Williams 150 Watt Transformer - Is it pure sine wave?

I'm sure that it's not, that will have the typical chopped waveform.

Thank you very much. I am looking for a modern transformer to run the older QSI Weaver & MTH locos. What about the MRC 130 watt pure power transformer?

I do not believe so on the Williams.

The MRC AH501 O Scale 130 Watt Pure Power whole spiel is around pure sine wave power, so I would hope that it is!

This one is a pure sine wave transformer.

Thanks for the replies, I will look for the MRC unit.

gunrunnerjohn posted:

I'm sure that it's not, that will have the typical chopped waveform.

Hi John,

I can confirm it is not.  Its a phase fired triac run by a microchip PIC.  The firing times are controlled by the PIC to stagger the firing times to simulate a DC offset for whistle and bell.  

We both know the designer 

Lou N

The MRC is, as John says, definitely pure-sine-wave and will run anything.  I’ve run everything from conventional Lionel and Williams, to MTH PS1 and PS2 with no problems.  Only complaint I have is that it slows the train when you activate the bell or horn.  Simple design, plenty of power for one train.

Lou N posted:

gunrunnerjohn posted:

I'm sure that it's not, that will have the typical chopped waveform.

Hi John,

I can confirm it is not.  Its a phase fired triac run by a microchip PIC.  The firing times are controlled by the PIC to stagger the firing times to simulate a DC offset for whistle and bell.  

We both know the designer 

Lou N

Sounds like you know a lot about this one.   I was sure just looking at the separate brick that it was not going to be a pure sine wave.

That MRC has been discontinued for two years

bluelinec4 posted:

That MRC has been discontinued for two years

You can still find them on the secondary market, I got mine NIB on the auction site.  Is the Dual Pure Power still in production?

No it’s not. They only have a 50 watt transformer available.  They just moved.   I have a feeling they are having troubles

Atlas has a nice 80 watt transformer, they also produced it for Williams, that is readily available if that power would be sufficient for your needs.  I’ve seen them sell for around $50.

Thanks for all the input, I just bought a MRC 150 watt from Trainz.

bluelinec4 posted:

No it’s not. They only have a 50 watt transformer available.  They just moved.   I have a feeling they are having troubles

If they are having problems that sucks... I’ve been using their power packs for HO since at least the mid 90’s, always been happy with their products.  I’d hate to see them go.