求翻译：第一个使用真空管设计的放大器大约在1930年前后完成，这个放大器可以执行加与减的工作是什么意思？

The first use of vacuum tube amplifier design completed in about 1930 years ago, this amplifier can perform add and subtract work

The first to use the amplifier tube design completed in about 1930, before and after the amplifier can be reduced with the implementation of the work

The operational amplifier (i.e. “transports puts”) has the very high enlargement factor electric circuit unit.In the actual electric circuit, usually unifies the feedback network to compose some kind of function module together.Because the early time applies in the analog computer, with realizes mat

First use of vacuum tube amplifiers in 1930, before and after the completion of the design, the amplifier can perform addition and subtraction

First use of vacuum tube amplifiers in 1930, before and after the completion of the design, the amplifier can perform addition and subtraction