“I wish there was a knob on the TV to turn up the intelligence”

A popular joke about television’s “brightness” knob was given by the comedian Gallagher:
 
“I wish there was a knob on the TV to turn up the intelligence. There’s a knob called ‘brightness,’ but it doesn’t work.”
 
The Gallagher quote has been cited in print since at least 1996.
 
   
Wikipedia: Gallagher (comedian)
Leo Anthony Gallagher, Jr. (born July 24, 1946), known as Gallagher, is an American comedian and prop comic, known for smashing watermelons as part of his act.
     
Google Groups: bit.listserv.coco
To those requesting the “OrphanWare” discussion end.
Chet Simpson
1/28/96
(...)
“I wish there was a knob on the TV to turn up the intelligence. There’s a knob called `brightness’, but it doesn’t work.”  —Gallagher
     
Google Books
A Treasury of Humor:
Thousands of humorous stories, jokes, anecdotes and one-liners, up-to-date and categorized for ease of use

By Lowell D. Streiker
Peabody, MA: Hendrickson
2000
Pg. 400:
I wish there was a knob on the TV to turn up the intelligence. There’s a knob called brightness, but it doesn’t work. — Eugene Gallagher
 
Google News Archive
13 September 2004, The Blade (Toledo, OH), sec. D, pg. 5, col. 2:
CRYPTOGRAPH
“I wish there was a knob on the TV to turn up the intelligence. There’s a knob called ‘brightness,’ but it doesn’t work.”
 
Twitter
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‏@todayquotes
“I wish there was a knob on the TV to turn up the intelligence. There’s a knob called `brightness’, but it doesn’t work.”-Gallager, 60 today
9:53 AM - 24 Jul 2007
 
DonationCoder.com
Re: Your favorite quotes?
40hz
« Reply #10 on: December 04, 2008, 11:06:04 AM »
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“I wish there was a knob on the TV to turn up the intelligence. There’s a knob called “brightness”, but it doesn’t work. Every time I turn it all the way up, the shows stay just as dumb.”  - Leo Gallagher
   
Google Books
The Mammoth Book of Insults
By Geoff Tibballs
London: Constable & Robinson, Ltd
2011
Pg. ?:
I wish there was a knob on the TV to turn up the intelligence. There’s a knob called “brightness”, but that doesn’t work. – Gallagher
   
Storypick
19 Intelligent Jokes That You Need To Read Twice To Understand
Ananta Sharma -  28th May 2015
(...)
16. I wish there was a knob on the TV to turn up the intelligence. There’s a knob called brightness, but it doesn’t work!