What causes a brownout?
03-12-2012 | 06:15 PM
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From: , MD
RE: What causes a brownout?
ORIGINAL: Rockin Robbins
I don't know whether your plane is electric or internal combustion. It IS important to the question, you know. I come from the electric side of things. There brownouts are always not far from our thoughts, no matter what kind of radio we use. The battery elimination circuits in our electronic speed controls often are not robust enough to provide the amount of power our radios and servos will draw. If your radio and servos at peak draw, with four servos drawing power at the same time needs more amperage than your battery elimination circuit can provide, you get a voltage drop, no matter what condition your batteries are in. It also doesn't matter what kind of radio you have, you can brown them all out.
I don't know whether your plane is electric or internal combustion. It IS important to the question, you know. I come from the electric side of things. There brownouts are always not far from our thoughts, no matter what kind of radio we use. The battery elimination circuits in our electronic speed controls often are not robust enough to provide the amount of power our radios and servos will draw. If your radio and servos at peak draw, with four servos drawing power at the same time needs more amperage than your battery elimination circuit can provide, you get a voltage drop, no matter what condition your batteries are in. It also doesn't matter what kind of radio you have, you can brown them all out.
All you have to do is draw more amperage than your battery or battery elimination circuit can produce and your voltage will drop. When it does, there's a point where your radio quits working.
Have you considered the possibility that you didn't brown out at all, but were masked by some object opaque to radio waves, like a power line, possibly a fence, or even the earth itself? I've been shot down going behind a hill with 2.4 Ghz equipment. It is strictly line of sight and LOTS of things can break that line. Again, the brand of radio doesn't matter there.
Have you considered the possibility that you didn't brown out at all, but were masked by some object opaque to radio waves, like a power line, possibly a fence, or even the earth itself? I've been shot down going behind a hill with 2.4 Ghz equipment. It is strictly line of sight and LOTS of things can break that line. Again, the brand of radio doesn't matter there.
03-12-2012 | 06:40 PM
#29
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RE: What causes a brownout?
ORIGINAL: zacharyR
FYI LOAD TESTING IS SOON TO BE A THING OF THE PAST
FYI LOAD TESTING IS SOON TO BE A THING OF THE PAST
When JR finally decided they had a problem with there 2.4 system they told you on there web site how to check if you had one of the original RXs. They would take from 4 to 6 seconds {sometimes even longer} to boot back up after signal loss. You just turned on your radio and plane moved the controls into something like a turn or snap roll then turned off your radio, then you turned it back on and counted how long it took your RX to boot up again. If it was longer then 1 second you could send in your RX and it would be replaced for free with the new upgraded RX.
JR Spektrum were on the market several years before Hitec and Futaba but when Hitec and Futaba hit the market they had none of the brown out problems or mystery crashes.
Funny thing is people that are brand loyal will still swear there never was a problem?? I see it a lot less these days but when a mystery crash happens it always seems to be with a JR or Spektrum.
I'm not brand loyal so I just took my old Futaba 9-C radio, installed a Hitec module and converted it to 2.4 without any problems. If someone wants to give me a JR 9303 or 9305 I won't say no to them!!
03-12-2012 | 06:49 PM
#30
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RE: What causes a brownout?
Graybeard what about the LiFe batteries right now i am still using Nimh and a tester with a load button it are these new LiFe batteries good as the ysay and yes i still am flying with my Futaba 9 C which i have converted to 2.4 with no problems with my 25% gassers ,we had 3 crashes this weekend all because of radio problems spektrum and one on jr 9303
03-12-2012 | 08:37 PM
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From: Pikeville, KY
RE: What causes a brownout?
ORIGINAL: DadsToysBG
To be honest even the techs at Horizon didn't have a good reason for the 4.8 battery being included. Now no radio system sold has a battery with it.
(2) When they first released their 2.4 the egg heads that designed the system never thought that people would let their battery's get to low. Too them it was a nobrainer that you keep your battery's in top condition. When they saw that the consumer was not doing this they went back and redesigned their receivers with a quicker reboot time.
(3) Yes you can. All new radio's are X that will work with the older S. All the new receiver's are X that will work with S radio's. If you fell it is important you can upgrade. As time passes all the JR/Spektrum will be X as older receivers and radio's are retired. If you haven't had any trouble as I haven't there's no need for the upgrade.
I have a X radio now but I'm still using the old S receivers that have the old reboot time.
I fly GS planes and have learned about the power demands of these type of planes. I have both planes out of the trailer and I am in the process of re wiring them and adding a power panel to get better power distribution to the servo's.
It's a continuing learning process and improvement and as I learn more I make the changes. Dennis
To be honest even the techs at Horizon didn't have a good reason for the 4.8 battery being included. Now no radio system sold has a battery with it.
(2) When they first released their 2.4 the egg heads that designed the system never thought that people would let their battery's get to low. Too them it was a nobrainer that you keep your battery's in top condition. When they saw that the consumer was not doing this they went back and redesigned their receivers with a quicker reboot time.
(3) Yes you can. All new radio's are X that will work with the older S. All the new receiver's are X that will work with S radio's. If you fell it is important you can upgrade. As time passes all the JR/Spektrum will be X as older receivers and radio's are retired. If you haven't had any trouble as I haven't there's no need for the upgrade.
I have a X radio now but I'm still using the old S receivers that have the old reboot time.
I fly GS planes and have learned about the power demands of these type of planes. I have both planes out of the trailer and I am in the process of re wiring them and adding a power panel to get better power distribution to the servo's.
It's a continuing learning process and improvement and as I learn more I make the changes. Dennis
I am the guy from Berea KY that stopped buy you place the other day. I am building a GS Aeromaster. I took ur advice and order a power panel, A123 batteries and a SE56. I am excited to get this one up and going. Thanks
Chad
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03-12-2012 | 09:19 PM
#32
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RE: What causes a brownout?
ORIGINAL: llindsey1965
Graybeard what about the LiFe batteries right now i am still using Nimh and a tester with a load button it are these new LiFe batteries good as the ysay and yes i still am flying with my Futaba 9 C which i have converted to 2.4 with no problems with my 25% gassers ,we had 3 crashes this weekend all because of radio problems spektrum and one on jr 9303
Graybeard what about the LiFe batteries right now i am still using Nimh and a tester with a load button it are these new LiFe batteries good as the ysay and yes i still am flying with my Futaba 9 C which i have converted to 2.4 with no problems with my 25% gassers ,we had 3 crashes this weekend all because of radio problems spektrum and one on jr 9303
03-12-2012 | 10:39 PM
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From: St. George, UT
RE: What causes a brownout?
ORIGINAL: Gray Beard
JR Spektrum were on the market several years before Hitec and Futaba but when Hitec and Futaba hit the market they had none of the brown out problems or mystery crashes.
ORIGINAL: zacharyR
FYI LOAD TESTING IS SOON TO BE A THING OF THE PAST
FYI LOAD TESTING IS SOON TO BE A THING OF THE PAST
03-13-2012 | 04:15 AM
#34
RE: What causes a brownout?
I haven't look into it recently but the 72MHz systems could run into a multipath problem. Since you said these "brownouts" occur at the same place on the field that could be a possibility. Mutlipath is when the signal that goes directly from your radio to the aircraft is cancelled out by the signal that goes from your radio, bounces off something like pavement, water, metal tanks, metal buildings, etc, and then goes to the aircraft. 2.4GHz should be less susceptible and the frequency hopping certainly helps recover but it might happen. Perhaps there is a squiggly guy (RF expert) on this thread that can answer that.
03-13-2012 | 06:56 AM
#35
RE: What causes a brownout?
Real simply put a brown out is when your receiver battery voltage drops below around 4 volts. Never use anything less than a 6 volt battery in your receiver. Always use a quality charger and check battery voltage prior to each flight. If using digital servos be expecially diligent with your onboard battery. If you are performing 3D it will suck voltage quickly and can cause brownouts and blackouts if your battery is inadeqate.
You can place a voltwatch on your plane and with the equipment turned on. Place all your controls in full travel and look at your voltwatch.
THis will tell you the story
You can place a voltwatch on your plane and with the equipment turned on. Place all your controls in full travel and look at your voltwatch.
THis will tell you the story
03-13-2012 | 07:24 AM
#36
Senior Member
RE: What causes a brownout?
The power output of the transmitters are quite limited by law. This law varies between countries; I think France has the lowest maximum power specifications. In all cases, your range is usually limited by the quality of the receiversnot the transmitters. Of course antenna orientation and freedom from obstructions (items between the receiver antenna and the transmitting antenna) is very critical on the higher frequencies such as 2.4GHz. Polarisation also plays a part which can be critical where reflections are prevalent. Most RC is linearly polarised and reflections can be a real problem on surface vehicles or boats, if circular polarisation is used, reflection becomes less of a problem as any reflections are counter rotation to the transmitted rotation. It is just that circularly polarised antenna are not so easy to fabricate and use as the linear ones are. However, none of the above comments here relate to brown outs. Brownouts are usually (probably always) caused by something reducing the voltage on the receiver bus below the limits at which the receiver can detect and process the signal from the antenna. This can happen with either 4 or 5 cell batteries, depends strictly on the voltage drops in the wiring/switches between the battery and the receiver bus.
03-13-2012 | 07:31 AM
#37
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RE: What causes a brownout?
ORIGINAL: mranga
Hello,
The following problem occured TWICEwith a spektrum AR-6200 receiver and once with a Hobby King Orange receiver (euqivalent in capability the AR-6200):
The plane is flying fine. Battery is fine. Lots of charge. Sudden and total loss of control.
Any clues on how to avoid it? The reboot time on the Spektrum receivers is pretty bad. More than enough time to crash a plane. Iam considering placing the satelite receiver outside the plane or having a piece of clear monokote from where Ican actually see the receiver to make sure it is not blinking before takeoff. Is this kind of problem caused by a bad binding (blinkig receiver)?
Iam wondering (seriously considering)giving up onSpektrum and moving to Turingy +FrSky as a result of these nerve wracking moments.
Any advice?<span style="font-family: Comic Sans MS;"><span style="font-size: medium;"><span style="color: rgb(128, 0, 0);">Get a Modern Radio and Receiver system. The spectrum 5,6&7's are old Tech. Go to Hopping .... PERIOD.</span></span></span>
Thanks
Ranga
Hello,
The following problem occured TWICEwith a spektrum AR-6200 receiver and once with a Hobby King Orange receiver (euqivalent in capability the AR-6200):
The plane is flying fine. Battery is fine. Lots of charge. Sudden and total loss of control.
Any clues on how to avoid it? The reboot time on the Spektrum receivers is pretty bad. More than enough time to crash a plane. Iam considering placing the satelite receiver outside the plane or having a piece of clear monokote from where Ican actually see the receiver to make sure it is not blinking before takeoff. Is this kind of problem caused by a bad binding (blinkig receiver)?
Iam wondering (seriously considering)giving up onSpektrum and moving to Turingy +FrSky as a result of these nerve wracking moments.
Any advice?<span style="font-family: Comic Sans MS;"><span style="font-size: medium;"><span style="color: rgb(128, 0, 0);">Get a Modern Radio and Receiver system. The spectrum 5,6&7's are old Tech. Go to Hopping .... PERIOD.</span></span></span>
Thanks
Ranga
03-13-2012 | 07:41 AM
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From: Bowling Green,
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RE: What causes a brownout?
MRANGA, I read your post where you say you load tested your battery to 4.4v. I'm going to assume you used a 1amp load. Now I'm going to do some math to show that 4.4 is way to low.
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver. This is way below the threshold of the receiver. This is very short time but enough to cause a reboot of the receiver. Any 4.8 battery that shows 4.8 even with out a load needs to be recharged. you also have to consider the gauge of wire used. The standard 24ga. used in smaller planes will add to this voltage loss as well.
In my GS planes I am removing all connectors and soldering the wires. Will only have one into the power panel. I will using A-123 with 16ga. wire with deans plugs straight into the panel that give me 6.6v out with a 1/2v loss. that means I'll be delivering 6.2v to my servos
Power demands for any size plane is very important. That's why it's recommended to use 6v battery's and always recharge at 6v. A lot of the GS planes are moving to 20ga. wire just to be safe tho 22ga. works well. Dennis
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver. This is way below the threshold of the receiver. This is very short time but enough to cause a reboot of the receiver. Any 4.8 battery that shows 4.8 even with out a load needs to be recharged. you also have to consider the gauge of wire used. The standard 24ga. used in smaller planes will add to this voltage loss as well.
In my GS planes I am removing all connectors and soldering the wires. Will only have one into the power panel. I will using A-123 with 16ga. wire with deans plugs straight into the panel that give me 6.6v out with a 1/2v loss. that means I'll be delivering 6.2v to my servos
Power demands for any size plane is very important. That's why it's recommended to use 6v battery's and always recharge at 6v. A lot of the GS planes are moving to 20ga. wire just to be safe tho 22ga. works well. Dennis
03-13-2012 | 08:25 AM
#40
RE: What causes a brownout?
ORIGINAL: DadsToysBG
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver.
Dennis
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver.
Dennis
BTW, as near as i can tell "brownout" was the first thought of the OP. It certainly is not the only possible problem. But these responses do show the importance of describing the symptoms rather than a suposed diagnosis. If the OP had not given the symptoms he might never have received some of the alternate diagnoses given here.
03-13-2012 | 10:13 AM
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From: Denver, CO
RE: What causes a brownout?
if you're using all digital servos, the internal BEC (if you're using electric power) may not have enough juice at full throw on all the control surfaces and will cause a brownout and reboot. This happened on my ZTW esc and i had to go with an external BEC.
03-13-2012 | 10:39 AM
#43
RE: What causes a brownout?
Brown out? I don't need no stinking brown out. Airtronics baby. from 20-100+ deg with gas, glow and elec, and never a wimper or glitch for 3 years now. The spectrum guys are always having problems at our field.
Airtronics baby. from 20-100+ deg with gas, glow and elec, and never a wimper or glitch for 3 years now. The spectrum guys are always having problems at our field.
03-13-2012 | 10:51 AM
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From: Weeki Wachee,
FL
RE: What causes a brownout?
So far, all I've read about on this thread is battery problems, 4.8 vs 6.0, voltage dropping below a certain point, etc. These can happen if you aren't careful about your batteries, charging them, cycling them when they are new, etc. What I haven't seen address and in particular with Spectrum is TX antenna position. I lost two planes in almost the exact filed positions because I poo-pooed the issue of antenna position. If you fly with the antenna on your Spectrum sticking straight out and point the antenna at the plane while flying, you can lose radio contact (simislar to brown-out in results, a crash). This is how I lost my two planes, as I would follow the planes flight path with my TX. The weakest signal in a 2.4 TX is straight out the antenna and straight back from the receiver. Picture an apple cut in half, and picture the antenna laying on top of the cut half. The best signal is emitted where the apple is the thickest, not at the stem or butt of the apple. I have a friend who also lost two planes that crashed within 100' of each other a quarter of a mile away. Why? Because he always faced straight ahead, leaning against the leaning post with his antenna bent at a right angle, but pointing to the right. HIs planes crashed far off to the left, where there is virtually no signal. If you fly 2.4, bend the antenna straight up, directly in front of you. You will cover the entire flying area, except directly overhead, which hopefully you won't do. Pay attention to the RX antenna orientation, i.e., right angles to improve reception. One last thought. If your plane has a lot of carbon fiber, you may have a signal get blocked resulting in a crash, so watch for that as well.
So many people want to blame Spectrum for their radio problems, but in reality, they are oblivious to signal propagation and strength.
So many people want to blame Spectrum for their radio problems, but in reality, they are oblivious to signal propagation and strength.
03-13-2012 | 11:08 AM
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From: Bowling Green,
KY
RE: What causes a brownout?
It really isn't important what many of you think. The 1/2v drop came from several people that have the good equipment for testing in the UAV industry. Most of the power loss is between the battery and receiver during a high demand that is momentary. Dennis
03-13-2012 | 11:21 AM
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From: , MD
RE: What causes a brownout?
ORIGINAL: DadsToysBG
MRANGA, I read your post where you say you load tested your battery to 4.4v. I'm going to assume you used a 1amp load. Now I'm going to do some math to show that 4.4 is way to low.
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver. This is way below the threshold of the receiver. This is very short time but enough to cause a reboot of the receiver. Any 4.8 battery that shows 4.8 even with out a load needs to be recharged. you also have to consider the gauge of wire used. The standard 24ga. used in smaller planes will add to this voltage loss as well.
In my GS planes I am removing all connectors and soldering the wires. Will only have one into the power panel. I will using A-123 with 16ga. wire with deans plugs straight into the panel that give me 6.6v out with a 1/2v loss. that means I'll be delivering 6.2v to my servos
Power demands for any size plane is very important. That's why it's recommended to use 6v battery's and always recharge at 6v. A lot of the GS planes are moving to 20ga. wire just to be safe tho 22ga. works well. Dennis
MRANGA, I read your post where you say you load tested your battery to 4.4v. I'm going to assume you used a 1amp load. Now I'm going to do some math to show that 4.4 is way to low.
In our testing of GS planes we found that the standard connector lost 1/2v per connector. Now you have a connector on both sides of the switch that totals 1v. you also have a connector int the receiver, that's another 1/2v. and we're not sure if there is a voltage drop thu the switch. But now you could possibility only getting 2.9v into the receiver. This is way below the threshold of the receiver. This is very short time but enough to cause a reboot of the receiver. Any 4.8 battery that shows 4.8 even with out a load needs to be recharged. you also have to consider the gauge of wire used. The standard 24ga. used in smaller planes will add to this voltage loss as well.
In my GS planes I am removing all connectors and soldering the wires. Will only have one into the power panel. I will using A-123 with 16ga. wire with deans plugs straight into the panel that give me 6.6v out with a 1/2v loss. that means I'll be delivering 6.2v to my servos
Power demands for any size plane is very important. That's why it's recommended to use 6v battery's and always recharge at 6v. A lot of the GS planes are moving to 20ga. wire just to be safe tho 22ga. works well. Dennis
03-13-2012 | 11:26 AM
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From: , MD
RE: What causes a brownout?
ORIGINAL: lackeyma
So far, all I've read about on this thread is battery problems, 4.8 vs 6.0, voltage dropping below a certain point, etc. These can happen if you aren't careful about your batteries, charging them, cycling them when they are new, etc. What I haven't seen address and in particular with Spectrum is TX antenna position. I lost two planes in almost the exact filed positions because I poo-pooed the issue of antenna position. If you fly with the antenna on your Spectrum sticking straight out and point the antenna at the plane while flying, you can lose radio contact (simislar to brown-out in results, a crash). This is how I lost my two planes, as I would follow the planes flight path with my TX. The weakest signal in a 2.4 TX is straight out the antenna and straight back from the receiver. Picture an apple cut in half, and picture the antenna laying on top of the cut half. The best signal is emitted where the apple is the thickest, not at the stem or butt of the apple. I have a friend who also lost two planes that crashed within 100' of each other a quarter of a mile away. Why? Because he always faced straight ahead, leaning against the leaning post with his antenna bent at a right angle, but pointing to the right. HIs planes crashed far off to the left, where there is virtually no signal. If you fly 2.4, bend the antenna straight up, directly in front of you. You will cover the entire flying area, except directly overhead, which hopefully you won't do. Pay attention to the RX antenna orientation, i.e., right angles to improve reception. One last thought. If your plane has a lot of carbon fiber, you may have a signal get blocked resulting in a crash, so watch for that as well.
So many people want to blame Spectrum for their radio problems, but in reality, they are oblivious to signal propagation and strength.
So far, all I've read about on this thread is battery problems, 4.8 vs 6.0, voltage dropping below a certain point, etc. These can happen if you aren't careful about your batteries, charging them, cycling them when they are new, etc. What I haven't seen address and in particular with Spectrum is TX antenna position. I lost two planes in almost the exact filed positions because I poo-pooed the issue of antenna position. If you fly with the antenna on your Spectrum sticking straight out and point the antenna at the plane while flying, you can lose radio contact (simislar to brown-out in results, a crash). This is how I lost my two planes, as I would follow the planes flight path with my TX. The weakest signal in a 2.4 TX is straight out the antenna and straight back from the receiver. Picture an apple cut in half, and picture the antenna laying on top of the cut half. The best signal is emitted where the apple is the thickest, not at the stem or butt of the apple. I have a friend who also lost two planes that crashed within 100' of each other a quarter of a mile away. Why? Because he always faced straight ahead, leaning against the leaning post with his antenna bent at a right angle, but pointing to the right. HIs planes crashed far off to the left, where there is virtually no signal. If you fly 2.4, bend the antenna straight up, directly in front of you. You will cover the entire flying area, except directly overhead, which hopefully you won't do. Pay attention to the RX antenna orientation, i.e., right angles to improve reception. One last thought. If your plane has a lot of carbon fiber, you may have a signal get blocked resulting in a crash, so watch for that as well.
So many people want to blame Spectrum for their radio problems, but in reality, they are oblivious to signal propagation and strength.
Thank you very much. I'll replace the antenna and make sure it is bent at a right angle pointing straight up. That is the best piece of analysis on this thread. Never thought of that.
03-13-2012 | 01:55 PM
#50
RE: What causes a brownout?
Food for thought here. In general back when we were flying AM and FM radios with analog servos a good nicad battery with 4 cells was around 6 volts. 1200 Mah was good for all day. Now with the advent of Spektrum, Hitec, Futaba and others going to 2.4 and the servo technology improving and some are now high voltage servos. A 4 cell NiMh, LIFE, A123 and others at 1200 mah is not going to cut it for all day flying without placing those batteries on a charger after a couple of flights.
I typically fly giant scale aircraft and tend to use a 5 cell hydrimax pack with 4200 Mah. I only use a 4.8 pack for ignition. I always install a voltwatch and check batteries before each flight with all controls to their full deflection and move them around and watch the voltwatch for a drop below the green. It is just good insurance.
any modern computer radio with 2.4 technology will brown out if the voltage pull exceeds the battery output. There are many ways to keep your voltage peaked and some include a lipo pack going through a voltage regulator. I like to keep my installations simple.
I have been flying Spektrum and JR since 2.4 arrived. My current radio is a JR9503 and to date I have not had any issues with any of my planes browning out or worse blacking out. There is a slight learning curve with modern day radios and it is just a matter of providing your receiver with enough voltage to perform the flight and subsequent flights according to your flying style and battery output. If you fly 3D bring a charger with you to the field and after each flight place it on a charge.
I typically get 3 flights out of my 5 cell pack before it needs a top charge.
good luck and I wish you sucess in your future flights.
Regards
Glenn Williams</p>
