B-Field Window

Shown above is a display of a properly tuned magnetic field. The Josephson peaks show up at n[Freq(GHz)/474], where n=1,2,3,4.
The line across the screen indicates the current SIS bias position.

This mode allows you to tune out the Josephson effect by adjusting the B-field on the junction in real time (by adjusting the current on the There are two polarities on the B-field bias box. Use whichever polarity nulls the Josephson effect most efficiently for minimum current through the magnet windings. Note that the Josephson effect shows up as a very spikey and erratic total power curve. Ideally the total power should look smooth (above), with only one real peak (though this is only really a on the 230 GHz receiver (See the for details).

It is absolutely essential for stable receiver operation that the Josephson effect be carefully nulled.

There are two ways to display the Total power as a function of bias.

Press Stop to return to the receiver control window.
| 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