1.2 GHz input stage - super range for frequency meters

super range for frequency meters The input stage described here was designed especially for our new fre- quency meter but it could also be modi- fied to suit other frequency counters. The layout of the input stage must be borne in mind, however, especially the fact that it has three inputs. These are: â–  A low frequency (LF) input for analogue signals from 10 Hz to 10 MHz. The sensi- tivity can be set with a potentiometer. â–  A digital input for CMOS and TTL signals up to 10 MHz. â–  A high frequency (HF) input consisting of two sections, namely a HF amplifier for frequencies up to 100 MHz and a prescaler that goes from 100 MHz up to 1.2 GHz. The "normal" HF signal is divided by 16 and the prescaler signal by 512. Each user can tailor the input stage to his own needs. If it is used with the microprocessor-controlled frequency counter we recommend that at least the sections for the three inputs be built as they are present on the front panel and they are catered for in the proces...