The computer is used as the processing control center, and the electronic screen and the computer display (VGA) window correspond to each other point by point, and the display content is synchronized in real time. The display map position is adjustable, and the size of the display screen can be arbitrarily selected. The display information can be edited, added, deleted, and modified by different input means such as keyboard, mouse, and scanner. The playing program is stored in the control host, and the program playing sequence and time are realized to be integrated and alternately played, or may be superimposed on each other.
Crown gold Φ5 indoor monochrome LED display 
Crown gold Φ5 indoor monochrome LED display <br> Specifications: Φ5
Display base color: 1R
Pixel composition: Red life: 100,000 hours Other performance Pixel density: 17222 points / m2
Indoor monochrome:
The indoor monochrome LED display system is mainly composed of a microcomputer, a control part and a display part. During use, the user transmits the edited image text and corresponding control commands to the control part of the display system via the communication card on the microcomputer through the control software, and the display part can display the user edited page by page according to the display mode selected by the user. Image text.
The indoor monochrome LED display system also has a unique offline display. In this way, after the user has transferred the content to be displayed to the display portion, the computer does not have to continue to intervene in the display process, and the display system can display the information to be displayed according to the mode set by the user. The indoor monochrome LED display produced by our company can display various graphics, texts and other information. The surface is flat, the display is uniform, the brightness of the light is good, the display effect is clear and stable, and there are more than ten kinds of cyclic changes. It adopts long-distance serial communication and can be operated offline with power-down protection. All are assembled with high-brightness luminous matrix modules and imported components. It has high brightness, wide vision, long life, light weight, modular structure, easy installation and easy maintenance.
A siren is a loud noise-making device. Civil defense sirens are mounted in fixed locations and used to warn of natural disasters or attacks. Sirens are used on emergency service vehicles such as ambulances, police cars, and fire trucks. There are two general types: pneumatic and electronic.
Many fire sirens (used for calling the volunteer fire fighters) serve double duty as tornado or civil defense sirens, alerting an entire community of impending danger. Most fire
sirens are either mounted on the roof of a fire station or on a pole
next to the fire station. Fire sirens can also be mounted on or near
government buildings, on tall structures such as water towers,
as well as in systems where several sirens are distributed around a
town for better sound coverage. Most fire sirens are single tone and
mechanically driven by electric motors with a rotor attached to the
shaft. Some newer sirens are electronically driven speakers.
Fire sirens are often called "fire whistles", "fire alarms", or
"fire horns". Although there is no standard signaling of fire sirens,
some utilize codes to inform firefighters of the location of the fire.
Civil defense sirens also used as fire sirens often can produce an
alternating "hi-lo" signal (similar to emergency vehicles in many
European countries) as the fire signal, or a slow wail (typically 3x) as
to not confuse the public with the standard civil defense signals of
alert (steady tone) and attack (fast wavering tone). Fire sirens are
often tested once a day at noon and are also called "noon sirens" or
"noon whistles".
The first emergency vehicles relied on a bell. Then in the 70s,
they switched to a duotone airhorn. Then in the 80s, that was overtaken
by an electronic wail.
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