HP 181A Introduction, Table 6-1.Instrument this Guide Directly Applies To

6

Chapter 6 Backdating

Introduction

Introduction

This chapter contains information necessary to adapt this guide to apply to older instruments.

The backdating information includes the following:

∙ Backdating Hardware	page 6-3
∙ Backdating Firmware	page 6-8
∙ Backdating Specifications	page 6-16

Manual Changes

This guide applies directly to Counters with the following serial prefixes listed in Table 6-1.

Table 6-1. Instrument this Guide Directly Applies To

Instrument	Serial Prefix Number
HP 53131A Universal Counter	3711
HP 53132A Universal Counter	3710
HP 53181A Frequency Counter	3711

As engineering changes are made, newer instruments may have higher serial prefix numbers than the one shown on the title page of this guide. The guides for these instruments will be supplied with “Manual Updating Changes” package containing the required information. Replace the affected pages or modify existing guide information as directed in the pages of the Manual Updating Changes package. Contact the nearest Hewlett-Packard Sales and Support Office.

Older Instruments

To adapt this guide to older HP 53131A/132A/181A Counters having a serial prefix lower than 3711, perform the backdating provided in the following sections.

6-2 Assembly-Level Service Guide