The Battery Clinic - 2011/03

94 MODEL AVIATION
A 1965 Proline transmitter with built-in
charging.
A small collection of early chargers.
A charger ahead of its time, the Victor
Engineering Super 2 IQ was completely
user-programmable and could handle
Lithium technologies long before they
came out.
Clockwork chargers/dischargers employed a timer that would disengage when the
voltage dropped to a preset point and give you a reading of how long the discharge
lasted.
I’M WRITING THIS because I got tired of
waiting for someone else to do it.
Early radio-control systems depended on
carbon-zinc batteries. Vacuum-tube receivers
and transmitters employed two: one for
filament voltage, usually 6 volts, and one for
the “B” high-voltage supply that vacuum tubes
required.
There were no rechargeable batteries
available, other than the lead-acid type. They
were sometimes used as ground-based
transmitter batteries in conjunction with a
voltage converter for the higher voltage.
The November-December 1957 Grid
Leaks magazine showed circuits for
converting a tube receiver to use transistors in
place of the temperamental relay. Then
transistorized audio sections and, shortly
thereafter, completely transistorized receivers
showed up. These worked at much lower
voltages than the tube versions, so
rechargeable packs became viable.
The November-December 1959 Grid
Leaks introduced the Eveready Ni-Cd AA
battery, while surplus button cell batteries
were emerging on the market. These were
known as “VO” cells and were sold
exclusively through ACE R/C.
Then circuits for making your own
charger came onto the market. They consisted
simply of a current-limiting resistor and
bridge rectifier connected directly to a 120-
volt AC outlet. These were not for the
careless modeler, because you were exposed
to the line voltage anytime you touched the
battery pack.
One of the first commercial chargers
(May 1960) specifically for the VO and
Eveready cell packs was from MC
Manufacturing & Sales. It provided a
potentiometer that controlled current up to
250 mA. You provided your own 0-500 mA
meter.
Radios then showed up with chargers built
in. You connected your receiver pack to the
transmitter and then plugged the transmitter
into an AC outlet. Proline employed such an
arrangement, which is shown.
Our charging needs were soon met by the
familiar wall-wart chargers with fixed output
for transmitter and receiver batteries. These
are still the most common way to charge our
system batteries.
Early chargers took many forms and were
designed to charge both your transmitter and
receiver packs at a fixed rate. Readouts were
blinking lights, such as on the Micropace, or
simply an indication of charge status, as on
the MEN.
There were specialized chargers for leadacid
field-box batteries as well, which were
either wall warts or those such as the ACE
CVC. For years ACE chargers fulfilled the
Red Scholefield | redscho@The Battery Clinic bellsouth.net
A half-century of chargers
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March 2011 95
Today’s popular four-button chargers seem to have the same
general programming. Shown is a sampling of what is available.
Computer-driven chargers have provisions for connection to your
computer, to monitor operation and track and store data.
Above: The Dymond Modelsport Super
Turbo Quad Charger and Hitec X4 bring
Li-Poly balancing to all four ports and offer
Ni-Cd, NiMH, and Pb charge/discharge and
cycle capability.
Left: Multiport chargers are quite popular,
thanks to their ability to significantly
reduce the time spent charging batteries.
need for charging up to 500 mAh rates.
The HD500 is good for 500 mA, while the
DMVC is 250 mA but can handle two packs
independently. If you can pick up one at a
swap meet, grab it. It is good for any Ni-Cd or
NiMH battery with up to roughly 14 cells.
The need to test packs by discharging was
addressed by the early clockwork units. They
employed a timer that would disengage when
the voltage dropped to a preset point and give
you a reading of how long the discharge
lasted.
The discharge rates were preset in the
Super Cycle, while you could set it in the
Leisure Electronics unit. I had cannibalized
this charger for parts, so I’m not sure how it
worked. A unit by LR Taylor was similar to
the Super Cycle, except that it was calibrated
in mAh rather than minutes.
A Charger Ahead of Its Time: The Victor
Engineering Super 2 IQ was popular with the
RC car set because of its motor-test capability.
However, because it was completely userprogrammable,
it could handle Lithium
technologies long before they came out. One
could set the charge algorithms from a touch
pad to suit whatever protocol was required.
I used the Super 2 IQ in my early work
with Lithium, before any others were
available. I removed the motor function and
had it reworked for more precise control of
the charge currents. It was called the
“Industrial” version, because a number of
battery-powered-device manufacturers used it
for battery selection and testing.
This charger set the bar for all units made
ever since. Unfortunately the manufacturer
closed shop to return to Europe, to manage the
family industrial estate.
Multiport Chargers: Of all the units we have
seen, none is more interesting than the Litco
Alpha 4. It had the unique ability to charge
and discharge four packs independently, but
more intriguing was how it was marketed.
When the Alpha 4 was introduced, you
could simply order one from the manufacturer/
supplier. Once he reached an order level at
which he was no longer comfortable, you had
to play what became known as the “Litco
Lottery.”
He would open the order window for a
few days, and you placed your order there. If
you were fast enough, you “won” the
privilege of paying a couple hundred dollars
for the charger—as long as you were not a
resident of Pennsylvania, where sales tax was
required. The owner refused to collect
sales taxes.
Eventually and without notice,
production of the Alpha 4 stopped, and it
is no longer available. Hughes RC
introduced an alternative in its Spectra 4. It
did basically the same thing as the Alpha
4, but also had Lithium-charge
capabilities.
Sirius makes a four-port charger (with
which I have had no experience), but it has
limited programming for Ni-Cd and NiMH
only. The ElectriFly PolyCharge 4
accommodates only Lithium batteries.
Dymond Modelsport has introduced its
Super Turbo Quad Charger, which brings
Li-Poly balancing to all four ports, as well
as offering Ni-Cd, NiMH, and Pb charge/
discharge and cycle capability. Dymond
also sells a compact 200-watt, 12-volt
switch-mode power supply for bench
operation.
Preliminary testing of the Super Turbo
Quad Charger shows that each channel
operates in a manner identical to on the
Super Turbo II, which I reviewed in the
September column. The price is $139 and
$55 for the power supply. Hitec also sells a
version of this charger.
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96 MODEL AVIATION
which could miscount the number of cells
if a fully charged pack were connected.
The FMA Direct Cellpro 4S was one of
the first balancing chargers with
capabilities extended to cover the new
LiFePO4 technology.
High-End Chargers: There is always a
quest for the ultimate charger—one that
will make everyone happy. Of course that
is impossible to attain.
The Tejera Microsystems Engineering
Xtrema is an example of design creativity.
Although it is limited to Lithium
technology, it is unique in that it includes a
watt meter function. There are numerous
accessories that can enhance the
capabilities of the Xtrema.
The Cellpro Power Lab 8 from FMA
Direct is touted to support all current and
future battery chemistries. The 1,344-watt
unit offers high-power charge and
discharge capabilities. It features a
computer interface as well, that enables the
aeromodeler to log and graph all major
operations when using the free chargecontrol
software.
I have only scratched the surface; literally
hundreds of chargers have been offered to
our hobby. Some have been excellent, such
as the Shultz and Orbit. To cover more
would require a large book and more time
than I would want to dedicate to such an
endeavor.
Spring is on its way. Make sure that you
have that winter project checked over well
before your first flight. It might be better
to limber up on something familiar. MA
Sources:
Sirius
(800) 532-0092
www.siriuselectronics.com
ElectriFly
(800) 637-7660
www.electrifly.com
Dymond Modelsport USA
(858) 220-4004
(786) 339-9998
www.rc-dymond.com
Hitec
(858) 748-6948
www.hitecrcd.com
Vencon
(416) 226-2628
www.vencon.com
FMA Direct
(800) 343-2934
www.fmadirect.com
AstroFlight
(949) 855-9903
www.astroflight.com
Tejera Microsystems Engineering
11705 Boyette Rd. #418
Riverview FL 33569
www.tmenet.com
Red Scholefield’s The Battery Clinic
12219 NW 9th Ln.
Newberry FL 32669
www.hangtimes.com/redsbatteryclinic.html
Four-button units seem to be the chargers
du jour. It seems like a new one, in this
now-familiar format, hits the market every
day.
All seem to have the same general
programming. Shown is a small sampling
of what is available. These are good
multichemistry chargers and serve most
modelers’ charging needs.
Computer-Based Chargers: Many units
sold today have provisions for connection
to your computer, to monitor operation, but
some can be operated only using a
computer. One of the better options is the
UBA5 by Vencon.
With its graphical programming
interface, you can easily design a battery
test to do exactly what you want. You can
specify the charge method (constant
current or constant voltage with peak,
timed, or temperature termination) and the
charge and discharge currents. You can
even use conditional loops in the test.
All voltage, current, and temperature
readings are stored in a standard text
results file. But the UBA5 is of limited
appeal to the aeromodeling community
because of its $875 price tag.
Multichemistry Chargers: Many modern
units address all battery chemistries that a
modeler encounters. One of the more
popular options is the ElectriFly Triton
series, and the latest—the 2EQ—offers
either AC or DC input and provides for
Lithium balancing.
The FMA Direct Cellpro Multi4 is
perhaps one of the easiest chargers to
program. Its computer interface with open
architecture lets you create an endless
number of charge-maintenance protocols.
Lithium Charger Progress: Lithium
batteries brought a new challenge to
charger manufacturers. These batteries’
needs were completely different from those
of Ni-Cd and NiMH.
The first units ignored the fact that
Lithium packs need to be balanced
occasionally and produced poor results and
sometimes hazardous situations. The life of
the unbalanced packs was severely
compromised at best, and fires were
attributed to their use in the worst case.
One of the earliest available Lithium
chargers was the Kokam from FMA Direct.
It was followed by the AstroFlight 109,
Lithium batteries brought a new challenge to charger
manufacturers, which stepped up to offer units that balanced
while they charged.
Multichemistry chargers handle all battery chemistries that a
modeler encounters.
The Xtrema and Power Lab 8 can be considered high-end, with the ability to charge huge
packs. The latter is capable of up to 40 amps and 1,344 watts!
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