> I am in search of the schematic for the popular
> Hallicrafters SX-16 noise limiter modification. Mine > has the front panel switch (SW2) but nothing hooked to it.
> Thanks and have a nice day.
> Russ, KJ4BEB
Hallicrafters radios were built in the Chicago area, Electric Radio featured an article a few years ago revisiting the various company sites in the area over a 50 year period.
The Hallicrafters SX-16 is a Pre-WW2 short-wave receiver (1937), and was known as the Super Sky Rider.
Hallicrafters also ended up producing the SX-17 ... due to a special order SX-16 receivers by the FCC, that included the addition of this noise limiter. Amateur radio operators demanded access to these additions for their SX-16 receivers, so Hallicrafters produced the SX-17 model!
READ that STORY HERE:http://oak.cats.ohiou.edu/~postr/bapix/SX17.htm
SO, you really need to find the Hallicrafters SX-17 "Special Model" Super Skyrider schematic to find the noise limiter, that was only found on the special production SX-16 receivers.
The SX-17 has an added noise limiter switch on the front panel in the lower right corner.
Otherwise, the SX-16 and SX-17 have IDENTICAL front panels.
The SX-17 has 13 tubes compared to the SX-16 with 11.
The extra 2 tubes are the added 6K7 second RF stage and the
6H6 noise limiter. (An early version uses a 6J5 for the noise limiter.)
HERE is the Riders Volume 9, Hallicrafters SX-17 EARLY VERSION,
the Second Page of the PDF file shows the usage (change) to the later 6H6 tube usage.
You will see an X inside a circle, that is SWITCH 2 (SW2) -- your front panel switch!http://pdf.textfiles.com/manuals/SCA..._Scematics.pdf
SX-17 Service Manual is at BAMAhttp://www2.faculty.sbc.edu/kgrimm/b...r/hallicra.htm
Coverage for both models is from 540 KHz to 62 MHz in 6 bands. The upper band does not use the RF amp. Price for the SX-16 was $111 with crystal. Price for the SX-17 was 137.50 with crystal and $149.50 with the optional speaker. The "meter" to the right of center is the electrical bandspread scale which was advertised at "1000 degrees" (almost three rotations). The portion of the bandspread scale in use is highlighted with a moving pilot light, shown in the picture as a bright spot.
Contact Richard Post, KB8TAD for more information on this SX-16 addition.