Receiver Control Window

Start Tuning the Receiver by:

  1. Select Closed Loop (press "CLSD L"), which will default to Constant voltage as shown on the screen above.
    NOTE: Constant current is not reccomended.
  2. Press the RX/DL button to switch from dummy load (DL) to receiver (RX).
    Important: Switch from Receiver mode to Dummy mode when finished observing.
  3. Set the SIS bias on the manual bias box of the appropriate receiver to approx 2.0-2.3mV.
  4. Tune up the LO in the usual way. If you are already tuned, you should see 7-11 uA of SIS junction current (displayed below the SIS bias voltage on the manual bias box, as well as on the hand held display/touchscreen above). If not, follow the procedure below.
  5. Put some current on the junction, 10uA would be typical.

  6. Press the button to apply magnetic field to the junction in order to suppress the Josephson currents.
  7. Press the button to check the junction sub-gap slope.
  8. Press the to have the computer set the IF output power to -9.5 dBm (+-1dB).
  9. Press the button to calculate the sub-gap resistance around the SIS bias point. This should be 160-400 Ohm.

    General Tuning Princials edited from Notes by Antony Schinckel

  10. Tuning the 230 GHz Receiver, General Principles
  11. Tuning the 345 GHz Receiver, General Principles
  12. Tuning the 492 GHz Receiver, General Principles
  13. Tuning the 650 GHz Receiver, General Principles

    | Receiver Index | Handheld Display Menu | Receiver Control Menu | B-field Menu | I/V sweep Menu |
    Web Page created and last updated on March 5, 2001, by Jacob W. Kooi