new SP-400 is four radios in one
The new handheld performs the functions of a
pile of different boxes
By J. Mac McClellan
Sporty’s new SP-400 handheld radio is a
com transceiver, of course, allowing you to communicate across the
entire ATC frequency band. It also can receive and display VOR radials,
and ILS guidance, including the glideslope. And it can also receive NOAA’s
dedicated weather channels.
Do you realize what a technological
achievement that is? Those tasks represent four distinct receiver
functions, and there is also the transmitter to send your words to the
controllers. To deliver so much capability in a compact handheld
transceiver that costs only $399 blows me away.
Consider that ATC communications operate
across a section of the VHF radio band, and so do the VOR/LOC signals
and the broadcasts from the NOAA weather stations. Sounds like a single
receiver function, right? Wrong. These are four different operations.
First, the com part of the SP-400 operates on AM, which is unique to
aviation. Virtually all other radio communications use FM techniques. So
the AM broadcast and reception from the controllers is one function. But
the NOAA weather channels broadcast in FM, so the SP-400 needs to be
able to perform as an FM receiver.
We usually lump VOR and localizer
functions together because those signals are adjacent to each other on
the VHF band. But once the signals are received something called a VOR/LOC
conversion needs to happen so that the different modulations of the VOR
versus the localizer and be presented as either a radial to or from the
station, or as the single center line guidance of a localizer. Not long
ago a VOR/LOC converter was a separate avionics box that you had to buy,
and then mount in your airplane.
Finally, the glideslope signal is in the
UHF band and that requires still another receiver technology. Glideslope
receivers have stood alone for decades, and many a well-equipped
airplane had only one even though there were two VOR/LOC receivers. To
get a glideslope receiver in a little handheld, and for so little money,
So, with the SP-400 you have complete IFR
backup capability that is independent from the airplane electrical
system and its antennas. You can talk to the controllers, track a radial
to or from a VOR, and then in an emergency have ILS guidance to the
The flat screen display on the SP-400
measures about two inches by two inches allowing plenty of room to show
frequencies, radials and other information large enough that I don’t
need my reading glasses to see them.
A vertical bar moves left or right to
show course deviation from a selected radial or the localizer. A
horizontal bar moves up or down to show glideslope deviation. In other
words, it’s a conventional ILS display – except it is in a handheld
Despite the complexity of its
multi-receiver functions using the SP-400 is as intuitive as any piece
of avionics that I have encountered. To select a frequency simply key in
the numbers using the telephone style keypad. The only trick here is to
fill out all of the numbers. So, to enter 126.4, you would key in
126.400. You can also use keys marked “DWN” and “UP” to step
through frequencies. Press and hold the button marked 121.5 and up comes
the emergency frequency. The recall key displays a list of frequencies
you have stored in memory.
When a VOR is received you see your bearing to the station. To enter a
radial you hold down the OBS button. The SP-400 recognizes a localizer
frequency, and the paired glideslope if there is one, without any
special action other than entering the frequency.
Somehow the SP-400 receives the nav
signals with good accuracy using only a “rubber ducky” type of
antenna that looks much like that used on an ordinary handheld com.
Obviously there is a lot going on inside that antenna, and the receiver
itself, to perform all of the functions that require their own dedicated
antennas on an airplane.
Standard power for the SP-400 is eight AA
alkaline batteries though rechargeable batteries are an option, or you
can connect to aircraft power. I like alkaline batteries for the
emergency standby radio because their shelf life is years while the
rechargeable batteries fade even when not in use. Also, it’s easy to
carry along a spare set of alkaline batteries without worry they will
discharge while waiting for you to really need them. A battery life
indicator continuously displays how much power you have left.
An option that I would want is the $26
headset adapter so you can plug in your standard headset. The speaker
volume of the SP-400 is good enough to hear in a noisy cockpit, but in a
true emergency loss of primary avionics I would want the advantage of
the normal headset.
Finally, Sporty’s SP-400 comes with a
You can find Sporty’s Pilot Shop here
at the show in Building D, booth numbers 4128 to 4130. For more
information see sportys.com.
DATES: 2014: July 28-Aug. 3;
2015: July 27-Aug. 2