I've never had an IR problems with SA Explorer 8300HD boxes in the NY area - no remod device should be necessary. Actually, URC makes several OEM remotes for those boxes.
You need to turn off the IR blaster, place the emitter to the left of the time/channel display, and put the RFX-150 outside the cabinet to eliminate interference. Be sure you adjust the IR output of the emitter. Start low and move it higher until it is reliable. Check the status light on the MRF when sending commands in RF, just to ensure you are not getting interference.
If you have questions, drop me a line.
Thank you,
Damon DG
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