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RE: Zenoah G62 electronic ignition conversion???!
DELETE
Posted on: 5/19/2013 2:55 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11516344
RE: Radio Interference at our field
It sounds to me like they were using multiple transmitters to keep track of the position of their machinery. Sell them a GPS receiver. Its cheaper and more accurate. BTW I just ran a test. I took an old ignition I have and drove it from a function generator. I Plugged in an old spark plug and watched it spark. Then I got one of my airplanes and put it next to the sparking plug with the radio turned on to see what would happen. not a glitch. I think its a resistor plug. I dont have anything else.
Posted on: 5/16/2013 3:37 PM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11513524
RE: Radio Interference at our field
I am curious. You say the noise floor was -60 DBM, I am assuming you mean DBM. What is the bandwidth of your spectrum analyzer? That seems high. The quoted sensitivity of the spread systems is -100 DBM. Assuming a processor gain of 10db, you have lost 30db of sensitivity. That AG machinery must be putting out a lot of energy outside if the spikes you saw. As I remember the noise floor at 20degrees is 128DBM at the 1 cycle bandwidth. You may need to correct me. Its been 47 years since I worked in that field.
Posted on: 5/16/2013 11:19 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11513352
RE: Radio Interference at our field
[quote]ORIGINAL: DadsToysBG I agree, but the problem Truck found is still the first provable problem I have seen. Just like the OP. most are ''I heard'' comments never ''me''. And I did say most not all [/quote] Yes its probably the only actual 2.4 interference case. Spread spectrum was developed to reject jammers which is nothing more than man made interference. It proves that if you wipe out the entire band you can interfere with it. I sure would like to know what that AG company was using to wipe out the band. It had to develop a lot of power.
Posted on: 5/15/2013 8:35 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11512230
RE: HK Servos?
[quote]ORIGINAL: marcc109e I've got some experience with the HK15138 servo that's a little different than what I'm reading here. I've had 2 servos fail due to one of the leads on the position sensor POT coming off. On servo, the lead came off the leg of the POT and the other, the lead came off the PC board. In both cases, the wire broke. What I found was that the position sense leads (there are 3) are single stranded wire about the size of a human hair. See this video http://youtu.be/5dOeV-cvdrg Since the only failures I've heard of are the ones I've experienced, I'm taking a chance and soldering better lead wire to the position sense. I've upgraded 6 servos in this manner. We'll see what happens [/quote] There is nothing wrong with using very fine wires for the pot sense wires. There is very little current in those wires. Just put a dab of RPV over the connections at the pot and the circuit board to keep them from breaking off due to vibration.
Posted on: 9/18/2012 5:21 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11232167
RE: Gas cans for our gas motors?
[quote]ORIGINAL: SrTelemaster150 [quote]ORIGINAL: dirtybird I sure would not use an electric fuel pump on gas. [/quote] Don't start your car then. [/quote] My car has an electric pump immersed in the gas tank. Its electric wires and motor connections are sealed from contact with the gasoline. There is no danger starting my car. An electric fuel pump for our alcohol fueled models have exposed
Posted on: 9/17/2012 5:11 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11231676
RE: A123 Question
How much does Hobbyking charge for shipping? CZ_OMYGOD used to ship them free. But since the USPS banned lithium in the mail he started charging. I got 10 cells for $80 last year.
Posted on: 9/16/2012 9:05 PM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11230630
RE: Gas cans for our gas motors?
I sure would not use an electric fuel pump on gas.
Posted on: 9/16/2012 8:47 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11230620
RE: 2 5s packs for 10s question...
Yes
Posted on: 9/16/2012 4:26 PM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11230349
RE: Can the new generation of computer radios do this ?
Multiplex is a great radio. You can assign any control to any channel you wish. Now if they would just write a manual you can understand.
Posted on: 9/16/2012 1:33 PM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11230194
RE: smallest Gas engines
I don't have a system that uses this. I think 3W uses a coil pick up system. This is nothing new. Your hard drive uses a coil pick up to read the data off the plate. This data has been placed there by another coil called the write head. I could design such a system but I don't have the ambition to work out the kinks.
Posted on: 9/15/2012 1:21 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11229469
RE: smallest Gas engines
You wouldn't need points. You could place a small coil next to the same small magnet used for current CDI systems. The charge generated by the magnet passing the coil would trigger a FET that would take the place of the points. With this you could run it on three volts. A hall effect trigger needs 3.7 volts.
Posted on: 9/15/2012 11:21 AM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11229384
RE: A123 Question
I also have made a simulated radial. It is a 9s1p on a 72" Lazy Ace. I flew it for 4 years then had to change the batteries. Since the cells hold their voltage under high loads, you get a more consistent flight than you will from a lipo. I have found cz_omgod in China has the best cells at the lowest price.
Posted on: 9/15/2012 6:02 AM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11229154
RE: smallest Gas engines
What we need is a smaller ignition.
Posted on: 9/14/2012 9:36 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11228978
RE: A123 Question
[quote]ORIGINAL: ramboman I use a123 since 2006 for Rx too, but also for main power... One pack per plane, reloaded in place in less than 5 min. [/quote] Me too. I got tired of the hoops you have to jump through to use Lipoly's and got rid of them. I just wish there were more sizes of A123's
Posted on: 9/14/2012 9:33 PM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11228976
RE: Gas Engine interference
[quote]ORIGINAL: Len Todd Did you use a non-conductive throttle linkage? A conductive throttle linkage has been known to ''feed'' ignition noise into the throttle servo and back to the receiver. Also, if you are using ganged Aileron servos (i.e. two on each wing): On my 33% Extra 300L, I separated the ganged aileron servos using smartfly's Equalizer II. They acted erratically w/o the Equalizer in between the AR9210 receiver and the servos. I could not just use Ys on ganged digital servos. [/quote] Another old modelers tale with no basis in fact. You can use anything you want as long as its isolated from the engine with a plastic quick link. Even on 72mhz
Posted on: 9/12/2012 6:33 AM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11226008
RE: Gas Engine interference
It should be a clue that it was not an RF problem because the other servos were not affected. I can't say why the kill switch caused the problem. There is not enough information there to analyze it. My guess is there was a coupling thru the power supply. There is some problem with the kill sw. that overloaded the power source. But I don't know. I have no information on the kill sw. Keep in mind when you write to the manufacturer you usually don't get an answer from the technical people. Some tech writer usually answers your letter. If you would like to know how SS works and why a resister in the spark plug stops RF PM me and I will write an explanation. I have been out of school to long to explain it mathematically so I have just tell my impression so it wont be hard to understand.
Posted on: 9/9/2012 6:42 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11223195
RE: Gas Engine interference
[quote]ORIGINAL: All Day Dan Good question Jim. The answer is no. I've been in RC since 1952 and it was the reason I became an electrical engineer. My father spent a fortune on me so I could accumulate all my degrees. Luckily I speciallized in radio frequency engineering including the microwave region. I don't claim to know what I am talking about but I may be ahead of the doctor, lawyer, plumber or someone else that did not get his brain shrunk trying to memorize all that stuff for six plus years. Notice, I said ''stuff'' instead of something else because all I wanted to do was past the tests at that time. I probably forgot more than I learned by now but I can help the guys in this great hobby of ours a tad more than someone else. Experience does count but it's a tough way to learn. You never want to defy the laws of physics because you will never get away with it in the long run. And that usually happens when we are flying. Suburban is lucky. He found his problem before he got off the ground. Dan. [/quote] If you are an electrical engineer you should spend some time on the way a spread spectrum system system works. Then you will realize your explanation is impossible. Then spend a little time on why a resistor in the spark plug stops RF interference then you will realize there cannot be any RF generated in the 2.4GHZ domain by the spark plug. Even better get a good spectrum analyzer and you will see for yourself. BTW I am also an EE with many years of RF experience.
Posted on: 9/9/2012 6:10 AM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11222593
RE: Servo calibration issues
[quote]ORIGINAL: Thud_Driver JR digitals - 3421, 8411, 8611, 8231, etc. plus some Futaba, Hitec & Airtonics digitals. The analogs go on the gear and brakes in the jets. [/quote] I tested the 8611 several years ago as a part of testing I did for an article. Its deadband is 3 to 5us. If driven from a y-harness there should be just barely discernible difference with a 12" stick mounted on the control surface. If you are driving the servos from separate channels the difference is due to the difference in the channels and not the servos. I also tested the linearity of several servos. I was surprised how good they were,even the low cost servos.
Posted on: 9/7/2012 7:53 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11220650
RE: Lipo for Speckturm Dx7
I bought a Multiplex radio in 2007 and converted it to 2.4ghz immediately. It came with a NIMH battery that I found I needed to charge about once every six weeks. I don't fly a lot but I do a lot of testing. Converting it to 2.4 reduced the load on the battery. It still has the battery it came with. I still have to charge it about once every six weeks.
Posted on: 9/6/2012 9:08 AM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11219528
RE: Servo calibration issues
[quote]ORIGINAL: Thud_Driver [/quote] You wont see any difference when in full deflection. [/quote] Sorry, but I've found this not to be true for most every pair I've matched. After bench matching and installation, I put ''stick'' extensions on the surfaces roughly 10-12'' long and do a visual mechanical match and then an electronic match for neutral and end points. Surprising how much difference you find that way. [/quote] You must use cheap servos
Posted on: 9/5/2012 9:54 PM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11219108
RE: Servo calibration issues
[quote]ORIGINAL: Thud_Driver The short answer is Yes, it is hard to find perfectly matched servos, including digitals. It's why JR offers Match Boxes, Hitec offers a programmer and Smart Fly has Equalizers. It's also why radios with more channels are popular - so that you can get rid of the Y harnesses and the problem by matching servos in the Tx via mated channels, subtrim and end points (after a good mechanical setup). Idealy, you put the 2 flap servos on separate channels, mate the channels in the Tx and then do a bench setup where you set up the servo centers and end points to match exactly. Then, put them in the airplane and do a final setup/match. For me, Y harnesses are a last resort for when I'm out of channels. You sound like you might be maxed out as well. [/quote] Yes there are differences between servos. Matching devices are required to prevent servos ,when in parallel, from fighting each other. But those differences are hard to see. You wont see any difference when in full deflection.
Posted on: 9/5/2012 4:19 PM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11218752
RE: Gas Engine interference
Twisting leads is to suppress crosstalk between lines or to prevent Electra magnetic coupling (EMC). It is no help for RFI. Since there are no other lines near the aileron lines or the lines are not near a motor or generator, twisting is pointless.
Posted on: 9/5/2012 2:21 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11218617
RE: Servo calibration issues
All servos use an integrated package for its electronics. I would be surprised if there were any difference in response of those. That pretty much leaves the potentiometer as the culprit. I would get rid of those servos if the potentiometer is that bad.
Posted on: 9/5/2012 11:33 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11218444
RE: Lipo for Speckturm Dx7
There is a big difference between Lipo and Life. Life takes care of most of my objections. I sure will not buy a transmitter if its designed for Lipo's.
Posted on: 9/5/2012 7:22 AM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11218214
RE: Gas Engine interference
[quote]ORIGINAL: BarracudaHockey Weird. Amplified Y harnesses and that are no-no's on Spektrum system but your setup should work. My guess, since 2.4 really doesn't react to ''interference'' like that is that you have a vibration problem. The first thing I would try is reseating the connections in the extensions. You also might try it with one at a time plugged in. [/quote] I have to agree with you. Try changing the servos. It is extremely unusual to have interference on one channel and not the others.
Posted on: 9/4/2012 12:49 PM by Author "dirtybird"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11217248
RE: Lipo for Speckturm Dx7
[quote]ORIGINAL: Bozarth [quote]ORIGINAL: dirtybird If you put a lipo in your transmitter you have to: 1. Remove it to charge it 2. Watch the battery while it is charging. 3. Never let the voltage get to a certain level. 4. You need a special charger. 5. If you forget to turn off your transmitter you will ruin the battery and possibly ruin you transmitter. 6. Never store your transmitter in your
Posted on: 9/4/2012 12:38 PM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11217233
RE: Lipo for Speckturm Dx7
If you put a lipo in your transmitter you have to: 1. Remove it to charge it 2. Watch the battery while it is charging. 3. Never let the voltage get to a certain level. 4. You need a special charger. 5. If you forget to turn off your transmitter you will ruin the battery and possibly ruin you transmitter. 6. Never store your transmitter in your trunk if it a hot day. In the summer my garage can get to 140 degrees. I have to take all my lipos out and store them in the refrig. 7. For some transmitters you need a regulator. Why anyone wants to put up with all of that just so he has to charge it a few less times is beyond me. Eneloops will hold 75% of their charge for three years, you can charge them with your charger and there is no chance of fire.
Posted on: 9/4/2012 10:01 AM by Author "dirtybird"
in the forum "Batteries & Chargers"
http://www.rcuniverse.com/forum/fb.asp?m=11217021
RE: Mode 1
Mode 2 works better if you use a tray. If you hold your tx in your hands your thumb does not travel perpendicular to the side of the TX. So if you pull left aileron you get some up elevator. If you pull rt aileron you get down elevator. I bought a multiplex transmitter simply because it is the only transmitter you can rotate the stick axis so it matches the path your thumb makes.
Posted on: 9/4/2012 9:41 AM by Author "dirtybird"
in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=11217005
RE: getting started
Holly Molly Take your wallet and run while you can still get away from this monster!
Posted on: 9/3/2012 6:47 AM by Author "dirtybird"
in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11215515
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