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Because of these characteristics, AN/ARC-5 close equivalents to the control boxes of the ARA/ATA and SCR-274-N are rare or never existed. The most common AN/ARC-5 receiver remote control box is the C-38/ARC-5, which allows control only of audio volume of the VHF and MF/HF receivers. No power, mode, or frequency controls are present.
Arc welding power supplies can deliver either direct (DC) or alternating (AC) current to the work, while consumable or non-consumable electrodes are used. The welding area is usually protected by some type of shielding gas (e.g. an inert gas), vapor, or slag. Arc welding processes may be manual, semi-automatic, or fully automated.
Most ground SINCGARS have the capability to control output power; however, most airborne SINCGARS are fixed power. Those RTs with power settings can vary transmission range from approximately 200 meters (660 feet) to 10 kilometers (km) (6.2 miles). Adding a power amplifier increases the line of sight (LOS) range to approximately 40 km (25 miles).
In higher-quality units an alternator with more poles is used and supplies current at a higher frequency, such as 400 Hz. The smaller amount of time the high-frequency waveform spends near zero makes it much easier to strike and maintain a stable arc than with the cheaper grid-frequency sets or grid-frequency mains-powered units. [citation needed]
A transformer-style welding power supply converts the moderate voltage and moderate current electricity from the utility mains (typically 230 or 115 VAC) into a high current and low voltage supply, typically between 17 and 45 (open-circuit) volts and 55 to 590 amperes.
Maintaining a short arc length, while preventing contact between the tungsten electrode and the workpiece, is also important. [13] To strike the welding arc, a high-frequency generator (similar to a Tesla coil) provides an electric spark. This spark is a conductive path for the welding current through the shielding gas and allows the arc to be ...
The International Institute of Welding Technology IIW published the Guideline "Recommendations for the HFMI Treatment" [3] in October 2016. An overview of higher frequency hammers (HFMI) is presented, and recommendations for the correct application of the method and quantitative measurements for quality assurance the guideline provides the basis for measurements of HFMI improved welded joints ...
The ARC-190 is a military HF radio that operates between 2-30 MHz and transmits at 300+ watts.It features a dual heterodyne receiver/transmitter that uses IF frequencies of 97.8 and 1.8 MHz, an antenna coupler that is pressurized to 7±1 PSI with dry nitrogen (air) which (1) prevents high voltage arcing, (2) prevents corrosion, (3) provides a uniform cooling medium, and one of various controls ...