Radio although different in many respects to other electrical devices is still considered an electrical device. Amateur Radio Operators or Hams enjoy using a radio as a hobby.
We can talk to many different people in other Boroughs, Counties, States, Countries
and Continents and provide assistance in emergency situations.
Electrical power usually D.C is the main power force (EMF) used in radio.
Although AC (EMF) is generated and transmitted by the energy company and readily
available at the power receptacles it is used by the radio and converted into
D.C. power usually through a rectifier either by use of a Swithmode Supply
(Crowbar Power Supply) or Linear Power Supply (Standard rectifier using a diode
rectifier and/or Zener Diode and transformer). The Crowbar Rectifier also uses a
transformer. The explanation of Crowbar Rectification and Linear Rectification
is explained in the ARRL Handbook and not in this article. Power AC (EMF) is
generated and transmitted by the energy companies. The reasons for generating
and transmitting AC power and not DC Power have been the result of the theories
and proofs of the inventor of radio Nikola Tesla.
All Repeaters’ and radio transmitting stations have AC Power supplied to
their receptacles’. The radio can use a separate power supply or the power
supply can be built into the radio. NYC has a fragile power grid and a Black Out
is always imminent. Like Nat, KB2KLH says on the Big Apple Traffic Net. “When
the phones are down the hams are up” The ARES web site http://www.aresnyc.com
has a very applicable saying “when all else fails”. Hams, when a Black Out
occurs can either use a simplex frequency or if they have a gas generator or
Uninterruptible Power Supply they can remain on frequency and handle emergency
traffic. There is a way a ham can tell if a Black Out is imminent or if the
energy supply company needs to buy electricity from another power grid. The ham
monitors the line not with a voltmeter but with a frequency counter. If the
frequency is less then 60 Hertz by a few hundredths of a cycle like 59.97 the
energy supplier (Power Company) has trouble and if the frequency is more then
.03 of a cycle below 60 Hertz then the energy company is really in trouble
usually if power is unavailable from another power grid the energy company must
decrease their load (tell their customers to limit power use) or they will need
to lower their EMF output (Brown Out). Lowering their EMF will decrease the
current across their loads. The energy companies follow Ohms Law equations,
lowering their output EMF then less power is dissipated across their loads and
in essence is similar to reducing their power load. Ohms Law mathematics can
prove this theory. What the energy company doesn’t tell the customer that
lowering their EMF output will cause certain electrical devices to fail (not
radios) refrigerators and Air Conditioners most HVAC (Heating Ventilation& Air
Conditioning) technicians are aware of this as the compressors in these
electrical devices become defective when operated with lower voltage. This has
been the cause of many lawsuits by supermarkets. A Stripchart recorder
monitoring in this case the line voltage with a date and time stamp on it signed
by a licensed electrician then the individual energy customer can sue their
energy company for damages to their refrigerator, spoiled contents and their
defective Air Conditioners otherwise the energy user has insufficient evidence.
If the frequency is above 60 Hertz by a few hundreds or cycle like 60.07 then
everything is OK.