.00 plus the $9.00 S&h.
Are there other options?
Will the old chips work in a Rail sounds 2.5 board?
I have one with odd steamboat whistle that I do not like. 
Thx

Send me an email, I can get you a RS4 board for a lot less than that.   I've also removed the PLCC package and glued those sockets when they're cracked.

 

If you want to know how they get cracked, it's people trying to remove the chips without a PLCC puller.

 

I doubt an old RS 2.5 board is going to sound better than a properly working RS4 board.  Besides, the 2.5 board is a big ugly package that would require you to remove the RS motherboard and both of the RS4 boards!

 

 

When you remove the RS 4.0 board there is no hissing because there is no load anymore.  It could still be a Power Supply board.  Possibly more likely because of the capacitors.  You really need to swap in different Power Supply board, different RS4.0 board, and different speaker to isolate this.  G

Exactly what I said yesterday.

 

I will try that.

Just plug in another RS 4 board.

 

I realize my post was confusing.

I was considering buying a new board and using the  old chips in another tender that has rail sounds 2.5. I was wondering if they would be compatible.

 

I did not mean to imply putting the RS 2.5 board in the mogul. I doubt it would fit in the tender.

 

"It could still be a Power Supply board."

 

Yes it still could be but couplers, and IR board are working so at least part of it is ok.

 

"so if it makes any noise with it removed, you have a short in the wiring"

 

And unlikely a short in the wiring. but still possible.

 

But I will have a better idea tonight. I will update.

I don't think you said exactly what I said, I am also not sure how a wiring issue with the RS board out of the engine will cause static over the speaker.  I recommend testing with a different board in, not a board out.

I am with Bill I would test Power Supply first by swapping.  G

I suggest you go back and read more carefully next time, I said nothing about wiring from the engine.  Note that the comment about a short in the wiring was in jest when he suggested noise if the audio board was removed.

 

Now, who's the nit-picker here?

John, Please back off.  How would I know it was in jest you use smiley after every post, some time 2 or 3.  Your recommendation was pulling the Railsounds board and testing, so you need to read clearly and please stop using my post.  

 

My opinion is you need to test with boards in by swapping, and it is possible it can be a wire noise issue.  He needs to makes sure it isn't the boards first.  Power Supply is a likely source.

 

I think you may want to be a little more precise on troubleshooting post others will use.   G

 Please take your own advice!  Here's exactly what I said, and the speaker noise comment was in direct reply to one of his comments!  Note I said "boards", there are two.

 

Give it a rest.

 

FMH,  That may be the normal sound you hear when starting up the TMCC/RS engines.  Mine also do that. 

For the mogul, with the persistent static, move the power supply from one of the other engine leaving the mogul RS4 board inplace.  Does the static go away?  If so, bad PS.  If not, move the RS4.0 board in from another engine but leave the recently added power supply.  IF static goes away, move the original mogul PS back in.  If static still gone the RS4 board is bad.  If none of this make an improvement, move the volume pot around and see if that helps.  If so, swap it out.  If still no improvement, swap a speaker.  I would think one of the above could be the issues.  If none of this improves I would start looking at how the wiring is routed and possibly damaged wire that is part of the audio system.  Speaker, volume pot, serial data, battery,etc....

 

One last thing is the battery.  Are you using one?  Try one if not and see if that helps.  G

Hi GGG,

I have always used a battery in this tender. Testing without.
That way I do not have to wait through shutdown.

It seems that if the Mogul sound board worked fine in the A5 than the board should be eliminated as the prime suspect.
Also the A5 board hisses in the mogul. 
That is why I wrote "Down to either the power board, speaker, or wiring and connector/mother board.

I think putting the mogul power supply in the A5 should the next step.

My years of troubleshooting have led me to believe that the fastest way to test components is to put the suspect part in a fully functioning assembly vs putting a good component in the suspect assembly.

I agree about the power supply next.

 

My warning on place a suspect bad component in a good train is that it may damage good components in that train.  Of course the opposite is true too.  The good component may be damaged by the bad train, but at least you limit the damage and now know the bad train has other issues.  I also base it on values.  I am reluctant to test a good $120 processor on a suspect $80 power supply.  That is why I figured out static measurements to access which is bad.  Lose $200 in a single test and you will only repeat that once.  G

That occurred to me also.
Why I put the good board in the mogul first.
But I could of toasted the good A5 RS4 board. But by coincidence I just scored another tender on the bay. Part of a project to upgrade my conventional A5.

A little risk mitigation. But it lead me to believe that the mogul board was ok so I did the confirmation by putting it in the A5.

But now I see your point and it will now make most sense to put the good power supply in the mogul with.
That will either indicate a bad power supply or point toward the motherboard, wiring harness or speaker.

If the power supply proves good than it should be safe to put the PS, RS4 and IR board on the A5 board.
Mogul speaker to A5 next and at that point I will test  harness wires for shorts.

This electronics stuff is kind of fun.
I used to rebuild motorcycle engines.
This is as satisfying and a lot less messy.
Plus at my age, highballing steam engines is a lot safer than leaning into twisties.


Thanks to you and John. Different teaching styles.
But I am learning a lot and probably quicker due to the combo.

Update.

Power supply turned out to be ok.
Speaker also.

Motherboard looks ok. No signs of burned traces etc.

It is a different configuration than the k-line one, so swapping is not really an easy option.
Guess I can test the individual wires for shorts to ground.
Still curious about the brass " shield" around the inductor.
Not seen on other PSs yet. But I think the mogul is one of my newest engines with the exception of my S-2 electric.

The brass shield is actually a standard feature of later RS power supplies, it was to reduce the radiated EMI from that inductor.  It should be helping any noise issues, not causing them.  I believe the original reason was to improve the TMCC signal.

 

If the axle wipers are not on the axles, I'd fix that, I can't imagine any reason they'd be causing a problem.