Pager Testing Using the 8648A with an Internal Pager Encoder, Option 1EP:  Agilent Application Note   (added 6/06)

Paralleling RMS Converters Speeds Settling:  05/26/94 EDN-Design Ideas / (added 3/03) An RMS-to-dc converter requires an output lowpass filter, which sometimes leads to overly long settling times. Paralleling two converters reduces the circuit's settling time signal without increasing conversion errors Fig 1. The circuit in Fig 1 monitors 50-Hz mains. IC1, IC2, and their associated circuitry compose a phase shifter. The phase shifter has a 90° delay for 50-Hz inputs and constant gain. The second-order, lowpass, state-variable filter, IC5, sums and filters the outputs of RMS-to-dc converters IC3 and IC4....  

PC hardware monitor reports the weather:  01/18/01 EDN Design Ideas / (adds 08/05)  You usually use PC hardware monitors to keep a close eye on power-supply voltage levels, the speed of system cooling fans, and even the temperature of the CPU. Until fairly recently, this level of system monitoring was reserved for high-end servers running mission-critical applications. However, now that low-cost hardware monitoring AS ICs are available, advanced hardware monitoring has become a standard feature in most new PCs. And hardware monitors are now finding their way into diverse applications, such as weather stations (Figure 1).

PCB VSWR Bridge:  (schematic added 8/03)

Peak Reading Audio Level Meter:  indicates peak audio response on an analogue meter, similar to a tape recorder recording level meter (added 6/06)

Peak-reading meters:  (circuit / schematic design added 6/06)

pH Meter:  (schematic added 8/03)

Phantom Power Battery Test Circuit:  LED will light when battery is over42 volts   (added 5/02)

Phase Meter Operates to 10 MHz:  07)/04/96 EDN-Design Ideas / (added 6/06)

Phone line Voltage monitor meets FCC specs:  08/19/04 EDN Design Ideas  /  (added 1/05)  When you design equipment that interfaces to a phone line, it is often desirable to be able to monitor the dc voltage on the line. This ability can be useful, for example, to determine whether a line is in use before attempting to go off-hook and possibly interrupting somebody's phone call. FCC regulations place strict limits on the amount of leakage current an on-hook device can draw from a ph......

PIC Frequency Counter:  Programmable frequency meter with PIC16F84 and UPB1505 prescaler (circuit added 8/06)

PIC Logic Probe with Pulser:  (electronic schematic / circuit added 4/02)

PIC14C000 Calibration Parameter Theory and Implementation:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

PIC16F84 Based Diode Tester:  (circuit / schematic added 6/05)

Pink Noise Generator for Audio Testing:  (schematic added 8/03)

Polarity Detector:  This tester can be used to check the polarity of any power source, and is therefore very useful when installing automotive equipment, alarm systems or anything else you can think of. Because this circuit is so simple and cheap, even frying one with an over voltage is not a big deal.... (added 4/05)

Portable Temperature Monitoring Demystified:  App Note 1754: Maxim IC  (application note added6/06)

Power Chopper Tester:  (Circuit added 05/07)

Power-up Trouble Shooting:  Microchip Application Note Published 26-Aug-97   (app note added 2/06)

Pre Distortion Techniques:  Tape Linearizer and a Distortion Analyzer   (added 5/02)

Precision Digital Altimeter:  The current concept incorporates a wireless transmitter and receiver and is thought to be used for remote controlled airplanes or appliances with two separate parts. In other words, we have one dedicated transmitter (acquisition, filtering) and one dedicated receiver part (user-interface, look-up table, calibration, storage), capable of being connected together with any physical layer, e.g. wired, wireless, infrared. If you want to build a standalone altimeter/variometer just for hiking or mountaineering, this setup can obviously be simplified by omitting the wireless components.... (added 4/05)

Precision Wideband Current Probe for LCD Backlight Measurement:  DN101  Design Notes (Linear Technology) (app note added 1/06)

Procedure for DDR Clock Skew and Jitter Measurements:  Pericom Semiconductor Application Note # 028 (app note added 2/05)

Procedure Tests Transducer:  03/01/96 EDN-Design Ideas / (added 2/06) 

Product Environmentals and High Reliability Testing:  Application Note MiniCircuits.com  (app note added 6/06)

Pulse Generator and Signal Tracer:  Dual-purpose test-instrument Very simple Circuitry,1.5 Volt  Battery-operated  (added 09/05)

Pulse Generator Verifies Test Setups:  05/26/94 EDN-Design Ideas / (added 6/06) Verifying the rise-time limit of wideband test-equipment setups is a difficult task. In particular, you must often know the "end-to-end" rise time of an oscilloscope/probe combination to ensure measurement integrity. Fig1s circuit provides an 800-psec pulse having rise and fall times shorter than250 psec. The pulses amplitude is10V, and the circuits source impedance is50 Ohm.....

Pulse Reading Logic Probe (solorb):  (electronic diagram added 6/03)

Pulse-Generator Signal-Tracer:  Dual-purpose test-instrument Very simple circuitry, 1.5V Battery-operated (added 9/04)