help
#1
Thread Starter
Junior Member
Joined: Oct 2003
Posts: 16
Likes: 0
Received 0 Likes
on
0 Posts
From: chaffee,
MO
Hi I am 17 and i have a magic and crashed it and am going to buy a new one can you tell me a better place to put my receiver and pics if possible and my batt keep running down.
#5
Senior Member
Joey ... you have to do a lot of shifting about to get things in the Magic fuse, hope you are using a mini RX. Mine was your old standard one and it was hell! With a 4 cell pack you can easily do 4 flights on the Magic with standard servos. Are you running for more than 6 flights?
#7
Senior Member
Joey ... its time for a new battery. Also get NiMH batteries, they need not be cycled/conditioned. Get those they use for RC cars, about 1,100 mAh. They are much smaller. Get the 5 cell hump packs, a row of 3 and then another row of 2 above that.
#8

My Feedback: (12)
Joey, some questions and then some suggestions.
What is the capacity of the receiver battery pack? How old is it? What is its capacity? Is it a nicad or nimh? If it's a nicad, have you ever cycled it? Do you test the voltage before you fly? Are any of your linkages binding (which creates extra work for the servos)? Do any of the servos make noise while you hold the sticks still, or when you move one of them to the maximum throw?
And now the suggestions:
It's not normal to have a battery run down in 9 minutes. If this is happening then you've either got a bad battery, or a nicad that needs to be cycled, some kind of short in the wiring, or your linkages are binding, which causes the servos to work too hard.
If you don't have one already, buy a battery tester. You need this to make sure the battery is fully charged before you fly. Use it at the beginning of the flying session and then before every flight. The brand does not really matter, just be sure you get one that applies a load to simulate the receiver and a few servos. A normal volt meter from Radio Shack does not include a load. Here's an inexpensive example of an R/C battery tester: http://www.towerhobby.com/products/towp1181.html
If the receiver battery pack is NiCad, you should cycle it a couple times. NiMH packs don't develop memory, so they don't need to be cycled, but running them through a cycle is a good way to test the capacity, and to know when it's time to replace an old pack. To cycle the battery you will need to discharge it. There are several ways to do this. The least expensive way is to turn on the transmitter and receiver and move the controls until they get sluggish. I suspect you have better things to do with your time, and it's not very scientific, so I do not recommend this method. Another choice is to hook the receiver pack to your battery tester. Using the battery tester requires that you watch it to see when the voltage drops off. You don't have to stare at it for the duration, just check on it every 5 or 10 minutes. You don't want to let it drain the pack fully. Another way is to buy one of the many products available for automatically cycling batteries. These are nice because you don't need to watch to see when the battery is discharged, they will automatically cut off at a certain voltage. The more expensive ones include a digital display to report the results of the test. Many of them automatically charge the battery after the discharge is complete. I'd rather spend my money on stuff that flies, so I just use my battery tester.
For information on the details of NiCad memory and the need for cycling, do some searches. There are many threads out there that explain it, so I'll be brief. Charge the battery. Hook it to your discharge tool of choice and time how long it takes to go below the recommended safe flying low voltage. Charge it again and repeat the test. If the battery was in need of cycling, you will find the second test lasts much longer than the first. If the battery is running down quickly after recycling it a few times, get a new one. Note, don't throw the old one in the trash, recycle it.
Next check the linkages to your control surfaces. You want all of these to move easily by hand. If they do not move easily then your servo needs to do extra work. This makes them use more power, and they also move slower. Also test to see if the servo moves to a point where the control cannot move any more. This will stall the servo and use a large amount of power. To test for this, move each control to the max in each direction. If you hear the servo humming, it may be stalling. If your transmitter has end point adjustments (EPA), use them. If you don't have EPA, you will have to adjust the linkages. Once you've confirmed that the linkages are working right, see how long the battery lasts while you are moving the controls around at home.
If you need to replace your battery, as tIANci said, consider buying a NiMH battery. They do not need to be cycled, and are smaller (and lighter). Since they are smaller for a given capacity, you can get a higher capacity pack (longer flying time) for the same size/weight. For example, the standard NiCad packs are 600-700 mAh. The same size/weight NiMH pack would be 1100-1250 mAh. The suggested 5 cell pack is not a requirement. The advantage of 5 cells is the servos will have more torque and will move faster. For the typical sport flier, the extra speed does not matter. If you're doing 3D or other competition, the extra speed helps. The disadvantages are the extra cell makes the pack a bit heavier/larger, and the pack will run down a little faster. The discharge rate of 4 cell versus 5 cell packs has been the subject of much debate, hopefully another one will not start here. If anyone is interested, look for some of the threads that have beat the subject to death.
There are many online sources of batteries. Here are a couple:
http://batteriesamerica.com/
http://www.hangtimes.com/nobsbatteries.html
I don't think there is any reason to look for a car pack. It's easy to find receiver packs with the appropriate connector already installed. Sanyo cells tend to be highly rated.
What is the capacity of the receiver battery pack? How old is it? What is its capacity? Is it a nicad or nimh? If it's a nicad, have you ever cycled it? Do you test the voltage before you fly? Are any of your linkages binding (which creates extra work for the servos)? Do any of the servos make noise while you hold the sticks still, or when you move one of them to the maximum throw?
And now the suggestions:
It's not normal to have a battery run down in 9 minutes. If this is happening then you've either got a bad battery, or a nicad that needs to be cycled, some kind of short in the wiring, or your linkages are binding, which causes the servos to work too hard.
If you don't have one already, buy a battery tester. You need this to make sure the battery is fully charged before you fly. Use it at the beginning of the flying session and then before every flight. The brand does not really matter, just be sure you get one that applies a load to simulate the receiver and a few servos. A normal volt meter from Radio Shack does not include a load. Here's an inexpensive example of an R/C battery tester: http://www.towerhobby.com/products/towp1181.html
If the receiver battery pack is NiCad, you should cycle it a couple times. NiMH packs don't develop memory, so they don't need to be cycled, but running them through a cycle is a good way to test the capacity, and to know when it's time to replace an old pack. To cycle the battery you will need to discharge it. There are several ways to do this. The least expensive way is to turn on the transmitter and receiver and move the controls until they get sluggish. I suspect you have better things to do with your time, and it's not very scientific, so I do not recommend this method. Another choice is to hook the receiver pack to your battery tester. Using the battery tester requires that you watch it to see when the voltage drops off. You don't have to stare at it for the duration, just check on it every 5 or 10 minutes. You don't want to let it drain the pack fully. Another way is to buy one of the many products available for automatically cycling batteries. These are nice because you don't need to watch to see when the battery is discharged, they will automatically cut off at a certain voltage. The more expensive ones include a digital display to report the results of the test. Many of them automatically charge the battery after the discharge is complete. I'd rather spend my money on stuff that flies, so I just use my battery tester.
For information on the details of NiCad memory and the need for cycling, do some searches. There are many threads out there that explain it, so I'll be brief. Charge the battery. Hook it to your discharge tool of choice and time how long it takes to go below the recommended safe flying low voltage. Charge it again and repeat the test. If the battery was in need of cycling, you will find the second test lasts much longer than the first. If the battery is running down quickly after recycling it a few times, get a new one. Note, don't throw the old one in the trash, recycle it.
Next check the linkages to your control surfaces. You want all of these to move easily by hand. If they do not move easily then your servo needs to do extra work. This makes them use more power, and they also move slower. Also test to see if the servo moves to a point where the control cannot move any more. This will stall the servo and use a large amount of power. To test for this, move each control to the max in each direction. If you hear the servo humming, it may be stalling. If your transmitter has end point adjustments (EPA), use them. If you don't have EPA, you will have to adjust the linkages. Once you've confirmed that the linkages are working right, see how long the battery lasts while you are moving the controls around at home.
If you need to replace your battery, as tIANci said, consider buying a NiMH battery. They do not need to be cycled, and are smaller (and lighter). Since they are smaller for a given capacity, you can get a higher capacity pack (longer flying time) for the same size/weight. For example, the standard NiCad packs are 600-700 mAh. The same size/weight NiMH pack would be 1100-1250 mAh. The suggested 5 cell pack is not a requirement. The advantage of 5 cells is the servos will have more torque and will move faster. For the typical sport flier, the extra speed does not matter. If you're doing 3D or other competition, the extra speed helps. The disadvantages are the extra cell makes the pack a bit heavier/larger, and the pack will run down a little faster. The discharge rate of 4 cell versus 5 cell packs has been the subject of much debate, hopefully another one will not start here. If anyone is interested, look for some of the threads that have beat the subject to death.
There are many online sources of batteries. Here are a couple:
http://batteriesamerica.com/
http://www.hangtimes.com/nobsbatteries.html
I don't think there is any reason to look for a car pack. It's easy to find receiver packs with the appropriate connector already installed. Sanyo cells tend to be highly rated.
#10
Senior Member
My Feedback: (1)
Joined: Mar 2003
Posts: 1,774
Likes: 0
Received 0 Likes
on
0 Posts
From: Canyon Country, CA
Something is very wrong. Are the servos you are using up to the task? I had to replace my rudder and elevator servos in my Magic for servos with higher torque. The standard Hitec 311's I was using just couldnt do it.
I am using a standard 600mAh rx pack (nicad) and I can fly all morning if I wish before needing to recharge. I have it mounted up on end against the back of the front compartment bulkhead, right behind the fuel tank. The receiver is just a bit behind that up on end also. I am using a Berg 6 rx with the plugs in the end. Makes it easy to plug in the aileron leads.
I had to bend a bit of an angle into the ends of the rudder push rods to make em operate smoothly without binding and at full throw. I keep meaning to replace em all together and go for a pull pull cable setup.
If you are cycling that battery properly and it goes dead in 9 minutes, I would replace it.
Check those servos. Upgrade if needed.
Check for binding. Fix if needed.
Since you are building a replacement, be extremely patient and careful when cutting the pushrods to length. If they are too short or too long, you will be working the servos to death. You want em just tight enough that there is no slop but not to where they are pulling on the servo arms.
I am using a standard 600mAh rx pack (nicad) and I can fly all morning if I wish before needing to recharge. I have it mounted up on end against the back of the front compartment bulkhead, right behind the fuel tank. The receiver is just a bit behind that up on end also. I am using a Berg 6 rx with the plugs in the end. Makes it easy to plug in the aileron leads.
I had to bend a bit of an angle into the ends of the rudder push rods to make em operate smoothly without binding and at full throw. I keep meaning to replace em all together and go for a pull pull cable setup.
If you are cycling that battery properly and it goes dead in 9 minutes, I would replace it.
Check those servos. Upgrade if needed.
Check for binding. Fix if needed.
Since you are building a replacement, be extremely patient and careful when cutting the pushrods to length. If they are too short or too long, you will be working the servos to death. You want em just tight enough that there is no slop but not to where they are pulling on the servo arms.
ORIGINAL: joeykang
I bought the batt in Feb 2004 it was cycled 3 times it is nicad.
I bought the batt in Feb 2004 it was cycled 3 times it is nicad.




