Ramsey Electronics SR-1, Instruction Manual

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SR-1 – 4
INTRODUCTION TO THE SR-1
The SR-1 is a single-conversion superheterodyne receiver designed specifically
for listening to AM broadcasting stations in the range of 4 to 10 Mhz. Because
of this "superhet" design, your favorite foreign broadcasting services will come
in loud and clear, with pleasing audio sound quality, with a minimum of
overload, frequency drift or heterodyne whistles. Because of this broadcast
oriented design, other shortwave signals such as Morse code (CW), single-
sideband (SSB) voice communications and some Teletype signals will usually
sound like garbled hisses. On the other hand, similarly inexpensive receivers
designed for CW and SSB can give only marginal performance in receiving
broadcast stations due to the lack of superheterodyne design. For example, our
popular Ramsey direct-conversion receivers for the 80,40,30 and 20 Meter
Amateur bands will also pick up AM broadcast stations, but you'll mainly hear
their strong AM "carrier" signal due to the lack of the superheterodyne circuitry.
Even if such a carrier is tuned to a "null," listening fidelity is less than desirable.
WHAT YOU CAN EXPECT TO HEAR
First, let's take a look at what is POSSIBLE to hear on your SR-1. The
following are the international shortwave broadcasting bands within its tuning
range:
4.750-5.060 Mhz. (Lower power, regional "tropical" broadcasting)
5.950-6.200 Mhz (Late evening)
7.100-7.300 Mhz. (Late afternoon, early evening) (This band is always shared
with the 7.0-7.3 Mhz Amateur Radio Band)
9.500-9.900 Mhz. (Always "something" on, 24 hours a day!)
Especially strong signals include these, among others:
•
BBC London: an intelligent perspective on world affairs