Radio technology developed through the age of te crystal radio set, early vintage and antique radios using valves / vacuum tubes to more advanced ones, and then the ae of the transistor dawned. The equipment that was used in the 19th Century was crude and very insensitive, nowadays receivers are very sensitive and they offer many facilities. In 1895 Marconi demonstrated his first viable radio system, now more than a 100 years later the radios that are in use today bear no resemblance to the early equipment that was used. The history of the radio receiver is an integral part of the development of today's radio technology, and it is a fascinating story to see how we arrived at where we are today. Everything from broadcast radio and television through to mobile phones, wireless connectivity, Internet of Things and much more are based around radio technology. Radio technology is an integral part of everyday life. Radio history / timeline Radio receiver history Superhet radio history Classic vintage radio receivers Type - There are mobile, handheld, portable, in-vehicle, marine, and base station options available.History of the Radio Receiver History of the development of the radio or wireless radio receiver from the earliest antique radio sets using coherers, magnetic detectors, crystal radio sets, vintage radios using valves / tubes to modern high performance semiconductor based radios using digital signal processing and software defined radio techniques.Condition - There are new, used, and manufacturer's refurbished communications receivers available.Antenna - Choose a unit with a built-in antenna or a separate antenna.Power source - Choose electric-powered, battery-powered, or combination units.Brand - The available brands include Collins, Drake, Hallicrafters, Hammarlund, Heathkit, Icom, and Realistic.How do you choose a ham or amateur communications receiver? Backlit display - The display is lit from behind with an incandescent bulb.LCD - A liquid crystal display shows the band, mode, and channel.Antenna jack - A separate antenna jack allows you to attach a larger antenna.Digital tuning - This automatically scans for channels that are broadcasting.Portable - The communications receiver has a handle and is designed for portability.Some of the available features of affordable communications receivers on eBay include: What are the features of the ham communications receiver systems? The supported bands of broadcasting and receiving for these ham and amateur radio receivers include AM, FM, HF, UHF, and VHF. The supported modes of operation for the new and used communications receivers on eBay include AM and FM for traditional radio and CW and SSB for amateur and ham purposes. What are the supported modes and bands of communications receivers? Portable or handheld - These weigh approximately eight ounces and have a range of about five miles for sending and receiving signals.Shortwave radio - These shortwave radio communications receivers have a range of frequencies from 1.7 to 30 MHz, which is slightly higher than AM frequencies.They transmit over the full ham spectrum and broadcast for 200 miles. ![]() Mobile or in-vehicle - These receivers connect to an electrical outlet or a vehicle's battery by plugging in a cord to the cigarette lighter or a power adapter. ![]() It uses a 12-volt battery and transmits for thousands of miles.
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