Heathkit IO-12 Oscilloscope

The O-12 5MHz bandwidth oscilloscope came on the market in 1958. The O-12 is practically the same as the O-11 that came on the market in 1957. It has lots of similarities with all previous Heathkit oscilloscopes and can, more or less, be traced back to the very first O-1, that was the first Heath kit back in 1947. The O-12 was replaced by the IO-12 and IO-12U* in 1962, which in turn was replaced by the IO-18 and IO-18U* in 1968 and they were replaced by the IO-102 in 1971. (See also the IO-104 page).

• The Brittish Heathkit factory in Gloucester produced several kits with the letter U added to the designation. Among them was the IO-12U and the IO-18U. The U meant The United Kingdom. The IO-18U differed from the IO-18 in terms of a slightly modernized style like the rectangular CRT.

Even if it says "Laboratory Oscilloscope" on the dashboard, the O-12 has, as well as its predecessors (O-9, O-11, etc) and its successors (IO-12, IO-18, IO-102, etc) quite limited use, since both its vertical gain and horizontal sweep is uncalibrated. Only relative messurements can be made. And only AC messurements can be made due to the simple input stage.

Schematics