Just for future reference, if you have questions like these you may want to search through the radio forum, and/or ask your question there. Chances are, the info is already there so that you don't have to wait for responses.

I just did a search on RCU for "s-pcm" in the radio forum, and got several hits. Here's one that may be of interest:

http://www.rcuniverse.com/showthread...highlight=spcm

ZPCM is an older generation of PCM from JR, and it is 512 resolution. SPCM is the newest generation of PCM from JR, and it is 1024 resolution. Both PPM and SPCM both have a stronger signal strength than ZPCM, eliminating the need for the amplifier in a Y harness.
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