Frequently Asked Questions - 2006/08
Bob Aberle | [email protected]
How to find hobby shops in your area
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 Model Aviation 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 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 first came onto the market, some required that you change the crystal at the receiver end. That meant accessing the receiver, located in the fuselage, and physically changing the crystal. As time went on, some manufacturers came out with synthesized receivers, with the same two rotary dials as on the transmitter module. Again, you had to access 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 all the technical 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 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 electric-power 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. See www.fmadirect.com/detail.htm?item=2111§ion=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 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 consulted 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. 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.
For example, the first connector on a JR receiver might be for the throttle function, while that same position on a Futaba receiver might be aileron. You can easily get around this by swapping your servo cables at the receiver connector block.
To make life easier, Polk's engineers modified the Tracker III transmitter software to provide 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 12V DC power supply being offered by FMA Direct. You can find it at www.fmadirect.com/detail.htm?item=1994§ion=. 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 I received 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.aero-sports.com/whplans/. These plans will sell for $43.50 plus $6 postage. A photo is included with the plans.
That's a wrap for this month! Your thoughts about the current Web site situation are welcomed! Model Aviation
Transcribed from original scans by AI. Minor OCR errors may remain.
