[AMSAT-BB] QRP ISS?

This is probably old news to you ARISS guys`, but I thought I would report on a little experiment I tried yesterday: putting my TH-D72 on 145.825 during an ISS pass.   Yesterday morning included a pass with max elevation of 56 degrees, so I screwed in the rubber duck, set the radio for APRS, and waited.  As expected, I had no trouble hearing ISS.  Six stations relayed by the ISS digi showed up on my list.  However, also as expected but a little disappointing, ISS didn't hear me.  Several high  power fixed stations drowned out any QRP stations who might have been there.  They appeared to be operating automatically,  I won't mention any calls here, but if you're one of them, you know who you are.  My grid square is DM41.. 73 Ray W2RS