Re: Connect 8903B to an audio amp
Victor:
Some things....
* The input impedance of the 8903B is 100K if I remember correctly.?
* The FLOAT input can be used in your amplifier does not have a common ground on the 'speaker' outputs. Else, the shell of the BNC input is connected to power line and case ground.
* It is OK to supply up to 300V AC+DC to the inputs. You can select either on the front panel.
Be careful that some amplifiers do not have outputs that are chassis common. Sometimes they are actively driven on both the + and - speaker binding posts. Also, it is all to common that the Left and Right channels do not share the -? terminals. You can check those with an ohm meter. Be careful not to hook grounded test equipment to those amplifiers that are not already referenced to the chassis, like an oscilloscope probe. The FLOAT switch on the input of the audio analyzer will add 100K impeadance to the shell of the BNC connector in these cases.
Dan in Chandler, AZ
