like a shopkeeper or saloon keeper or a mayor or something.

I know I've seen him before, just can't place it.

Searched for Valerie Harper and Columbo. Found this, may help you: http://www.imdb.com/title/tt0068402/

but unfortunately IMDB does not have him listed, which is very unusual. They often list even uncredited performers.

She looks a little like Valerie Harper don't think it's her ??

He might be either the Engineer or Conductor on the train, in both "Green Acres" and "Petticoat Junction".

It is Rufe Davis , who played "Floyd Smoot".

There is a picture of him here-> [link:http://sharetv.com/person/rufe_davis|

Looking at the 2 pictures together, and trying to imagine the top one without the conductor hat and the bottom one WITH the hat, they look a lot like they could be same guy, to me.

Didn't save the links, but I Googled around and saw a site listing Rufe Davis as appearing on an episode of Columbo, without saying which. Or when. And another site, supposedly listing everyone who appeared, whether credited or not. Rufe Davis was not on the list, though Valerie Harper was, with one appearance in 1972, which I believe is also the year Mr. Davis passed on.

Anyway, that's all I've got. Sorry.

ETA: Mr. Davis passed away in 1974. Not 1972.
Also the site I saw listing him as appearing on Columbo is "Pinterest", which won't let me in without registering, but shows his name in the "Google tease" for the site.

but I think that actor is too old by about a generation. This is from 1972, and I think he's really from that era.

His character is "Mr. Smith from Cincinnati" or "Smitty" or perhaps "John".

I know the face. I'm thinking he did bunches of bit parts in the 60s-70s.

good news, I think I found him. Bad news, he's again uncredited!

As I recall he did bit parts but nothing substantial that I can remember. Do you know the episode? Are Carol and Alice in a sound booth or is that more of like an industrial-type observation room?

a classic episode, of course.

So yes they are in a studio. I never noticed til now the hatred on the face of the other technician.

He's the postman in this Brady Bunch episode (The Tattletale): http://www.imdb.com/video/hulu/vi1845603609?ref_=nm_rvd_vi_2

But it's a bit of a slog to go through and I lost interest about three pages in. Of course the dude would be towards to last with a "W" last name.

FYI, I found him through your Brady Bunch clue - the episode was "Dough Re Mi" http://www.imdb.com/title/tt0531085/

C. W. Moss' (Michael Pollard's) father in Bonnie & Clyde. But Taylor always had an angry face, wild hair, was already older than this guy, and would never go uncredited. And I've never seen a more hideous jacket.

"You deserve a break today...."