The Toshiba TA7222AP was used in Uniden-built and RCI-built CB and (cough) 10-meter radios for decades.
But if you look inside a pre-1980 Cobra, President, Teaberry, Robyn and other 1979 models you'll find the original, older version the TA7222P.
No letter "A", just a "P" suffix letter.
But you can't see that number when it's installed. It faces the heat sink.
Tosiba revised this part to the letter "A" suffix to fix some odd quirks. The chip above came out of a Cobra 1000GTL. It's a AM only base that looks suspiciously like a 2000 from a distance. This chip caused a low hum on the transmit audio. Oddly enough, grounding the input pin 4 made the hum go away. I have also seen intermittent static/crunchy noises from this first-version chip in 1979 radios.
Pretty sure the "A" version was used in every radio made after 1980 or so. And the "A" part doesn't have these bad habits.
Thank goodness.
But if you're seeing audio noises you can't explain in a 1979 radio built by Uniden, there's a decent chance what's needed is the updated TA7222AP. That's what fixed this Cobra 1000.
Good luck tracking one of those down.
73
But if you look inside a pre-1980 Cobra, President, Teaberry, Robyn and other 1979 models you'll find the original, older version the TA7222P.
No letter "A", just a "P" suffix letter.
But you can't see that number when it's installed. It faces the heat sink.
Tosiba revised this part to the letter "A" suffix to fix some odd quirks. The chip above came out of a Cobra 1000GTL. It's a AM only base that looks suspiciously like a 2000 from a distance. This chip caused a low hum on the transmit audio. Oddly enough, grounding the input pin 4 made the hum go away. I have also seen intermittent static/crunchy noises from this first-version chip in 1979 radios.
Pretty sure the "A" version was used in every radio made after 1980 or so. And the "A" part doesn't have these bad habits.
Thank goodness.
But if you're seeing audio noises you can't explain in a 1979 radio built by Uniden, there's a decent chance what's needed is the updated TA7222AP. That's what fixed this Cobra 1000.
Good luck tracking one of those down.
73
