MM 121 High Pitched Whine

[NirateGoel]

I'm just wondering if I should be concerned about a high pitched whining that my 121 has started making. It only occurs running cab first. 121 high pitch whine.mp3

It was in the middle of running in cab first when the high pitch whining began. 

It was running in on a H&M Duette but also occurs when run with a HM 2000. 

There also appears to be a short between two capacitors. C7&C8. 

 

[irishthump]

The fact that it only occurs when running the loco one way would indicate it's most likely an issue in the drive train. I would be inclined to think that this would probably  disappear with tume and more running in. 

As for the circuit board, is it causing an issue? Are the lighs working correctly?

[NirateGoel]

55 minutes ago, irishthump said:

The fact that it only occurs when running the loco one way would indicate it's most likely an issue in the drive train. I would be inclined to think that this would probably  disappear with time and more running in.

I might try that, I wanted to check lest I cause damage by doing so. I'll report back if it persists. Though I'm somewhat doubtful it's the drive train as it sounds more like coil whine, but I'm happy to be proven wrong.
 

55 minutes ago, irishthump said:

As for the circuit board, is it causing an issue? Are the lighs working correctly?

No issues that I can see not that I'd notice without comparing, just adding it on the off chance it was related. I'm not familiar enough with the circuit board layout to tell what they're for. The blacked out traces makes it difficult to tell if they should be connected or not. 

Edited January 24, 2021 by NirateGoel

[NirateGoel]

Having given it about 40 minutes extra running cab first the whine has only worsened, and is now faintly audible in the bonnet first direction. 

[irishthump]

Just now, NirateGoel said:

Having given it about 40 minutes extra running cab first the whine has only worsened, and is now faintly audible in the bonnet first direction. 

Ah not good!

If I were you I'd be contacting Murphy Models about repair/replacement. 

 

[NirateGoel]

22 minutes ago, irishthump said:

Ah not good!

If I were you I'd be contacting Murphy Models about repair/replacement. 

No, It isn't I'll give it a go round bonnet first for maybe 20 see if it improves. If it doesn't I'll give Murphy Models a contact see if they can offer any solutions. 

 

 

[Noel]

1 hour ago, irishthump said:

Ah not good!

If I were you I'd be contacting Murphy Models about repair/replacement. 

 

They have excellent warranty service direct with customers

[Joe Keegan]

Is this is the type of H&M controller that you used for 121 ?

If so , you have an problem as that type of controller is not suitable for the motors used in today’s model railways and may have damaged some of the components on the PCB.
This uses a Rheostat to increase/decrease the voltage which is ideal for today motors. H&M cease production of the Duette controller in the 80’s with the release of the Commander transistorised controller as a replacement.

 I would suggest that you look at replacing the H&M with a Gaugemaster  / Morley Controller non feedback controller.

 

 

[murrayec]

As thumper says it might be mechanical- it's hard to tell from short file you uploaded! maybe trying a small dab of oil on the axles or if your up to it have a look inside the bogie under plate to see if its oiled inside or notice anything else?

Eoin

[NirateGoel]

26 minutes ago, Joe Keegan said:

Is this is the type of H&M controller that you used for 121 ?

If so , you have an problem as that type of controller is not suitable for the motors used in today’s model railways and may have damaged some of the components on the PCB.

It was, however it was not the issue. I had even run another 121 in prior without any issue. 

I haven't had any issue with it in the past. I was unaware there was any issue with the controller. It functions grand, just using the high/low resistance switch. I don't touch the half way switch as it seems to cause the motors rather noisy and unhappy sounding. 
 

55 minutes ago, Joe Keegan said:

This uses a Rheostat to increase/decrease the voltage which is ideal for today motors. H&M cease production of the Duette controller in the 80’s with the release of the Commander transistorised controller as a replacement.

So what's the issue with the Duette if it's using the right control method? 
 

58 minutes ago, Joe Keegan said:

 I would suggest that you look at replacing the H&M with a Gaugemaster  / Morley Controller non feedback controller.

I might do, depending on their control types. From my quick research PWM seems to be the loudest of the 3 main methods. I did have a quick look and I've found 3 options regarding that. Either this Old Gaugemaster, two 'Gaugemaster D Double tracks' or a 'Morley Vortrak Zero Ten - Crawler'. I'll have to do a bit of background digging tomorrow evening to see which is the best though it'll probably be either the old one or the Morley one. 

[NirateGoel]

41 minutes ago, murrayec said:

As thumper says it might be mechanical- it's hard to tell from short file you uploaded! 

It's hard to keep the phone close enough for it to pick up the sound with the loco running. I'll try get it to work on the Rolling Road (I've only a Hornby one with 3 sets of rollers) at some point tomorrow. I can't listen to the whine anymore today. 
I'm still not 100% convinced it's mechanical, given it's coil whine like sound. But motors are not something I'm well versed in. 

44 minutes ago, murrayec said:

 maybe trying a small dab of oil on the axles or if your up to it have a look inside the bogie under plate to see if its oiled inside or notice anything else?

I'll try open it, provided it's not too resistant, I don't want to cause any more damage. 

[WRENNEIRE]

As a matter of interest which model 121 are you having trouble with
Askin' for a friend.......

[skinner75]

12 hours ago, NirateGoel said:

 

So what's the issue with the Duette if it's using the right control method? 
 

Not sure, but I think that Joe may have just missed out the 'not' or 'nt' in the line "This uses a Rheostat to increase/decrease the voltage which is ideal for today motors"

Joe Keekan to confirm!

[NirateGoel]

15 hours ago, WRENNEIRE said:

As a matter of interest which model 121 are you having trouble with
Askin' for a friend.......

MM0134 (IE edition not MMP134), however I doubt which one makes any difference.
 

5 hours ago, skinner75 said:

Not sure, but I think that Joe may have just missed out the 'not' or 'nt' in the line "This uses a Rheostat to increase/decrease the voltage which is ideal for today motors"

Joe Keekan to confirm!

Maybe, but I haven't found anything to indicate that it is bad for today's motors, only that they'll be fast off the mark and won't have the full strength of the motor. If anything it seems to be slightly better having the waste heat in the controller instead. Only issue I can find is the rheostat will wear over time. 

[NirateGoel]

Here's an new audio snippet, in the order cab forward, bonnet forward and cab forward again. 

The best option at this point appears to be to contact Murphy Models as suggested above.

Thanks all for the help and suggestions.

Copy of Monday at 15-57.mp3

Edit: both drive shafts were disconnected to record the audio. Drive chain is not the issue.

Edited January 26, 2021 by NirateGoel

[PJR]

Return to sender, as the song goes.

[murrayec]

That sounds like the motor is free running as in the gears or drive shafts are slipping!

I agree with PJR, return to sender!

Eoin

[NirateGoel]

1 hour ago, murrayec said:

That sounds like the motor is free running as in the gears or drive shafts are slipping!

I agree with PJR, return to sender!

Eoin

Well it is, I disconnected both drive shafts to try narrow it down. Hence why it sounds like that. 

Above will be edited to include that information.

[Noel]

Suggest send to MM direct in wexford street for warranty repair/replacement.

[skinner75]

Capacitors C7 & C8 definetely look like they are touching, and C5 looks a bit askew too. Pretty shonky looking placement/soldering job on those three components. 

 

[flowcoach]

Could someone add a little more clarity and detail to the question of whether Duette-style AC transformers damage the motors of modern model locomotives?

I'm very grateful for the topic coming up, as I've been a couple of days away from working with a very similar combination!

[murrayec]

2 hours ago, flowcoach said:

Could someone add a little more clarity and detail to the question of whether Duette-style AC transformers damage the motors of modern model locomotives?

I'm very grateful for the topic coming up, as I've been a couple of days away from working with a very similar combination!

I found this link on RMW after a search in Google, this guy gives a discussion on that controller, the workings of a motor related to controllers and other controllers he's played with;-

http://www.scottpages.net/ReviewOfControllers.html

There are others if you do a search 'Duette-style AC transformers and modern motors' on Google

Eoin

[NirateGoel]

On 30/1/2021 at 1:44 PM, murrayec said:

I found this link on RMW after a search in Google, this guy gives a discussion on that controller, the workings of a motor related to controllers and other controllers he's played with;-

http://www.scottpages.net/ReviewOfControllers.html

Having read through some of it, then skimmed the rest it doesn't seem to answer much. He mentioned that electronically they had bad electrical performance, but didn't explain. Nor did he mention anything about being bad for modern motors. 
 

On 30/1/2021 at 1:44 PM, murrayec said:

There are others if you do a search 'Duette-style AC transformers and modern motors' on Google

I've only found the one result with that search to a RMweb page. I only read about 2 pages of it but it seems like the Duette is safe to use on modern motors without damage, just that there's poor speed control on low resistance.