Vintage Audio: Wilkinson Transmitter Extension Meter
This chapter of Found in the Attic explores a forgotten chapter in the history of broadcast remote control technology, transmitter extension meter panels.
In the earliest days of radio, the Commission required all operating transmitter sites to be manned by someone with a First Class FCC license. That person was required to take meter readings every 30 minutes, maintain the transmitter log, and make repairs, or switch to a backup in the event of failures.
As technology evolved, and transmitters became more reliable, the rules were relaxed so that sites could be controlled remotely. In FCC lingo, the studio where the operator on duty was stationed was known as the control point. They Commission allowed most stations to have operators with a Third Class license and broadcast endorsement on duty. There were exceptions for directional stations, and those with higher power, which still required the First Class ticket.
Read MoreTopics: Vintage Electronics, Vintage Technology
Vintage Audio: Hallicrafters S-20 'Sky Champion' receiver
This installment of Found in the Attic examines the Hallicrafters S-20 'Sky Champion' receiver. The 'Sky Champion' line was the company's' mid-priced communications receiver. Introduced in 1938, the S-20 was replaced by the S-20R in 1939. Since it was in production for less than a year, these receivers are somewhat rare.
There are several differences between the S-20 and S-20R. The S-20 primarily used tubes with grid caps, while the later S-20R used newer replacements. Tube lineup for the S-20 includes: 6K7, RF stage; 6L7, 1st detector-mixer; 6J5, HF osc; 6K7, IF amp; 6Q7, 2nd detector-AVC-1st audio stage; 6F6, audio out; 6J5, BFO and 80, rectifier.
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Vintage Audio: Zenith Allegro Modular Stereo
The 1970s saw the music industry grow in to a multi-billion dollar business. This explosive growth was one of the driving forces behind a comparable expansion in consumer electronics, and in particular, hi-fi gear.
Component stereo gear was the bread and butter of companies such as Pioneer, Marantz and Denon. Consumers could purchase tuners, amps and tape decks at a price point they could afford, and upgrade as new technology and/or larger paychecks became available. At the other end of the spectrum were modular stereo systems. These devices usually had all of the above components, along with a turntable, in one chassis. Since all of the electronics were usually on a single motherboard, and there was only one chassis, they could be manufactured fairly inexpensively. There were two varieties of modular stereos. The large cabinet systems found in virtually every living room during the 1970s was one type, and there were also tabletop units.
Read MoreTopics: Vintage Electronics
NuTone 2067B-2068B Transistor Radio-Intercom System
Radios come in all shapes and sizes, and this column seeks out some of the forgotten and unusual examples. Previous installments have examined farm radios, unlikely portables and early clock radios. This time around, we'll look at the NuTone 2067B transistor radio intercom system. It dates to 1965, when home radio-intercoms were something of a status symbol in larger houses.
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