E unit buzz

[srguy]

Is there any way to eliminate the buzz from a postwar 2055 steamer??

[lionelsoni]

Try driving the e-unit coil through a small bridge rectifier, like this one:  http://www.radioshack.com/product/index.jsp?productId=2062581&filterName=Type&filterValue=Rectifiers

Disconnect the coil from its present terminals.  Connect the bridge rectifier's ~ leads to those terminals.  Connect the coil to the bridge rectifier's + and - leads.

[dlagrua]

The bridge rectifier should work but it might overheat the eunit coil under DC power.  Try it and see. It should stop the buzzing

[gunrunnerjohn]

I've had good success with a plain diode and a reasonably large capacitor.  It doesn't give the E-Unit quite as much voltage (and current), but also stops the buzzing.  I also fixed one putting a small rubber stopper at the top of the plunger, it was totally silent.

[lionelsoni]

I have modified my locomotives to run on half-wave AC in a kind of poor-man's TMCC that lets me control two at a time.  The first time I tried to run one of mine on someone else's modern-"transformer" layout, it tripped the overcurrent protection immediately.  It would not tolerate the asymmetric current that my locomotive was drawing.  (I added a full-wave option to my scheme after that.)  It's possible that a half-wave rectifier on the e-unit might do the same, although the e-unit current is not as high.