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Hallicrafters Items

 

Production year 1965 - 1969 at $19.95 

The Hallicrafters R-48 external speaker is an accessory that was offered by the company and is often found paired up with the Hallicrafters SX-111 or their SX-140 receiver. Although it will work with many of the other Hallicrafters receivers and those produced by other manufacturers. The R-48 employs an internally mounted elliptical shaped speaker which is of the permanent magnet moving coil design that measures five inches high by seven inches across. The speaker has a voice coil impedance of 3.2 ohms and is rated at five watts. Signals exit through a perforated grill section on the front of the unit. The R-48 is housed in a sturdy metal cabinet with rubber mounting feet.

The Hallicrafters R-48 external speaker included a crossover network that consists of an internally mounted capacitor and a rear mounted control switch. The operator has a choice of two settings which are labeled Voice and Fidelity. When the switch is set to the Voice position, the voice frequency range is accentuated. Placing the switch in the fidelity position reproduces the entire audio frequency range. The physical dimensions of the R-48 is 13 1/4 inches wide by 8 1/4 inches high by 6 1/2 inches deep. The 1/4 headphone jack at the lower right corner of the front panel and the RCA jack at the lower left hand corner of the back panel are not original to the unit and was added by a previous owner.

These speakers were an optional accessory that was not purchased in large numbers. Through-out the years they become lost or are discarded for a variety of reasons such as new technology takes its place, the receiver fails to operate, or the owner simply looses interest.  As such, it is not uncommon to find that these accessory items often command a premium in price. There are even a few models of these old speakers(not this model) that will fetch several hundred dollars at the auction sites.

The Hallicrafters R-48a external speaker which was produced between 1970 and 1972 is the same electrically as the R-48 speaker, but exhibits a few external changes in appearance and function. The Voice/Normal switch was moved to the bottom left hand corner of the front panel and the large round quarter sized Hallicrafters logo that is found on the face of the R-48 has been omitted on the R-48a. Other changes included a redesign of the bottom portion of the front panel and the rear corners of the back cabinet were not reinforced.

The photograph on the left is of the left side of the Hallicrafters R-48 external speaker. The picture on the right is of the bottom of the R-48.  

The photograph on the left is a close up of the internally mounted elliptical shaped speaker that is found inside of the Hallicrafters R-48. The back of the speaker has been stamped in black ink with the Hallicrafters logo and the part number of the speaker.

The picture on the right is of a paper sticker that is found on the inside floor of the R-48 cabinet. The sticker displays a schematic diagram of the R-48 circuit. A study of the schematic easily reveals the magic behind the crossover network employed in this Hallicrafters accessory.

  

  

Resources:

Radios by Hallicrafters with Price Guide by Chuck Dachis  

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