The R-390 is a double / triple conversion superheterodine receiver, designed by Collins and manufactured from 1950 to 1954. It uses a mechanical digital dial, has a PTO and supports AM and CW modes. It has 32 bands of 1MHz bandwidth each, covering from 0.5 to 32MHz. Its IFs are 9 to 18Mhz (only for 0.5 to 8MHz), 3 to 2Mhz and 455KHz.

Thanks to features such as a 6DC6 first RF amplifier, a suite of Military Grade Collins mechanical filters and full tracking RF and IF sections, the R390A is capable of copying signals down to its -143db noise floor, close to the galactic limit. All this while operating in …

R-390A/URR - Collins designed a replacement receiver that was introduced in 1954 with the designation of R-390A/URR. Though the new receiver looked very similar externally to the R-390, inside numerous changes were made to improve cost-to-performance and ease of maintenance.

2014年11月13日 · An EAC R-390A was my first 'true' boatanchor, and a huge step up from the Hallicrafters S-118 I'd previously been using to listen to shortwave (kinda like going from a Chevette to a Corvette, really).

My R-390A was built not by Collins, but Electronic Assistance Corporation (EAC), a division of Hammarlund, under a 1967 contract with the U.S. government. EAC made over 10,000 R-390As under their 1967 contract, and produced over 15,000 of them in total, more than just about any other R-390A manufacturer (even Collins, who produced surprisingly ...

Electronic Assistance Corporation (EAC) was the name of a subsidiary company operated by Hammarlund Manufacturing. EAC advertised a limited quantity of R-390A/URR receivers for sale to the public for $1,700 in 1970.The commercial specification appeared identical to the Military specification and these receivers were apparently excess from a ...

This receiver was a 1967 EAC R-390A that for some reason had an Imperial Electronics tag installed. Further inspection revealed that the receiver was nearly complete and original.

A large and very heavy metallic case that could be mounted on a rack, with a front panel and handles to lift it or insert it on a rack. The front panel has about 14 knobs, two dials, an analog frequency indicator, and two needle indicators for line and carrier level.

Over 55,000 R-390A receivers were manufactured by Collins, Motorola, Imperial, EAC, Teledyne, Stewart-Warner, Capehart, etc. from about 1954 to 1984. The R-390A is often considered to be one of the best vacuum tube general coverage receivers …

Welcome to the R-390 Series Frequently Asked Questions (FAQ) Page. The R-390A/URR radio receiver is arguably the best performing high-frequency (HF) receiver of the tube era. Its …