From Bill Mullins comes some research that shows that The Lohman and Barkley Show was on and off the air a lot earlier than I estimated…
The L.A. Times for Feb 8 1969 says "Locally, Channel 4 Sunday at 11:30 [this would be Feb 9, 1969] premieres the Lohman and Barkley Show, a weekly 90-minute bash featuring comedy, music, interviews and guest stars hosted by Al Lohman and Roger Barkley. Singer-puppeteer Shari Lewis guests."
They got a local Emmy in 1970, and again in 1971. In late summer 1970, they moved from Sunday night to Saturday night.
The last broadcast I can find in the L.A. Times TV listings is Tues Feb 23 1971, a rerun.
Douglas McEwan mentioned being in the studio with Lohman the night Nixon snagged the G.O.P. nomination. That was August 6, 1968. If they were indeed taping on that date then the show sat on the shelf for quite a while before NBC began airing them. Perhaps they were just doing a pilot in August and didn't commence weekly production until later. In an article Bill sent me, Lohman is quoted as saying, "We started it…as a sort of pilot project. Channel 4 [the NBC station in L.A.] gave us an open-end show following the Democratic and Republican conventions, and it turned into a comedy series."
(Douglas, by the way, has a new book out that I hear is quite outrageously funny. It's called Tallyho, Tallulah! and here's a link to get your mitts on a copy. He's a very clever writer, he is.)
Douglas remembered the show being an hour. I remembered it being 90 minutes and the above quote says 90 minutes. Further research says both answers are sorta wrong. They made 40 half-hour shows but formatted them in such a way that two could be combined to play as an hour show or three could look like a 90-minute one. The format was so loose and unpredictable that that was possible. I believe it played on Channel 4 as both an hour and a 90-minute show.
As I've written before, I believe this series had something to do with the eventual appearance of Saturday Night Live in that time slot. Notice above where it says they moved it from Sunday to Saturday. That meant that the Saturday Tonight Show (reruns of Mr. Carson) was bumped to Sunday nights. Not long after, as more and more stations relocated them to the less-preferable night, Johnny informed NBC that he wanted to dump the weekend reruns. That prompted NBC to start developing something new for Saturday nights at 11:30 and I can't believe they didn't look at the semi-impressive numbers attained by The Lohman and Barkley Show and find some encouragement.
In the meantime, several folks have written me to note that there is one clip from the series on YouTube — an interview with Gisele MacKenzie. I'm not going to embed it because it's not a good example of what the series was but if you want to take a look at it, here it is.