What are the currently available smooth sin wave transformers out there. I know of the MTH Z4000 and the MRC pure power dual. I would like to find one so I can run the old MPC era engines with the sin wave they were built to run on. Since they will not be doing any shunting low speed control is not an issue.Given their lower tolerance motors I rather run them with their specifications.
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I believe post war Lionel transformers were all pure sine wave.
I would jump at one if I could find one, just finding one on the west coast is a bit difficult. They only changed to chopped sin wave recently, the last 20 or so years.
MRC also has pure sine wave on some/most models. Z-1000 is also pretty good.
I run a lot of MPC on Lionel Power House via Power Master. It is chopped but they run fine. The CW-80 is the one that has the funky wave.
Also K-Line has some that are pretty good even though electrically modified. In fact my K-Line Power Chief 120 runs PS-2 fine even whey using bell and whistle buttons to trigger PS-2 features.
I use it for PW and MPC on a O-27 loop no issues. G
There are lots of PW transformers on eBay, some are reconditioned. A Z4000 should be easy to find, albeit expensive. Or, put up a listing on the Wanted to Buy, here on the forum. I am sure you will get responses from fellow members.
Um, any info out there on the GW-180?
The GW-180 is a PowerHouse 180 brick with a chopped-wave controller in front of it, it'll be just like the ZW-L, or the ZW-C with bricks, not to mention the MTH Z500, Z750, Z1000...
Anything with a physical secondary tap wiper will work. A good modern choice with some real versatility would be the Atlas/Williams 80 watt transformer - built like a postwar transformer with two variable sine wave outputs, and whistle/bell capability.
MTH Z-4000 Transformer
Just a footnote on this transformer-- it is not a pure sine wave transformer, in the sense that is mentioned in many of the post here: increased heating in motors, etc. This would include wiring from transformer to track, where the heating increases the voltage lost in the wiring getting power to the locomotives.
A particularly large layout had track power wired with #14 (although switch machine power was wired with #12 to about the same distance). Inability of large TMCC locomotives (with 2 Pulmor motors) to pull more than a very few cars at the far ends of this layout was noticed; the layout operated on a preset 18 volts to the track.
Volt and ammeter measurements suggested that the form factor of the track power was about 1.50-- that is, the waveform had a measured voltage loss in the wiring about 1.35 times more than expected. (The sinusoidal waveform has a form factor of 1.11.)
The 4000 has a fixed 27-volt secondary for its transformer. The 18-volt output was generated by passing an electronic ten-tooth comb through the positive-going 27-volt sine wave (and likewise for the negative-going half wave). This comb would in this 18-volt setting have teeth half as wide as the spaces between. Internet literature is very scant in the early '90s when this type of electronic voltage control was fairly common, but one example of a 5-tooth comb was to be found, about 3 years ago. That particular control was shown to have a form factor of about 1.35.
This showed that it would have been better to have also used #12 for the track wiring from the 4000 (a 1.26 times increase in copper area). The restriction to #14 was made, I believe and mistakenly so, out of worry that DCS signals would be affected. What I mean is, the 4000 waveform has an envelop that is sinusoidal, but the waveform itself is not sinusoidal. Instead, it had a number of harmonics overlaid, the 3rd and 5th being particularly strong. (This is similar to the 3rd harmonic of fluorescent lights, which is very troublesome to power-grid wiring.)
It is worth remembering this example when using the Z-4000. --Frank
MTH Z-4000 Transformer
Just a footnote on this transformer-- it is not a pure sine wave transformer, in the sense that is mentioned in many of the post here: increased heating in motors, etc. This would include wiring from transformer to track, where the heating increases the voltage lost in the wiring getting power to the locomotives.
A particularly large layout had track power wired with #14 (although switch machine power was wired with #12 to about the same distance). Inability of large TMCC locomotives (with 2 Pulmor motors) to pull more than a very few cars at the far ends of this layout was noticed; the layout operated on a preset 18 volts to the track.
Volt and ammeter measurements suggested that the form factor of the track power was about 1.50-- that is, the waveform had a measured voltage loss in the wiring about 1.35 times more than expected. (The sinusoidal waveform has a form factor of 1.11.)
The 4000 has a fixed 27-volt secondary for its transformer. The 18-volt output was generated by passing an electronic ten-tooth comb through the positive-going 27-volt sine wave (and likewise for the negative-going half wave). This comb would in this 18-volt setting have teeth half as wide as the spaces between. Internet literature is very scant in the early '90s when this type of electronic voltage control was fairly common, but one example of a 5-tooth comb was to be found, about 3 years ago. That particular control was shown to have a form factor of about 1.35.
This showed that it would have been better to have also used #12 for the track wiring from the 4000 (a 1.26 times increase in copper area). The restriction to #14 was made, I believe and mistakenly so, out of worry that DCS signals would be affected. What I mean is, the 4000 waveform has an envelop that is sinusoidal, but the waveform itself is not sinusoidal. Instead, it had a number of harmonics overlaid, the 3rd and 5th being particularly strong. (This is similar to the 3rd harmonic of fluorescent lights, which is very troublesome to power-grid wiring.)
It is worth remembering this example when using the Z-4000. --Frank
Well, that certainly clears it up for me. Can you really make a battery out of a potato? 
Anything with a physical secondary tap wiper will work. A good modern choice with some real versatility would be the Atlas/Williams 80 watt transformer - built like a postwar transformer with two variable sine wave outputs, and whistle/bell capability.
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