Frequently Asked Questions - 2006/08

How to find hobby shops in your area
? Frequently Asked Questions Bob Aberle | [email protected]
Also included in this column:
• Synthesized RC modules
• Voltmeters and shunts
• Klass Kote epoxy paints
• Tracker III channel mapping
• Twelve-volt power supplies
• Wendell Hostetler’s Aeronca
Champ
The author used the Ask.com search engine to obtain a list of local hobby shops.
FMA Direct is offering this digital multimeter with a shunt (to the left) that extends
the current-measuring capability.
New JR synthesized dual-conversion
receiver (part JRPR2000) automatically
locks onto your transmitter’s frequency.
THIS IS THE 29th monthly column in
which I try to give you the best possible
answers to questions you have written or
E-mailed to me. Each new question is
given a sequential number for
identification purposes.
Until now this column has appeared in
the pages of MA and additional questions
and answers have been posted on a special
section of the AMA Web site
(www.modelaircraft.org). That Web page
is now in the process of being revised and,
as such, there will be no new postings in
the foreseeable future.
What you read each month in print is
all you will see. I will advise you when
we are able to return to the original
format. The original “search process” by
categories will also be suspended until the
posting is back online.
In the meantime, I’m available to help
you locate specific subjects of interest.
Just drop me an E-mail. Also please keep
sending in your questions; that’s the only
way I can continue to provide this service
to readers.
Q238: “I recently tried the Hobby Shop
Locator function on the AMA Web site
92 MODEL AVIATION
08sig3.QXD 6/23/06 12:02 PM Page 92August 2006 93
and found it somewhat confusing to use. Can you suggest
another way to do this?”
A238: The AMA Web site has an excellent “Charter Club
Locator” function. You enter your zip code and it will supply
the names and phone numbers of local club representatives.
That locator works quite well. Unfortunately the Hobby Shop
Locator function is, as you pointed out, not that easy to use.
To find something more helpful I tried several Internet
search engines to see what was available. I had just heard
mention of a new search engine at www.ask.com and tried it.
Quickly I came up with the address http://local.ask.com/
local?terms=Hobby+Shop. All you have to do is enter your
hometown or city and state. That immediately gets you a list of
all the hobby shops in your area. You get more than just the
model-aircraft hobby, but it is easy to sort out the ones in which
you might be interested.
I had several friends across the country
try this locator, and they all indicated that
they learned about new hobby shops they
never knew existed. Please give this
hobby-shop locator a try and let me know
how you make out.
Q239: “In Q228 you mentioned a new JR
synthesized RF module intended for
certain JR RC transmitters that allows you
to dial up any one of the 50 RC aircraft
channels (one rotary dial for each digit).
If I were to purchase this module, how
would I go about changing the channel on
the receiver end? Would I need a different
crystal for each channel?”
A239: When synthesized RC transmitter
modules came onto the market years ago,
some required that you change the crystal
each time at the receiver end. That meant
you had to access the receiver, located in
the fuselage, and then physically change
the crystal.
As time went on, some manufacturers
came out with synthesized receivers, with
the same two rotary dials as they had on
the transmitter module. Again, you had to
Klass Kote protects decals from hot fuels. Clear epoxy Part-A is
flanked by Part-B catalysts for gloss and satin finishes.
FMA Direct is currently supplying this 12VDC power supply
capable of up to 10 amps output for just $49.95.
Polk’s Tracker III synthesized transmitter had its software
upgraded to include “channel mapping,” explained in text.
Wendell Hostetler with his new 1/4-scale Aeronca 7AC Champion. He is offering fullsize
plans for this model, which can be powered by electric, gas, or glow.
08sig3.QXD 6/23/06 11:39 AM Page 93access the receiver, within the fuselage, to
change the channel dials. More recently
we have seen several synthesized RC
receivers that simply lock on or set
themselves to the adjacent RC
transmitter’s operating channel.
Right after I wrote about the new JR
synthesized transmitter module I learned
that JR had also just introduced a new 10-
channel synthesized dual-conversion
receiver. It is designated model
JRPR2000 and is available, as are all JR
RC products, from Horizon Hobby.
I don’t know the details yet, but this
new receiver does lock onto the
transmitter frequency without the need to
access it or rotate any dials.
Q240: “I keep hearing you and other
electric power enthusiasts always talking
about measuring motor current. I already
own a reasonably accurate digital
volt/ammeter. Why must I go out and buy
one of those $60 to $80 dedicated
meters?”
A240: Buying an AstroFlight Super
Whattmeter or the Medusa Power
Analyzer gets you a meter that provides
voltage, current, and power (watts)
measurements directly. Before these
dedicated meters were available, most of
us used a simple voltmeter with a shunt
resistor.
Measuring the voltage drop across
that shunt provided an equivalent current
(amps) readout on your voltmeter. The
trick in using this shunt was to select the
right value so the equivalent voltage
produced convenient current
measurements.
If you already own a digital voltmeter
or multimeter, all you need is that shunt
and you can measure relatively large
amounts of current—certainly much
more than you could measure on the
multimeter’s regular current scales.
As a convenience to our electricpower
hobbyists, FMA Direct is selling
the DVM-Shunt-60 meter shunt for only
$14.95. It will allow you to measure
currents up to 60 amps continuous and
100 amps (short duration up to one
minute).
If you don’t have a digital
multimeter, FMA Direct can sell you one
along with the meter shunt for just
$44.95. That meter will give you much
more utility value than a dedicated
hobby meter. Go to www.fmadirect.com/
detail.htm?item=2111&section=57 for
more information.
Q241: “I noticed in your Q/A169,
concerning decals, that a can of Krylon
#1303 clear acrylic spray paint was
pictured. This spray was recommended
to protect the homemade decals from
exposure to hot fuels. After some
investigation I learned that the #1303
clear spray is fuelproof, while a
comparable product #1301 is not hot
fuelproof.
“It is also my understanding that this
protective spray will tend to eventually
‘yellow’ when exposed to UV light
(sunlight). Is there any comparable
product that can be used that doesn’t
have this property?”
A241: I felt that this question deserved a
thorough answer and resorted to
consulting with my friend and expert
modeler Scott Christensen of Sig
Manufacturing Co.
He indicated that he has had excellent
results using a two-part clear epoxy
paint to protect his decals. Our old
favorites, Hobbypoxy and K&B Super
Poxy, are no longer on the market, but
Scott pointed out that a new product
called Klass Kote is available. The Web
site is www.klasskote.com.
When I called up this Web page I wassurprised to learn that Klass Kote offers a
complete line of two-part epoxy paints in
a wide variety of colors and can sizes.
Scott mentioned that he sprays the clear
epoxy over the decals using an airbrush.
The yellowing effect will also occur
with the epoxy, but it takes much longer
for that to happen. Also, the yellowing is
most noticeable when white is the
background color; it isn’t really a
problem for other colors.
So now you have an interesting line of
hobby paints to look at!
Q242: “I understand that the Polk’s
Tracker III synthesized transmitter that
you reviewed recently in Model Aviation
will soon have revised software that will
enable ‘channel mapping.’ Is this
something important?”
A242: I must admit that I wasn’t familiar
with the term “channel mapping” when I
first read this question. It involves the
order in which the channel functions line
up on your RC receivers. JR and
Airtronics receivers have one order, and
Futaba, Hitec, Cirrus, Robbe, and
Multiplex have a different order.
The first connector on a JR receiver
might be for the throttle function, while
that is the aileron function on a Futaba
receiver. You can easily get around this
by swapping your servo cables at the
receiver connector block.
But to make life easier Polk’s
engineers have modified the Tracker III
transmitter software to provide for a
choice of “Channel Mapping” in the
“Track 1” menu. This feature was
included in the first software upgrade
that was released toward the end of
January (2006).
Q243: “In Q103 you mentioned several
sources for 12-volt power supplies that
would allow you to operate a 12-volt DC
charger from a 115VAC power source.
The two that you recommended were
quite large in size and expensive. Is
there anything smaller available?”
A243: There probably are many smaller
alternatives. In a quick check I noticed a
new 10-amp-capable 12VDC power
supply being offered by FMA Direct.
You can find it at www.fma
direct.com/detail.htm?item=1994&sectio
n=. The current price is $49.95.
Indoor RC electric modelers are
finding this a handy power supply when
operating their battery chargers inside
gymnasiums and sports arenas, where
they can’t access their car batteries.
Q244: “I know the Aeronca 7AC
Champion has been one of your favorite
aircraft. You had mentioned that you
always wanted to try a 1/4-scale electric
version. Is there a particular kit or plans
that you might have in mind?”
A244: I suspect there are several kits and
plans available for the famous Aeronca
Champ. My good friend Wendell
Hostetler has been promising me a set of
plans for his new 1/4-scale version.
A few weeks ago came a photo of his
completed prototype. It is actually 26%
of the original size with a 109-inch
wingspan and 1,622 square inches of
wing area. The weight range, depending
on your power system, is 12-15 pounds.
Wendell claims that it can be powered by
electric, glow, or gas without structural
modifications.
His Web site is www.aerosports.
com/whplans/. These plans will
sell for $43.50 plus $6 postage. A photo
is included with this column.
That’s a wrap for this month! Your
thoughts about the current Web site
situation are welcomed! MA