This is what HP called a "Communications Test Set", and Motorola called a "Service Monitor". It is used for the alignment, checkout and repair of radio equipment. These were used in radio service shops (newer versions are still used). I used this to work on Amateur Radio equipment. This will work with AM, SSB, CW, FM, PM, EDACS, LTR. It also handles both analog and digital subaudible tones (CTCSS and DCS).
Here is a YouTube playlist, that tells you how to use this:
https://www.youtube.com/playlist?list=PL1VjuDYXe8IRI_M1nELbsoMRVByoYOrID
It covers a frequency range of 400 kHz to 1 GHz, so is good for just about any radio equipment. The 60 W input attenuator is installed. This is rated for 60 W continuous, 100 W for short intervals. The screen has no burn-in at all. Unlike the 8920A, this has a standard PCMCIA slot, and more memory. Serial and HPIB ports are on the back.
The list of options:
001: High Stability Timebase
004: Tone/Digital Signalling
013: C-MSG Filter
014: 6 kHz Bandpass Filter
055: Mechanical Attenuators (This allows 400 kHz-1 GHz operation. The standard attenuators only do 10 MHz-1 GHz.)
102: Spectrum Analyzer
103: Tracking Generator
If you are familiar with the HP 8920 family of instruments, you'll know that this one has all of the desireable options installed.
The HP 8920B is in excellent condition. I periodically check the accuracy of the unit against other equipment, and it is well within spec. The carry handle and snap-on lid are included.
I also have a 4 MB Flash card with AM Tests, FM Tests, RF Tools, and EDACS Tests on it. In addition, a 2 MB SRAM card for external data storage or backup.
Also included is an Amtronix SW2012N return loss bridge that covers 0.5 - 1500 MHz. Two low loss coax cables come with the RLB. This is like new.
Condition of the HP 8920B is excellent. All of the above for $3000. The price is firm. ebay prices are much higher.
As an extra, I will throw in several Midland VHF mobile radios. These are ex-police radios that can easily be re-tuned and programmed for Amateur use (I had done several in the past). Included with the radios is a laptop with programming software, and various programming interfaces/cables. I have software and cables for more than just these Midland radios.