ARLA/CLUSTER: Os variados recetores para os radioamadores

[João Costa > CT1FBF]

Ham Radio Receivers

Ham Radio Receivers are designed and manufactured in handheld and
desktop versions, they differ in many ways offering features and
benefits to suit individual needs. A separate receiver covering the
Ham Bands you use on a regular basis is a useful addition to any shack
because it allows you to monitor your own transmissions.

I would suggest that you to look for a receiver that covers all of the
Short Wave bands and many give you coverage of the radio spectrum from
the long wave, and through the medium wave band, coverage starts from
around 150 Kilohertz through to 30 Megahertz.

New receivers offer the benefit of wide coverage, they incorporate the
Very High Frequency spectrum allocation and some continue coverage
through the Ultra High Frequency band. V.H.F. and U.H.F. contain
special allocations for Radio Hams to use and you will have the
advantage of being able to listen to local repeater stations which are
designed to extend the range of handheld transceivers.

All mode Ham Radio Receivers are in my opinion an essential
requirement, there is nothing more frustrating than finding a
transmission that you cannot resolve. Look for a receiver capable of
resolving Morse code, and single side band transmissions.

These modes of operation are usually described as C.W. and S.S.B., you
need L.S.B. and U.S.B., lower side band is used below 7 megahertz and
Upper side band above 7 megahertz. An anomaly in this rule is the 5
megahertz band where Upper side band is used by radio Hams for their
transmissions.

Other modes to consider are N.B.F.M, Narrow Band Frequency Modulation
is used on ten metres, the upper part of this band especially around
29 decimal six megahertz is used by repeaters. When conditions are
good on this band it is possible to listen to radio Hams communicating
with fellow enthusiasts between different continents.

Short wave receivers capable of resolving all of the modes of
transmission mentioned above can be extended to cover other parts of
the radio spectrum, by the use of frequency converters, used in
conjunction with the ten metre allocation at 28 Megahertz, frequency
converters are available to extend your listening entertainment, many
cover the Ham Radio two metre band, located at 144 Megahertz.

Building a frequency converter has additional benefits for the radio
enthusiast. Education is one of them, great satisfaction and a sense
of achievement is gained when you build an additional piece of
apparatus to extend your hobby. Buying second-hand converters and
modifying them to cover other allocations within the radio spectrum,
for example the Marine V.H.F. band, it is not only interesting it also
adds to your growing knowledge of how radio receivers work.

John Allsopp G4YDM
https://www.qrz.com/db/G4YDM

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