Capacitor use with soundtraxx DSX

Hey I saw an article on this, using a 1000 (ohm?) capacitor to help prevent power loss with dirty track. I was just wondering, how long can it power the decoder without track pickup, and what is the amp draw when charging it? I had heard that a bunch of these, upon track power up can overload your power source.

Thanks.

http://www.soundtraxx.com/documents/technotes/dcc/dsxcap_upgrade.pdf

[url]http://www.litchfieldstation.com/lobby/u_dsx.htm[url]

http://www.tonystrains.com/technews/sndtrx_buffer.htm

http://www.members.optusnet.com.au/mainnorth/alive.htm

Have fun.

Rich