Claims:

1 . A slide-screw tuner comprising a fixed ground, a mismatch probe and at least one linear actuator, and wherein: the mismatch probe is configured for movement in a first direction of signal flow along a transmission media and a second direction perpendicular to the signal flow, and whereby at least one of said first and second directions of movement is accomplished by the at least one linear actuator.

2. The tuner of claim 1 , wherein a first linear actuator is configured to move a carriage for motion parallel to the signal flow, and a second linear actuator is mounted on the carriage and configured to move the mismatch probe for motion perpendicular to the signal flow.

3. The tuner of claim 1 , further comprising at least one position sensor configured to measure the position in at least one direction of motion.

4. The tuner of claim 3, wherein motion in at least one direction of the mismatch probe is controlled with a servo system.

5. The tuner of claim 3, wherein at least one position sensor is an encoder.

6. The tuner of claim 1 , wherein at least one linear actuator is integrated with a position sensor.

7. The tuner of claim 1 wherein said at least one linear actuator comprises a piezo-electric actuator.

8. The tuner of claim 1 wherein said at least one linear actuator comprises a voice coil actuator.

AMENDED SHEET (ARTICLE 19) 9. The tuner of claim 1 wherein said at least one linear actuator comprises a linear motor actuator.

10. The tuner of claim 1 , wherein said mismatch probe is mounted to an arm that is spring loaded sideways against a side of the transmission media.

1 1 . The tuner of claim 1 , whereby the tuner is a small tuner configured to connect directly to a wafer probe when the wafer probe is connected to a DUT on the wafer, without interference with a microscope viewing the wafer to make the connection to the probe.

12. The tuner of claim 1 , wherein the tuner has a height dimension less than three inches.

13. The tuner of claim 1 , wherein the tuner is a high frequency tuner with a frequency range covering up to 26.5 GHz or higher.

14. A tuner comprising: a transmission media; a mismatch probe configured for movement in the direction of signal flow along the transmission media and perpendicular to the signal flow; and wherein the mismatch probe is held by an arm which is spring loaded sideways against a side of the transmission media.

15. The tuner of claim 14, wherein the transmission media is a slab line.

16. The tuner of claim 14, wherein the transmission media is waveguide.

AMENDED SHEET (ARTICLE 19) 17. A measurement system comprising: a slide-screw impedance tuner having a fixed ground, and that uses a linear actuator for at least one direction of motion.

18. The system of claim 17, whereby the tuner comprises one linear actuator configured to move a carriage for motion parallel to a signal flow, and another linear actuator is mounted on the carriage for motion perpendicular to the signal flow.

19. The tuner of claim 17, wherein at least one position sensor is used to measure the position in at least one direction of motion.

20. The system of claim 17 whereby the impedance tuner comprises a linear actuator integrated with a position sensor.

21 . The tuner of claim 19, wherein at least one position sensor is an encoder.

22. The system of claim 19 whereby at least one direction of motion in the impedance tuner is controlled with a servo system.

23. The system of claim 17 wherein the linear actuator of the tuner comprises a piezo-electric linear actuator.

24. The system of claim 17 wherein the tuner comprises at least one linear actuator which is a voice coil actuator.

25. The system of claim 17 wherein the tuner comprises at least one linear actuator which is a linear motor actuator.

AMENDED SHEET (ARTICLE 19) 26. The system of claim 17 wherein the tuner comprises at least one mismatch probe mounted to an arm that is spring loaded sideways against a side of a transmission media.

27. The system of claim 17 wherein the tuner is mounted with an orientation other than vertical.

28. The system of claim 17 whereby the system is an on-wafer measurement system, and wherein at least one tuner is connected directly to a wafer probe, whereby the tuner is a small tuner configured to connect directly to the wafer probe when the wafer probe is connected to a Device Under Test (DUT) on a wafer, without interference with a microscope viewing the wafer to make the connection to the probe.

29. The system of Claim 28, further comprising: an XYZ positioner; and wherein the impedance tuner and the wafer probe are mounted to the XYZ positioner to position the wafer probe relative to the wafer.

30. A slide-screw impedance tuner, comprising: a mismatch probe; a transmission media with a fixed ground; at least one linear actuator coupled to the mismatch probe; the mismatch probe configured for movement in a first direction of signal flow along the transmission media and a second direction perpendicular to the signal flow; and wherein at least one of said first and second directions of movement of the mismatch probe is accomplished by the at least one linear actuator.

AMENDED SHEET (ARTICLE 19) 31 . An impedance tuner according to claim 30, wherein the at least one linear actuator comprises: a first linear actuator configured to move a carriage supporting the mismatch probe parallel to the signal flow, and a second linear actuator mounted on the carriage and configured to move the mismatch probe perpendicular to the signal flow.

32. An impedance tuner according to claim 30 or claim 31 , further comprising: at least one position sensor configured to measure a probe or carriage position in at least one direction of motion.

33. An impedance tuner according to claim 32, wherein motion in at least one direction of the mismatch probe is controlled with a servo system.

34. An impedance tuner according to claim 32 or claim 33, wherein at least one position sensor is an encoder.

35. An impedance tuner according to any of claims 30, 31 , 32, 33 and 34, wherein at least one linear actuator is integrated with a position sensor.

36. An impedance tuner according to any of claims 30, 31 , 32 and 33, wherein said at least one linear actuator comprises one of a piezo-electric actuator, a voice coil actuator, and a linear motor actuator.

37. An impedance tuner according to any of claims 30-36, wherein said mismatch probe is mounted to an arm that is spring loaded sideways against a side of the transmission media.

AMENDED SHEET (ARTICLE 19) 38. An impedance tuner according to any of claims 30-37, wherein the tuner is a small tuner configured to connect directly to a wafer probe connected to a Device Under Test (DUT) on the wafer, without interference with a microscope viewing the wafer to make the connection to the probe.

39. An impedance tuner according to claim 38, wherein the tuner is a component of a measurement system which includes an XYZ positioner; and wherein the impedance tuner and the wafer probe are mounted to the XYZ positioner to position the wafer probe relative to the wafer.

40. An impedance tuner according to any of claims 30-39, wherein the tuner has a height dimension less than three inches.

41 . An impedance tuner according to any of claims 30-40, wherein the tuner is a high frequency tuner with a frequency range covering up to 26.5 GHz or higher.

42. An impedance tuner according to any of claims 30-41 , wherein the transmission media is a slab line.

43. An impedance tuner according to any of claims 30-41 , wherein the transmission media is waveguide.

44. An impedance tuner according to any of claims 30-43, wherein the impedance tuner is a component of a measurement system.

45. An impedance tuner according to any of Claims 30-44, wherein the

AMENDED SHEET (ARTICLE 19) tuner is mounted with an orientation other than vertical.

AMENDED SHEET (ARTICLE 19)