Since your running ver1.3, this should work. It does not work on any newer versions.

From the origional tivo hack faq:
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The quotes surrounding the variable should be ommitted when placing it in the boot parameters or in the /etc/rc.d/rc.sysinit file. NOTE. When placing this variable in the rc.sysinit file you should put the word "export" in front of it. For example "LIVE_CACHE_SIZE=20700" would look like "export LIVE_CACHE_SIZE=20700". You do NOT need to do this if you are placing it in the boot sector, and can use them exactly as shown below.

"LIVE_CACHE_SIZE=20700"

Adding this changes your live TV buffer from 30 minutes to 60 minutes. If you set it to 10350 that will give you the normal 30 minute buffer. So increase it by 10350 for each additional 30-minute interval you want to add to the live buffer. A few things should be noted about this hack:

Don't try creating a buffer larger than your free space. So if you have a 30 hour unit and you have 29 hours of shows recorded, do not try to increase your live TV buffer to 4 hours (82800).

The TiVo ``green bar'' indicator still thinks the live TV buffer is 30 minutes, but it will still work with your new settings.
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