5–36

**Rd **

**Cd **

**Cb **

Advanced Operation

The network source resistance. Only available when **Damped** termination is selected. The range is:

0.000Ω to 9.999TΩ default = 600.0Ω

The network source capacitance. Only available when **Damped** termination is selected. The range is:

0.000F to 9.999TF default = 4.700nF

The signal source DC blocking capacitor. Only available when

**Damped** termination is selected and **Direct/Blocked** is set to

**Blocked**. The range is:

0.000F to 9.999TF default = 1.000MF

**5.14 MULTI FREQ MODE **

This mode allows measurement of components at a number of user-defined frequencies. Limits can be turned off or set in absolute or percentage terms and can be different for each defined frequency. When limits are set in percentage terms, a nominal component value must also be entered. **MULTI FREQ** mode is divided into two areas: **MULTI FREQ – Set** and **MULTI **

**FREQ – Run**.

**5.14.1 MULTI FREQ – Set **

*Figure 5-40 MULTI FREQ – Set Display With No Parameters Set up *

Up to eight frequencies can be defined by highlighting the frequency, then entering the frequency with the data entry keypad. The and navigation keys scroll through each frequency in turn. Also available, depending upon the setting of the **Off Abs %** soft key, are

**High**, **Low** and **Minor** term limits and a **Nominal** parameter. The **High**, **Low,** **Minor** and

Advanced Operation 5–37

**Nominal** settings are accessed by pressing either of the or navigation keys when one of the frequency settings is highlighted. The **Nominal** value is common to all frequencies but the

**High**, **Low** and **Minor** term limits may be different for each frequency set.

Any limit set to zero is ignored when the multi-frequency test is run. Therefore either the major or minor term test may be omitted by setting the appropriate limits to zero.

**5.14.1.1 Example **

This example will illustrate the procedure for setting **MULTI FREQ** parameters using different limits for each set frequency. The sequence used in this example is not the only way to set the parameters but is intended to familiarize the user with this mode of operation. For this illustration, percentage limits will be used.

1) Enter **MULTI FREQ – Set** mode by pressing the **MULTI FREQ** soft key from the **MAIN **

**MENU**. If **MULTI FREQ – Run** mode is displayed, press the **SET** soft key. If no parameters have previously been set, the display will look like Figure 5-40 above.

2) If the test leads or fixture have been changed since the last time the analyzer was used, press the **CALIBRATE** soft key and perform the following trims with reference to sections

4.3 and 4.4.1. When finished, press the **MULTI FREQ** soft key to return to **MULTI **

**FREQ – Set** mode.

**O/C Trim (Pri) **

**S/C Trim (Pri) **

**HF Lead Compensation **

3) Use the **Off Abs %** soft key to highlight **%**. This sets the display ready to accept percentage limits.

4) Press the **IMPEDANCE** soft key. This will return the instrument to **IMPEDANCE **

**MODE** where the appropriate measurement parameters must be set prior to running a

**MULTI FREQ** test. Enter the parameters required for the test. For this example they are set to:

**AC Meas **

**L **

**Q **

**Parallel **

**1.00Vac **

**1.0000kHz**—this will be the first set frequency in **MULTI FREQ – Set** mode

**DC Bias 0.000 A OFF **

**NORM **

**Range Auto **

**Speed Med **

**ALC off **

**Note:** Where a component is to be measured over a wide frequency range, setting **Range** to

**Auto** is recommended.** **

When the measurement parameters have been set, press the **RETURN** soft key to return the instrument to **MULTI FREQ – Set** mode.** **

5–38

Advanced Operation

5) Highlight the first frequency, shown highlighted in Figure 5-40 (the and navigation keys scroll through each frequency in turn) and enter the required frequency with the data entry keypad.

6) Highlight and enter the next frequency. Continue to highlight and enter up to eight frequencies in this way. This example will enter frequencies of 1kHz, 3kHz, 10kHz, 30kHz,

100kHz, 300kHz and 1MHz.

7) With the first (top) frequency highlighted, press either of the or navigation keys until the **Nominal** parameter is highlighted (if using absolute limits there is no nominal parameter). Enter the **Nominal** value with the data entry keypad; for this example the nominal will be set to 100µH.

8) Still using the and navigation keys, highlight the **High** limit then enter the required limit with the data entry keypad. For this example all the limits will be set to ±10%, though they could be set to different values for each frequency. Highlight the **Low** limit and enter the required limit. Pressing the **Enter** key twice will echo the **High** limit but with the opposite sign.

9) Highlight the **Minor** term with the and navigation keys and enter the required value.

Note that the **Minor** term limit is either an upper or lower limit depending on what the parameter is (e.g. <D, >Q). For this example the Q term will be set to >2 at 1kHz, i.e. anything more than or equal to 2 will pass the minor term parameter and anything below 2 will fail.

10) Press the navigation key: the symbol will move down and point to the second frequency (3kHz in this example). Note that the limits showing at the bottom of the screen change as each frequency is selected in turn. Using the and navigation keys highlight and set the **High**, **Low**, and **Minor** limits for the second frequency. Press the navigation key again and the symbol will point to the third frequency and the limits for the third frequency can be set. Continue in this way until the limits have been set for each frequency.

The limits set in this example are as follows:

**(L) **

**Low Limit **

**(L) **

**Minor Term **

**Limit (Q) **

1kHz 10% -10% >2

3kHz 10% -10% >5

10kHz 10% -10% >20

30kHz 10% -10% >50

100kHz 10% -10% >50

300kHz 10% -10% >50

1MHz 10% -10% >50

These limits can be read back by selecting each frequency in turn.

Figure 5-41 shows the display when set to 30kHz in the example above.