THIS COLUMN OFFERS a club reference, updates information about chokes, shares some 12-volt bench-supply info, and continues the "beginners' topics" section. Charles Varvaro, Box 694, Norco CA 92860, wrote to tell me of his club, the La Sierra Slope Soarers. Although the name does not suggest this. Electrics are part of the normal club activity. Charles invites you to visit the club Web site at www.lsss.homestead.com for varied info including a flying-site map. You are invited to visit the club's field in Riverside CA, where AMA members can fly as guests; see the Web site for details. And do tell 'em Bob sent ya! Chokes are electronic components. They are made with a wide variety of physical and electrical properties, but nearly all chokes are coils of wire in some form. The basic electrical unit of measure that describes the "value" or inductance of the choke is henrys—just as ohms describes the basic value of resistors. A fundamental property of chokes is their ability to impede the flow of AC signals, and this is what makes them of interest to the Electric flier. "RC Electrics" has discussed this topic several times through the years, and one good reference is the April 1995 column. You may want to look at your copy or get a reprint from AMA Headquarters. Here's why. In the earlier days of Electric, and especially several years ago with the advent of microprocessor-controlled Electronic Speed Controls (ESCs), power-system noise interfering with the airborne radio was quite common. Although this (and many other aspects of Electric flight) has improved greatly in time, there are still occasions when this old culprit shows up. This problem can take the form of apparent "range reduction"—often with the motor running and most often at "midthrottle" settings. Power-system electrical noise can travel along the ESC-to-receiver cable, get into the receiver, then interfere with the reception of the desired signal; i.e., the one from the transmitter. Common signs of this would be servo (surface) jitter and/or erratic motor speed, and sometimes even loss of control .This could occur during range check and/or in flight. These indicators would normally manifest with increasing distance from the transmitter. There are other ways for interfering noise to get into the receiver, This is a single choke and two "choke insertion units." Many power-system noise problems yield to chokes in the Electronic Speed Control-to-receiver cable. Representative power-system cells, packs, batteries. Shown are 100-2000 mAh capacities. but it seems that the ESC-to-receiver cable was and often is the dominant pathway to trouble. Fortunately, this particular problem is relatively easy to fix, and chokes are the solution. 1 normally keep several "choke insertion units" with my field supplies, to help others on the flightline with this common problem. As mentioned, it is the nature of chokes to impede the flow of AC signals, and that includes the kinds of noise that can cause us trouble. At the same time, properly selected chokes have little to no effect on the normal DC and control pulses that travel the ESC-to-receiver cable. Chokes "choke off much of the noise on this cable while remaining transparent to the normal cable purpose. Putting it yet another way, properly selected chokes appear as a high resistance to noise but a low resistance to the normal ESC-to-receiver interface. And yes, this includes BEC and non-BEC operation. I normally use small 10 microhenry (uH) molded chokes that look slightly like resistors but aren't. (A microhenry is one-millionth of a henry.) In years past I purchased them from ACE R/C, and more recently from RadioShack.com: the commercial (online) division of the familiar RadioShack® company. Since both of those suppliers have ceased parts operations. I have a new source for the same (and many other) parts: Mouser Electronics, which is an excellent company with which to do business. There is no "minimum order" and no small-order surcharge. The company can be reached at (800) 346-6873 or www.mouser.com. You can request a catalog and/or view the catalog online. The chokes I use are J.W. Miller Co. 77F series. The Mouser stock (catalog) number is 542-77F100, and they cost approximately $0.55 each. You need three for each installation: one for each of the three wires that make up a typical ESC-to-receiver interconnection. I strongly suggest that you check out the referenced column which describes in considerable detail the assembly and use of a "choke insertion unit." Basically, it is made from a shortened aileron extension cable selected to match your radio connectors. It is cut then reconnected with one choke in each of the three wires. This assembly can be inserted (plugged in series with) in the ESC-toreceiver cable. It can just as easily be removed. (I prefer not to cut and install the chokes in the actual ESC cable.) If you are having the kind of interference discussed in the preceding, the chances are very good that this approach will cure the problem. The chokes work almost every time. But as I said, the ESC-to-receiver cable is not the only possible path of trouble, so there is some possibility that the chokes are not a cure for a given problematic installation. Of course, if this "easy fix" doesn't solve your particular problem, you know you've got to look at other things —a win-win situation. One example of this was fully described in the April 2001 column, and I suggest that you add this second reference to your current attention. Because it is easy and cheap, make a "choke insertion unit" just to have on hand, even though you may not have any noise problems now. It is a useful tool to have "just in case." Also, you could do someone else on your flightline a big favor by having one handy to try. You could look like a genius and become a flightline hero at the same time! Of course, it's best to do before/after (without/with chokes) range checks while running the motor over the power range, and do verify that everything else in the airplane works properly before launch. A 12-volt bench supply is handy for powering chargers in the shop. Unfortunately, power supplies of sufficient capability can be quite costly. Some readers have referenced the use of salvaged computer switching power supplies for this purpose, as discussed in the May 2000 column. Another reference on this subject is QST, which is a monthly amateur radio magazine. The May 2002 issue contains an article entitled "The St. Louis Switcher." It describes in detail the acquisition, modification, and application of salvaged computer power supplies to provide a power source up to 100 watts for amateur-radio transceivers. And if it works for transceivers, it should certainly work for powering chargers! Many readers of this column will likely find the QST article of great interest and utility. The four-page discussion includes several color photos which can be a great aid with the several colored wires involved. If you can't get QST at your local library or from a Ham friend, you can get an article reprint (in black-and-white) from the American Radio Relay League (ARRL)—an organization like AMA. Call (860) 594-0278 and request a reprint. The cost is a flat $5 for nonmembers ($3 for ARRL members), and you can use your credit card for speedy service. Don't forget to reference that May 2000 MA column lor basic power considerations applicable to any 12-volt bench supply. The July column commenced a "beginner section" aimed at the most basic Electric-flight topics —those simple things that can baffle newcomers. I know what sorts of things can do this: they regularly appear in my incoming mail! Gus danger's (Philadelphia PA) scratch-built Winglet spans 78 inches, weighs 56 ounces, has geared Astro 05. Flies with gusto! The last two columns discussed basic battery stuff. This included info about cells, packs and batteries, charging considerations, and general "dos" and "don'ts." Recall that a cell is the smallest unit, or building block, and an interconnected (usually series-connected) set of cells is a battery. Often, the word "pack" is used to describe a popular number of cells, such as "a seven-cell pack," and such a pack can be the entire system battery. Think of "battery" as the overall descriptive term for the total collection of cells in a given installation —be they individual cells wired together, cells in a pack, or multiple interconnected packs. Sometimes "pack" and "battery" are used interchangeably, such as when one pack is the (total) battery. It's all in the jargon; it's not really difficult, but it can be confusing to someone who has never heard any of it. There is a bewildering array of battery product available to the Electric flier— something that was not so when I first flew E-power in the early 1970s. One photo shows just a few of today's myriad cell and battery styles and products. Included is a representative range, from a single 100 mAh cell to a custom-assembled 18-cell 2000 mAh pack. Also included are Ni-Cd and NiMH chemistries—a distinction not usually obvious by appearance. One common battery question concerns storage, and I have seen more than one opinion on this topic. I store motor packs in the discharged state. This means that I just "fly out" any charge as usual, so any flight could actually be the last flight of the day. The battery needs to be recharged to fly again. For me, this battery is "discharged." I could recharge and fly. or 1 can store the battery in this "discharged" condition. I've been using this approach forever. Now and then I may charge up then find that I'm unable to "fly it out." If there is a likelihood of going flying the next day, I'll "save it" overnight to fly the next day. Actually, I'd "top it off with the usual fast charger before the flight. This usually takes one or two minutes. If circumstances are such that I cannot go flying for more than a day or so, I'd likely put this battery on "slow" charge for an hour or more (depending on how many days elapsed) before going flying. This safely brings all cells up to full charge, as follows. The rationale is that cells in a battery can differ in their charge retention —more so with increasing storage time and/or temperature. This means they can become "unbalanced." Under these circumstances, it is usually advisable not to fast charge or discharge (fly) it. Rather, use a slow charge as in the preceding to bring all the cells up equal —a good starting point for a flight. Many readers inquire about a "first flight" experience not being "as good" as subsequent flights of that same outing. This is a common experience, and in general, you should expect this to be the case for most batteries. Similarly, it is common for a slow-charged pack to fuel a less-spirited flight than a fast-charged pack. These behaviors are not likely signs of impaired batteries or chargers. So concludes this beginning column of my 20th Model Aviation year. Please include an SASE with any correspondence for which you'd like a reply. Everyone so doing does get a reply! MA
Edition: Model Aviation - 2002/09
Page Numbers: 115, 116, 120
Edition: Model Aviation - 2002/09
Page Numbers: 115, 116, 120
THIS COLUMN OFFERS a club reference, updates information about chokes, shares some 12-volt bench-supply info, and continues the "beginners' topics" section. Charles Varvaro, Box 694, Norco CA 92860, wrote to tell me of his club, the La Sierra Slope Soarers. Although the name does not suggest this. Electrics are part of the normal club activity. Charles invites you to visit the club Web site at www.lsss.homestead.com for varied info including a flying-site map. You are invited to visit the club's field in Riverside CA, where AMA members can fly as guests; see the Web site for details. And do tell 'em Bob sent ya! Chokes are electronic components. They are made with a wide variety of physical and electrical properties, but nearly all chokes are coils of wire in some form. The basic electrical unit of measure that describes the "value" or inductance of the choke is henrys—just as ohms describes the basic value of resistors. A fundamental property of chokes is their ability to impede the flow of AC signals, and this is what makes them of interest to the Electric flier. "RC Electrics" has discussed this topic several times through the years, and one good reference is the April 1995 column. You may want to look at your copy or get a reprint from AMA Headquarters. Here's why. In the earlier days of Electric, and especially several years ago with the advent of microprocessor-controlled Electronic Speed Controls (ESCs), power-system noise interfering with the airborne radio was quite common. Although this (and many other aspects of Electric flight) has improved greatly in time, there are still occasions when this old culprit shows up. This problem can take the form of apparent "range reduction"—often with the motor running and most often at "midthrottle" settings. Power-system electrical noise can travel along the ESC-to-receiver cable, get into the receiver, then interfere with the reception of the desired signal; i.e., the one from the transmitter. Common signs of this would be servo (surface) jitter and/or erratic motor speed, and sometimes even loss of control .This could occur during range check and/or in flight. These indicators would normally manifest with increasing distance from the transmitter. There are other ways for interfering noise to get into the receiver, This is a single choke and two "choke insertion units." Many power-system noise problems yield to chokes in the Electronic Speed Control-to-receiver cable. Representative power-system cells, packs, batteries. Shown are 100-2000 mAh capacities. but it seems that the ESC-to-receiver cable was and often is the dominant pathway to trouble. Fortunately, this particular problem is relatively easy to fix, and chokes are the solution. 1 normally keep several "choke insertion units" with my field supplies, to help others on the flightline with this common problem. As mentioned, it is the nature of chokes to impede the flow of AC signals, and that includes the kinds of noise that can cause us trouble. At the same time, properly selected chokes have little to no effect on the normal DC and control pulses that travel the ESC-to-receiver cable. Chokes "choke off much of the noise on this cable while remaining transparent to the normal cable purpose. Putting it yet another way, properly selected chokes appear as a high resistance to noise but a low resistance to the normal ESC-to-receiver interface. And yes, this includes BEC and non-BEC operation. I normally use small 10 microhenry (uH) molded chokes that look slightly like resistors but aren't. (A microhenry is one-millionth of a henry.) In years past I purchased them from ACE R/C, and more recently from RadioShack.com: the commercial (online) division of the familiar RadioShack® company. Since both of those suppliers have ceased parts operations. I have a new source for the same (and many other) parts: Mouser Electronics, which is an excellent company with which to do business. There is no "minimum order" and no small-order surcharge. The company can be reached at (800) 346-6873 or www.mouser.com. You can request a catalog and/or view the catalog online. The chokes I use are J.W. Miller Co. 77F series. The Mouser stock (catalog) number is 542-77F100, and they cost approximately $0.55 each. You need three for each installation: one for each of the three wires that make up a typical ESC-to-receiver interconnection. I strongly suggest that you check out the referenced column which describes in considerable detail the assembly and use of a "choke insertion unit." Basically, it is made from a shortened aileron extension cable selected to match your radio connectors. It is cut then reconnected with one choke in each of the three wires. This assembly can be inserted (plugged in series with) in the ESC-toreceiver cable. It can just as easily be removed. (I prefer not to cut and install the chokes in the actual ESC cable.) If you are having the kind of interference discussed in the preceding, the chances are very good that this approach will cure the problem. The chokes work almost every time. But as I said, the ESC-to-receiver cable is not the only possible path of trouble, so there is some possibility that the chokes are not a cure for a given problematic installation. Of course, if this "easy fix" doesn't solve your particular problem, you know you've got to look at other things —a win-win situation. One example of this was fully described in the April 2001 column, and I suggest that you add this second reference to your current attention. Because it is easy and cheap, make a "choke insertion unit" just to have on hand, even though you may not have any noise problems now. It is a useful tool to have "just in case." Also, you could do someone else on your flightline a big favor by having one handy to try. You could look like a genius and become a flightline hero at the same time! Of course, it's best to do before/after (without/with chokes) range checks while running the motor over the power range, and do verify that everything else in the airplane works properly before launch. A 12-volt bench supply is handy for powering chargers in the shop. Unfortunately, power supplies of sufficient capability can be quite costly. Some readers have referenced the use of salvaged computer switching power supplies for this purpose, as discussed in the May 2000 column. Another reference on this subject is QST, which is a monthly amateur radio magazine. The May 2002 issue contains an article entitled "The St. Louis Switcher." It describes in detail the acquisition, modification, and application of salvaged computer power supplies to provide a power source up to 100 watts for amateur-radio transceivers. And if it works for transceivers, it should certainly work for powering chargers! Many readers of this column will likely find the QST article of great interest and utility. The four-page discussion includes several color photos which can be a great aid with the several colored wires involved. If you can't get QST at your local library or from a Ham friend, you can get an article reprint (in black-and-white) from the American Radio Relay League (ARRL)—an organization like AMA. Call (860) 594-0278 and request a reprint. The cost is a flat $5 for nonmembers ($3 for ARRL members), and you can use your credit card for speedy service. Don't forget to reference that May 2000 MA column lor basic power considerations applicable to any 12-volt bench supply. The July column commenced a "beginner section" aimed at the most basic Electric-flight topics —those simple things that can baffle newcomers. I know what sorts of things can do this: they regularly appear in my incoming mail! Gus danger's (Philadelphia PA) scratch-built Winglet spans 78 inches, weighs 56 ounces, has geared Astro 05. Flies with gusto! The last two columns discussed basic battery stuff. This included info about cells, packs and batteries, charging considerations, and general "dos" and "don'ts." Recall that a cell is the smallest unit, or building block, and an interconnected (usually series-connected) set of cells is a battery. Often, the word "pack" is used to describe a popular number of cells, such as "a seven-cell pack," and such a pack can be the entire system battery. Think of "battery" as the overall descriptive term for the total collection of cells in a given installation —be they individual cells wired together, cells in a pack, or multiple interconnected packs. Sometimes "pack" and "battery" are used interchangeably, such as when one pack is the (total) battery. It's all in the jargon; it's not really difficult, but it can be confusing to someone who has never heard any of it. There is a bewildering array of battery product available to the Electric flier— something that was not so when I first flew E-power in the early 1970s. One photo shows just a few of today's myriad cell and battery styles and products. Included is a representative range, from a single 100 mAh cell to a custom-assembled 18-cell 2000 mAh pack. Also included are Ni-Cd and NiMH chemistries—a distinction not usually obvious by appearance. One common battery question concerns storage, and I have seen more than one opinion on this topic. I store motor packs in the discharged state. This means that I just "fly out" any charge as usual, so any flight could actually be the last flight of the day. The battery needs to be recharged to fly again. For me, this battery is "discharged." I could recharge and fly. or 1 can store the battery in this "discharged" condition. I've been using this approach forever. Now and then I may charge up then find that I'm unable to "fly it out." If there is a likelihood of going flying the next day, I'll "save it" overnight to fly the next day. Actually, I'd "top it off with the usual fast charger before the flight. This usually takes one or two minutes. If circumstances are such that I cannot go flying for more than a day or so, I'd likely put this battery on "slow" charge for an hour or more (depending on how many days elapsed) before going flying. This safely brings all cells up to full charge, as follows. The rationale is that cells in a battery can differ in their charge retention —more so with increasing storage time and/or temperature. This means they can become "unbalanced." Under these circumstances, it is usually advisable not to fast charge or discharge (fly) it. Rather, use a slow charge as in the preceding to bring all the cells up equal —a good starting point for a flight. Many readers inquire about a "first flight" experience not being "as good" as subsequent flights of that same outing. This is a common experience, and in general, you should expect this to be the case for most batteries. Similarly, it is common for a slow-charged pack to fuel a less-spirited flight than a fast-charged pack. These behaviors are not likely signs of impaired batteries or chargers. So concludes this beginning column of my 20th Model Aviation year. Please include an SASE with any correspondence for which you'd like a reply. Everyone so doing does get a reply! MA
Edition: Model Aviation - 2002/09
Page Numbers: 115, 116, 120
THIS COLUMN OFFERS a club reference, updates information about chokes, shares some 12-volt bench-supply info, and continues the "beginners' topics" section. Charles Varvaro, Box 694, Norco CA 92860, wrote to tell me of his club, the La Sierra Slope Soarers. Although the name does not suggest this. Electrics are part of the normal club activity. Charles invites you to visit the club Web site at www.lsss.homestead.com for varied info including a flying-site map. You are invited to visit the club's field in Riverside CA, where AMA members can fly as guests; see the Web site for details. And do tell 'em Bob sent ya! Chokes are electronic components. They are made with a wide variety of physical and electrical properties, but nearly all chokes are coils of wire in some form. The basic electrical unit of measure that describes the "value" or inductance of the choke is henrys—just as ohms describes the basic value of resistors. A fundamental property of chokes is their ability to impede the flow of AC signals, and this is what makes them of interest to the Electric flier. "RC Electrics" has discussed this topic several times through the years, and one good reference is the April 1995 column. You may want to look at your copy or get a reprint from AMA Headquarters. Here's why. In the earlier days of Electric, and especially several years ago with the advent of microprocessor-controlled Electronic Speed Controls (ESCs), power-system noise interfering with the airborne radio was quite common. Although this (and many other aspects of Electric flight) has improved greatly in time, there are still occasions when this old culprit shows up. This problem can take the form of apparent "range reduction"—often with the motor running and most often at "midthrottle" settings. Power-system electrical noise can travel along the ESC-to-receiver cable, get into the receiver, then interfere with the reception of the desired signal; i.e., the one from the transmitter. Common signs of this would be servo (surface) jitter and/or erratic motor speed, and sometimes even loss of control .This could occur during range check and/or in flight. These indicators would normally manifest with increasing distance from the transmitter. There are other ways for interfering noise to get into the receiver, This is a single choke and two "choke insertion units." Many power-system noise problems yield to chokes in the Electronic Speed Control-to-receiver cable. Representative power-system cells, packs, batteries. Shown are 100-2000 mAh capacities. but it seems that the ESC-to-receiver cable was and often is the dominant pathway to trouble. Fortunately, this particular problem is relatively easy to fix, and chokes are the solution. 1 normally keep several "choke insertion units" with my field supplies, to help others on the flightline with this common problem. As mentioned, it is the nature of chokes to impede the flow of AC signals, and that includes the kinds of noise that can cause us trouble. At the same time, properly selected chokes have little to no effect on the normal DC and control pulses that travel the ESC-to-receiver cable. Chokes "choke off much of the noise on this cable while remaining transparent to the normal cable purpose. Putting it yet another way, properly selected chokes appear as a high resistance to noise but a low resistance to the normal ESC-to-receiver interface. And yes, this includes BEC and non-BEC operation. I normally use small 10 microhenry (uH) molded chokes that look slightly like resistors but aren't. (A microhenry is one-millionth of a henry.) In years past I purchased them from ACE R/C, and more recently from RadioShack.com: the commercial (online) division of the familiar RadioShack® company. Since both of those suppliers have ceased parts operations. I have a new source for the same (and many other) parts: Mouser Electronics, which is an excellent company with which to do business. There is no "minimum order" and no small-order surcharge. The company can be reached at (800) 346-6873 or www.mouser.com. You can request a catalog and/or view the catalog online. The chokes I use are J.W. Miller Co. 77F series. The Mouser stock (catalog) number is 542-77F100, and they cost approximately $0.55 each. You need three for each installation: one for each of the three wires that make up a typical ESC-to-receiver interconnection. I strongly suggest that you check out the referenced column which describes in considerable detail the assembly and use of a "choke insertion unit." Basically, it is made from a shortened aileron extension cable selected to match your radio connectors. It is cut then reconnected with one choke in each of the three wires. This assembly can be inserted (plugged in series with) in the ESC-toreceiver cable. It can just as easily be removed. (I prefer not to cut and install the chokes in the actual ESC cable.) If you are having the kind of interference discussed in the preceding, the chances are very good that this approach will cure the problem. The chokes work almost every time. But as I said, the ESC-to-receiver cable is not the only possible path of trouble, so there is some possibility that the chokes are not a cure for a given problematic installation. Of course, if this "easy fix" doesn't solve your particular problem, you know you've got to look at other things —a win-win situation. One example of this was fully described in the April 2001 column, and I suggest that you add this second reference to your current attention. Because it is easy and cheap, make a "choke insertion unit" just to have on hand, even though you may not have any noise problems now. It is a useful tool to have "just in case." Also, you could do someone else on your flightline a big favor by having one handy to try. You could look like a genius and become a flightline hero at the same time! Of course, it's best to do before/after (without/with chokes) range checks while running the motor over the power range, and do verify that everything else in the airplane works properly before launch. A 12-volt bench supply is handy for powering chargers in the shop. Unfortunately, power supplies of sufficient capability can be quite costly. Some readers have referenced the use of salvaged computer switching power supplies for this purpose, as discussed in the May 2000 column. Another reference on this subject is QST, which is a monthly amateur radio magazine. The May 2002 issue contains an article entitled "The St. Louis Switcher." It describes in detail the acquisition, modification, and application of salvaged computer power supplies to provide a power source up to 100 watts for amateur-radio transceivers. And if it works for transceivers, it should certainly work for powering chargers! Many readers of this column will likely find the QST article of great interest and utility. The four-page discussion includes several color photos which can be a great aid with the several colored wires involved. If you can't get QST at your local library or from a Ham friend, you can get an article reprint (in black-and-white) from the American Radio Relay League (ARRL)—an organization like AMA. Call (860) 594-0278 and request a reprint. The cost is a flat $5 for nonmembers ($3 for ARRL members), and you can use your credit card for speedy service. Don't forget to reference that May 2000 MA column lor basic power considerations applicable to any 12-volt bench supply. The July column commenced a "beginner section" aimed at the most basic Electric-flight topics —those simple things that can baffle newcomers. I know what sorts of things can do this: they regularly appear in my incoming mail! Gus danger's (Philadelphia PA) scratch-built Winglet spans 78 inches, weighs 56 ounces, has geared Astro 05. Flies with gusto! The last two columns discussed basic battery stuff. This included info about cells, packs and batteries, charging considerations, and general "dos" and "don'ts." Recall that a cell is the smallest unit, or building block, and an interconnected (usually series-connected) set of cells is a battery. Often, the word "pack" is used to describe a popular number of cells, such as "a seven-cell pack," and such a pack can be the entire system battery. Think of "battery" as the overall descriptive term for the total collection of cells in a given installation —be they individual cells wired together, cells in a pack, or multiple interconnected packs. Sometimes "pack" and "battery" are used interchangeably, such as when one pack is the (total) battery. It's all in the jargon; it's not really difficult, but it can be confusing to someone who has never heard any of it. There is a bewildering array of battery product available to the Electric flier— something that was not so when I first flew E-power in the early 1970s. One photo shows just a few of today's myriad cell and battery styles and products. Included is a representative range, from a single 100 mAh cell to a custom-assembled 18-cell 2000 mAh pack. Also included are Ni-Cd and NiMH chemistries—a distinction not usually obvious by appearance. One common battery question concerns storage, and I have seen more than one opinion on this topic. I store motor packs in the discharged state. This means that I just "fly out" any charge as usual, so any flight could actually be the last flight of the day. The battery needs to be recharged to fly again. For me, this battery is "discharged." I could recharge and fly. or 1 can store the battery in this "discharged" condition. I've been using this approach forever. Now and then I may charge up then find that I'm unable to "fly it out." If there is a likelihood of going flying the next day, I'll "save it" overnight to fly the next day. Actually, I'd "top it off with the usual fast charger before the flight. This usually takes one or two minutes. If circumstances are such that I cannot go flying for more than a day or so, I'd likely put this battery on "slow" charge for an hour or more (depending on how many days elapsed) before going flying. This safely brings all cells up to full charge, as follows. The rationale is that cells in a battery can differ in their charge retention —more so with increasing storage time and/or temperature. This means they can become "unbalanced." Under these circumstances, it is usually advisable not to fast charge or discharge (fly) it. Rather, use a slow charge as in the preceding to bring all the cells up equal —a good starting point for a flight. Many readers inquire about a "first flight" experience not being "as good" as subsequent flights of that same outing. This is a common experience, and in general, you should expect this to be the case for most batteries. Similarly, it is common for a slow-charged pack to fuel a less-spirited flight than a fast-charged pack. These behaviors are not likely signs of impaired batteries or chargers. So concludes this beginning column of my 20th Model Aviation year. Please include an SASE with any correspondence for which you'd like a reply. Everyone so doing does get a reply! MA
