Circuit Description

The input signals are obtained from the four storage decades of the counter. A digit-selector switch permits selection of the first three, or the last three, or the last two digits to be recorded, ff three digits are recorded, the output increments are 0.1 each. For two digits, the increments are 1 each. The output is either 1 ma for galvanometer recorders, or 100 mv for potentiometer recorders. Figure 0 is a simplified schematic diagram of the converter. Twelve input lines (4 for each decade)...

Of Operation

Figure 3 is a combined block and ele mentary schematic diagram. The input signal is clipped or limited, amplified, clipped a second time, and amplified again. The resulting wave-shape approximates a square wave or a series of pulses, depending upon whether the input signal is a sine wave or pulses, respectively. The pulses trigger a Schmitt circuit, which produces positive pulses of 0.1- xsec duration, coinciding in time with the positive-slope zero crossings of the input signal. These pulses...

Remote Control For Variac Autotransformers

Motor-driven Variac autotransform-ers are often positioned from a pushbutton control. The push buttons operate a two-phase motor to change the Variac setting and a voltmeter is used to indicate the output voltage. While this system provides the utmost in simplicity and reliability, the meter ballistics and the reaction time of the operator require that the motor drive be slow. Otherwise, considerable difficulty is experienced in adjusting to the desired output voltage. A new device, the Type...

Type B Syncronometer

Input 1000-cycle sine wave, one volt into 50,000 ohms.' Contactor Stability Maximum contact closing time deviation at any microdial setting is 0.1 msec. Calibration Errors The maximum deviation between the indicated microdial setting and the actual contactor closing time varies sinusoidally from 0 to 1 msec over the 1000-msec range. Accuracy of Time Increments The maximum error over a time interval of 25 msec is 2 0.1 msec. Power Input 105 to 125 (or 210 to 250) volts, 50 to 60 cps 22 watts,...

Type B Frequencymeasuring Equipment

Measurements of unknown frequencies in terms of a locally generated standard frequency are being made more and more with digital counting equipment, and the Type 1113-A Standard- l3The closing time is used for reference because of its inherently greater reliability. For a description of use of the Syncronometer see F. D. I ewis, Standard Time Signals. General Radio Experimenter, Vol. 32, No. 13, June, 1958. Frequency Oscillator and the Type 1130-A Digital Time and Frequency Meter have been...

Uses

The high sensitivity, low noise level, and continuous-tuning features of this instrument foster a wide variety of uses. Figures 3, 4, 5, and 6 show the selectivity, response and noise characteristics as functions of frequency. The above combination of features makes possible extremely precise bridge settings, even with very low-power generators, at any frequency in the audio range. Provision for logarithmic response makes adjustments of generator level unnecessary. The new General Radio meter...

New Dynamic Microphone System

The Type 1500-P12 Dynamic Microphone System replaces the older Typk 759-P25 Dynamic Microphone and Accessories' as a high-quality acoustic pickup system for sound-level meters, analyzers, graphic level recorders or tape recorders. This new microphone system, illustrated in Figure 1, includes the Type 15fiO-P2 Dynamic Microphone, 'A I )ynamic Microphone for the Sound-Level Meter, (ienenil H'ulin Experimenter, Vol. XXV, No. 11. April 1951. the Type I5f> 0-P22 Microphone Transformer, the Type...

Tuned Amplifier And Null Detector With Onemicrovolt Sensitivity

The Type 1232-A Tuned Amplifier and Null Detector is a sensitive, low-noise, transistor amplifier, which tunes continuously from 20 cps to 20 kc, with additional fixed-timed frequencies of 50-kc and 100-kc. It is intended primarily as a bridge detector but has many other important uses, among them the detection of high-frequency modulated signals with a crystal demodulator , approximate wave analysis at audio frequencies, and as a preamplifier for transducers. The outstanding characteristics of...

Specifications

Frequency Characteristics Any one of four response characteristics, A, H, C, or 20 kc, can be selected by a panel switch. The A, B, and C weighting positions are in accordance with American Standard Association specifications on sound-level meters. The 20-kc position allows the use of the complete frequency response of the sound-level meter's amplifier, which is flat from 20 cps to 20 kc, so that complete use can he made of wide-range microphones such as the General Radio Tyi'K 1551-P1...

Info

Of four circuits can be formed from the circuits of Figures 5 and 6. These circuits have the same tuning laws. These frequency bridges all have three complex bridge arms. A simpler arrangement for use in feedback circuits is to have two arms of the bridge consist of a fixed voltage divider. The other two arms of the bridge are formed by a three-terminal network whose output voltage is equal to that of the divider at some frequency, as in the familiar

The Type A Vibration Meter

The new General Radio Vibration Meter, Type 1553-A, is a portable easy-to-use instrument for the quantitative measurement of vibration. With its aecelerometer, the Type 15G0-P51 Ceramic V ibration Pickup,1 it is direct reading in acceleration, velocity, displacement, and jerk. Other pickups can also be used, among them velocity-type transducers and special-purpose accel-erometers responding to frequencies up to 20 kc. With many of these, the vibration meter can be adjusted to be direct reading....

Sixdial Decade Resistor

View of the Type 1432-X Decade Resistor. General Radio decade resistors are stable, accurate units designed for use at audio and radio frequencies as well as at dc. Available in single decades or in multi-dial boxes, they have been manufactured continuously since 1915. The design and construction of the resistors are constantly being improved, as new materials and production methods become available, and new combinations of decade units in the Type 1432 assemblies are made available...

Prlt

50-ohm Rigid Air Line 50-ohm Rigid Air Line locking RG-58 U, RG-58A lT Cables RG-59 U, RG-62 U Cables nonconstant impedance RG-58 1, RG-58 A I Cables RG-59 L RG-62 C Cables nonconstant impedance 874-A2 Cable RG-8 U, RG-9 LT, RG-110 LT Cables 874-A3, RG-29 U, RG-55 IT, RG-58 U, R G-58A 1 Cables RG-59 L, RG-62 1 f ables nonconstant impedance 874- 2 Cable R -8 LT, RG-9 L, RG-116 lT Cables 874-A3, RG-29 U, RG-55 V, RG-58 , RG-58 A I Cables RG-59 U, RG-62 C Cnbl 874-A2 Cable RG-8 U, R lt -9 U,...

T

Elementary schematic of the 5 1 regenerative divider. which is available at the output terminal. The choice of a regenerative divider from 5 Mc to 1 Mc and switching dividers for the lower frequencies was dictated by twTo considerations The use of a regenerative divider above 1 Me is more economical, while below 1 Mc switching dividers have better phase stability. An important objective of this design has been to obtain high-phase stability so that the output signals can be used for...

The Type A Uhf Oscillator

Panel view of the Type 1361-A UHF Oscillator. Figure 1. Panel view of the Type 1361-A UHF Oscillator. Many laboratory and production-line tests require a compact signal source which can deliver more output than the average standard-signal generator, while not requiring an accurate calibration of absolute output level. Measurements with the Type 874-LBA Slotted Line, the Type 1602-B UHF Admittance Meter, the Type 1607-A Transfer-Function and Immittance Bridge, as well as the Type...

General Radio Demonstrates Traveling Exhibit At Paris Seminar

The General Radio traveling exhibit is demonstrated to export sales representatives by Peter J. Macalka, At the second biennial General Radio resentatives for France and the French overseas sales and engineering seminar, colonies, the seminar included both a new traveling exhibit of General Radio products was demonstrated to more than 40 engineers and export sales representatives from 16 countries. Held in Paris at the offices and laboratory of Etablissements Radiophon, General Radio rep- The...

Testing Of Solidstate Diodes At Megacycles

One of the basic measurements required in the manufacture of solid-state diodes is the determination of the rectification efficiency. JAN specified procedures call for a 100-Mc signal to be fed through the diode into a prescribed RC load. The resulting load voltage is a measure of the rectification efficiency. Rheem Semiconductor Corporation, Mountain View, California, thoroughly studied various methods of making the required test and developed an assembly that permits the testing-sorting...

General Radio Syncronometer Model 1103-a

Synchronous Hour Clocks

Block diagram of the switching divider. Figure 12. Block diagram of the switching divider. frequency standards. Time is a fundamental dimension in our physical descriptions of things, and the need for more and more accurate measurements of time has steadily increased over the years. A frequency standard, which generates a series of events at a very constant rate, can be considered as a linear interpolator between measured times that mark the beginning and end of time intervals. To...

Frequency Counter With A Memory And With Builtin Reliability

What, another counter Yes, the Type 1130-A Digital Time and Frequency Meter shown in Figure I is a brand-new entry in the field of highspeed counters new on the scene and new in many important details. Like several others, it is an automatic instrument for the precise measurement of frequency, period, and time intervals. It differs from them, however, in using new circuits and new design ideas to provide unusual features and a very high degree of reliability. from de to 10 Mc with a maximum...

New And Improved Precision Capacitor

Panel view of the new Type 1422 Precision Capacitor. Note the large, transparent flange on the control knob, which greatly facilitates precise setting. There are many readers of the Experimenter who will have no difficulty in recalling, in a nostalgic moment, the consistent proud contention of the makers of the Dodge automobile in the 1920's that they made no yearly models, only continuous improvements. Such a description might with equal truth be applied to the history of precision...

Hermaphrodite Connectors Versus Plugs And Jacks

'New and Improved Coaxial Connectors. OfBfraJ h'udio tSxperimrnter, 3. gt . 10, October, 1961, hermaphrodite connector into a well-established world of male and female connectors. It certainly was easier, though, than if the situation had been reversed, and plugs and jacks were trying to gain acceptance against the established convenience of hermaphrodite connectors. The plug-and-jack system for power connections has an essential, practical advantage in terms of safety, but the carry-over of...

Tuderegulating Supply

Type 1750-A Sweep Drive for sweep-frequency measurement techniques. A new model is now available, Type 12G3-B, which has similar characteristics to its predecessor. It can be used with the Sweep Drive as well in circuits where the oscillator frequency is changed manually or by means of the Type 907-R and 908-R Dial Drives. A feature of the new model is provision Figure 1. Panel view of the Type 1263-B Amplitude-Regulating Power Supply. for square-wave modulation of the oscillator at 1,000 cps....

Contents

Type 1551-C Sound-Level New Dynamic Microphone System 7 A New and Improved Precision Capacitor 10 Improvements in the Vacuum-Tube Bridge 19 Local Exhibits Syracuse to Washington, D. C 19 Bargain Sale The General Radio EXPERIMENTER is mailed without charge each month to engineers, scientists, technicians, and others interested in electronic techniques in measurement. When sending requests for subscriptions and address-change notices, please supply the following information name, company address,...