Can a P25 radio system be monitored with a scanner?

Yes, if the scanner has P25 decoding.

The P25 decoding came from APCO Project 25 of a trunked radio system, used as a standard for public safety communications.

The P25 uses radio wave frequencies from 136 MHz to 859 MHz, with the modulations of PSK, C4FM, or TDMA, and the mode of NFM.

Please see Sigidwiki site for the article Project 25 (P25)

Also, see The Radio Reference Wiki site for the article on APCO Project 25, especially the paragraph on Software Based Decoders.

For additional information, please see Jeffrey Kopcak site for the article P25 TRUNKED TRACKING AND DECODING WITH RTL-SDR, UNITRUNKER, AND DSDPLUS

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Which of the following answers is true?

The RF Power reading on a CDMA radio is not accurate on an analog power meter.

For more information, please see Electronic Design site for the article Watt’s My True RF Power? and also the article called Digitally Modulated Signals Challenge RF Power Meters

Also, High Frequency Electronics site for the article called Statistical Analysis for On-Site RF Power Measurement

And, Analog Devices site for the article Measurement and Control of RF Power (Part I)

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What is a common method used to program radios without using a “wired” connection?

Infra-red communication.

From wp2ahg:

Some radio transceivers can connect to each other using an infrared (IR) transmitter/receiver in order to clone the programming of one radio to another.

For more information, please see Rantec Microwave Systems article on The Different Types of Wireless Communication

Also, Electronics Hub site for the article on Wireless Communication: Introduction, Types and Applications

See, ElProCus Electronics site for the well-illustrated article on Different Types of Wireless Communication with Applications

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What is the common method for determining the exact sensitivity specification of a receiver?

Measure the recovered audio for 12 dB of SINAD.

A common method to verify performance of an analog receiver is to send the receiver an RF test signal consisting of a single audio tone with specific characteristics (e.g., deviation for an FM receiver). The audio output from the receiver is brought back into an audio input on the test system for measurement of SINAD, the ratio of Signal+Noise+Distortion divided by Noise+Distortion, expressed in dB. For public safety receivers, SINAD is commonly measured using a 1 kHz tone modulation. A 1 kHz audio notch filter in the test set is used to remove the tone from the received audio, the SINAD is then derived from the measurement ratio. Analog receiver sensitivity is measured by monitoring the SINAD level as the RF signal power is lowered. The RF input power resulting in 12 dB SINAD is typically considered the specified sensitivity of the receiver.

Receiver Testing with the Anritsu MS2830A Signal Analyzer, MG3710A Vector Signal Generator, and S412E LMR Master™

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A communications technician would perform a modulation-acceptance bandwidth test in order to:

Determine the effective bandwidth of a communications receiver.

For regulations covering this area, please see the Code of Federal Regulations, Title 47 Chapter I Subchapter A Part 15 - RADIO FREQUENCY DEVICES

As there are numerous references to testing, please use CTRL-F and search for the word "test." Please start the search at the Title 47 Chapter I Subchapter A Part 15 Subpart A § 15.31 Measurement standards.

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What is the maximum FM deviation for voice operation of a normal wideband channel on VHF and UHF?

5.0 kHz

From Electronics Notes site, article Ham Radio Frequency Modulation Use and see the paragraph Specifications for amateur radio FM operation

"The form of FM used for amateur radio communications is narrowband FM and for the VHF and UHF bands. A deviation of ± 5 kHz is normally the maximum and the channel spacing is dependent upon location. In the USA it can be 15, 20 or 30kHz dependent upon the region."

Please review the FCC site for the article Narrowbanding Overview

See Wikipedia's article Frequency deviation

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