HP 8517B Theory of Operation, The RF Source Power •, Figure 5-1Standard HP 8517B RF Block Diagram

Troubleshooting the Test Set

Theory of Operation

RF paths for Port 1 and Port 2 are similar. This section discusses in detail the source power signal, as it is routed via the RF IN connector, through the test set, and to Port 1 for S11 and S21 measurements.

The RF Source Power •

•

Figure 5-1 Standard HP 8517B RF Block Diagram

RF source power enters the test set through the rear panel. The RF power is applied to the switch/splitter (A18).

At the switch/splitter, the power is attenuated by approximately 7 to 14 dB, depending upon frequency.

The switch/splitter receives its control signals from the attenuator/switch driver board (A5).

The switch part of the switch/splitter, which is a combination of two power splitters and a solid-state switch, selects the power splitter to use and, therefore, the test port to receive the RF power.

LEDs on the front panel and on the attenuator/switch driver board (A5) indicate which test port is active.

5-2HP 8517B S-Parameter Test Set Manual