Nice Singer Metrics Division / Empire Model NF-157 (S/N# 326) Broadband Power Density Meter. This system consists of a basic Measuring Unit BA-157 (S/N# 326), a Low Frequency probe Model PR-1-157 (S/N# 326)used for measurements from 200MHz to 800MHz (includes tuning scale), a Medium Frequency horn PR-2-157 (S/N# 326) used for measurements from 750 MHz to 4,000MHz, and a High Frequency Horn Model PR-3-157 (S/N# 326) used for measurements from 3,750MHz to 10,000MHz. Also included are a very sturdy carrying case (AC-157) and a RF cable (CB-157) to connect the Measuring unit to the antennas. An original copy of the operating and maintenance manual with schematics IS INCLUDED. Please note the following: The panel meter’s glass is broken.  Also the COVER for the Basic Measuring unit is MISSING. The battery box is complete and there are 2 wires (Red & Black) under the cover that can be used to connect it to an external power source or they can be removed if one can find a suitable battery for the unit.  It operates on 15 Volts DC. The inner and outer batter covers ARE included and installed.  The meter is a linear scale 200uAdc Meter (68-Ohm).  One should be able to replace it with a suitable round meter which is usually available on eBay but is NOT INCLUDED. We have not tested this equipment. Neither have we determined if the panel meter in the BA-157 is functional or not. 

Here is a description of the purpose of this equipment taken from the operating manual:  Broadband Power Density Meter Model NF-157 is designed to measure average power density from 1.0 milliwatts per square centimeter midscale to 2000 milliwatts per square centimeter over the frequency range of 200MHz to 10,000MHz, and may be used for either CW or pulse modulated signals.  The equipment is intended for use in the probing of high density RF fields to determine the location of hazardous areas.  It may also be used for the detection of hot spots and leakage near an antenna and other high power components.

This information is a best effort so BID ACCORDINGLY. These items appear to be in good+ overall physical and cosmetic condition except as noted above (damaged meter). As we are unable test them to specification and due to fact that they are at least 50 years old, I am selling them for PARTS or REPAIRS per eBay protocol and as USED, strictly AS-IS. The pictures form part of the description.  I ship within 3 days of receipt of funds.