Whilst dumpster diving, I happened upon a working HP 4953A Protocol Analyzer, circa 1987. I had no idea what it's for and planned to try & sell it, but I was wondering if there was any conceivable scenario where I might benefit from keeping it. What can it do for me?

 

Do you do any of this?
http://en.wikipedia.org/wiki/Protocol_analyzer

I never find anythig good, well, I found a pair of pliers once..

 

Yeah that wiki basically says the same thing as the intro paragraph of the HP manual. Can't you do that with a PC though? Can't a PC detect a protocol? The thing has a DB9 connector so it looks like I'm only going to be able to look at serial signals, not ethernet or USB or anything else. Not sure what use it really is...

 

If you ever have to work with unknown serial communications (RS-232) data and wanted to reverse engineer the command structure between two devices or on a network, you could use something like this.

This document pretty much says it all:

Hewlett Packard Journal, July 1985 (8.5MB pdf)
http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1985-07.pdf