Madmansam said:
By chance, Who is Mike Schweizer? or even Tim Pozar? Any story behind how those wonderful airchecks on the web for fellow radio fans to download? It is an awesome site!
Both are much revered stars of the Bay Area broadcast engineering community. Tim Pozar maintains the Society of Broadcast Engineers (Chapter 40) website at
http://www.lns.com/sbe. I first stumbled across a reference to these airchecks in an SBE newsletter:
Classic Bay Area Air Checks...
Mike Schweizer, who is known as a local phone / tech god for various Bay Area stations, has been airchecking Bay Area radio stations since the late sixties. He passed on a couple of DVDs of airchecks (only a fraction of his archive) to me (Tim) a couple of weeks ago. I have uploaded them and they can be found at:
http://audio.lns.com/ms_airchecks
Great non-telescoped stuff from...
KBRG, KDAY, KDIA, KFRC-FM, KGBS, KGO-FM, KGO, KIKX, KIQI, KLIV, KMPX, KNEW, KOA, KSFX, KTKT, KUSF, KYA-FM, KYA, XEPRS and XERB. And of course KFOG's transition from Beautiful Muzak to the current format. 
KMPX on 99.9? When I listened to the Big Band version & Rock, it was around 105 through 106 in the 60's. When did it move? Very nice clips!