Lyric discussion by BillK 

Cover art for True Dreams Of Wichita lyrics by Soul Coughing

He's talking about radio transmissions:

"Signal got lost to the satellite Got lost in the Rideup to the Plungedown" this refers to the fact that satellites have uplinks that beam information to up to them to be transmitted back down over an area.

"Man sends the ray of the electric light Sends the impulse Through the air Down to home" the ray of electric light is a radio transmission

"And you can fire out on a bus To the outside world Down to Louisiana You can take her with you" I think this refers to the fact that you can stay in contact with someone far away through radio transmission, i.e. cellular phones.

"I've seen your hand turn saintly on the radio dial I've seen the airwaves Pull your eyes towards heaven Outside Topeka in the phone lines Her good teeth smile was winding down" again, refering to radio waves and communications.

I think the whole theme is being long distance from someone and communicating with them through the air. I think perhaps theres something sort of beautiful and romantic about that, about that fact that cross country and all over the world there are people staying in touch with each other through transmissions. Sorta like reaching out and touching someone far away..

Beautiful song, I have to say..