Philips PM3320 Operating Manual page 183

8.1.1.3
8.1.1.4
8-5E
Description of accessories
Earth cable: To minimize ringing in a signal, an earth cable is provided. This cable must first be
plugged onto the probe body and then be connected to the nearest earth point of the circuit to be
measured.
Spring-loaded test clip: This is a provision for hands-free connection to a test point or
component lead.
Marking rings: At delivery a set of 3 different colour marking rings {red, white and blue) are
provided. This can be used to heip identify the specific probes when using more than one probe
on an oscilloscope.
Probe tip: A spare set of 2 probe tips are standard supplied with the probe. When a probe tip is
damaged it can be pulled out by means of a pair of pliers. Then a new tip must be firmly pushed in.
Insulating cap: An insulating cap is provided to cover the metal part of the probe during
measurements in densely wired circuits.
DLL. cap: This is a cap facilitating. measurements on dual-in-line integrated circuits.
Wrap pin adapter: The wrap pin adapter is a provision to make hands-free connection to a wire
wrapped pin circuit.
Earth bus: This is a provision to minimize ringing in VHF signals, when earthing must be as short
as possible.
Adjustments
Matching the probe to your oscilloscope
The measuring probe has been adjusted and checked by the manufacturer. However, to match
the probe to your oscilloscope, the following manipulation is necessary.
- Connect the measuring pin to the CAL-socket of the oscilloscope.
~ A trimmer can be adjusted through a hole in the compensation box to obtain optimum
square-wave response, see figure 8.3, 8.4 and 8.5.
Figure 8.3 Over~ Figure 84 Correct Figure 8.5 Under-
compensation compensation compensation