PFM/PBL Sound in K-27

[glennk28]

Has anyone set up a K-27 with PFM or PBL sound?  Basically it uses a small capacitor connected across the rails intermittently with the trigger to cue the chuff, and a speaker with  blocking capacitors and an RF trap connected acrpss the rails. 

I guess the big question is the chuff trigger cap.  gj

[Kevin Strong]

The only thing I can warn you with respect to the PFM system stems from dad's and my use of it in the early 1980s. What we discovered was that the track itself built enough capacitance over its length to where the base unit couldn't tell that the chuff had been triggered. At the time, the railway consisted of around 300' of code 332 aluminum rail. I can't tell you if rail material, distance, or what factors caused this phenomenon, but at the outer points of the railroad, the chuff would become erratic. Dad tried a few different things to remedy the problem, but ultimately gave up. A switch to on-board batteries solved that problem, as the sound systems then moved onboard as well.

Whether today's systems use different electronics or capacitance values, I don't know. I would be inclined to believe something would be different given the change from analog to digital sound recordings, but that's idle speculation on my part.

Later,

K

[glennk28]

Thanks--I have several of the PFM, PBL, and Soundtraxx systems for the On3 and O Scale--thought I might try setting up the K-27 with it--I recall having some trouble with the outdoor railroad when I was in Marina, bu thought it was due to the sea air.