clarencem

Well here goes My father-in-law called me the other day and asked me what I thought about his situation because he was out of ideas. He has never ran in to something like this in his thirty years of flying rc. I know this might hard to follow but we have spent about 9 hours trying to figure out why when I move his ailerons it causes his 6200 receiver to brown out.[:@] He has an 80 inch Ultimate with 4 Jr st126 servos on the ailerons the top two are mixed using aux channel and a "Y" the bottom two are run through the aileron channel also using a "Y" also (total of 4 on the wings). I have unplugged all of the other channels and plugged 1 servo into aux. channel and one servo into aileron port on the receiver and it still browns out.[:@] If I run his battery straight into the receiver (no switch) and plug all of the servos back in to the proper place they will all work flawlessly, as soon as I introduce a switch to the equation it will brown out when I touch the transmitters sticks.[>:] I have tried to replace batteries with known good batteries, replaced the switch with 4 other HD Jr switches. I have changed all of the servo extensions, tried different St126 servos. I am out of freaking ideas. I am not some rookie at this and neither is he. On our larger planes 150cc and up we use Smart Fly EQ10's for power distribution and for adjustment of multiple servos on the same control surface. I don't think this plane/ servo combonation needs that type of set up. This is not that big of a plane.

I have spoke to tech support so much I think I may name my next son after one of those guys. Those guys ore out of ideas, sooooo I need some ideas guys.

JIMF14D

You have binding in the system or the battery is weak, needs to be recharged or is too small.
Jim D

ddaveb

The resistance of the switch harness must be droping the battery voltage down to below the normal operating voltage for the receiver try another switch harness with thicker leads. . Also some servos will not work properly on a y lead with some recievers the pulse amplitude on some recievers is lower than normal & two servos on one output reduces the signal at the end of the lead so as to be insufficent for the servo to function.

proline8000

My Feedback: (12)

This is why I do not use switch harnesses any more on my larger airplanes. The switch harness can’t supply enough current required for all of your servos (load), you need to use a power management system like the smart-fly system.

clarencem

Nope we have removed all linkages and used a 4200mah sub "c" pack fully charged to 6.9 volts (with a load)

clarencem

Well I have tried 4 diffrent heavy duty switch harnesses. as I stated in the origional post "I have unplugged all of the other channels and plugged 1 servo into aux. channel and one servo into aileron port on the receiver and it still browns out." NO "Y" at all in fact only two servos plugged directly into the receiver. Also we have used 3 diffrent 6200 receivers and 1 spektrum 7 chanel and all of them do it. We have changed to diffrent servos (st126) and we have tried new jr 517 servos (tiny standard) still the same problem.

BuschBarber

My Feedback: (2)

Ii have an H9 P47-150 that I had been flying successfully, for several years, on 72Mhz. Dual Ailerons, Dual Flaps, Dual Elevators, Two Retract Servos, Rudder, Throttle, and Electronic Kill Switch. I was using my XP9303 with Synthesized 72Mhz RF Module. I switched to the AR9020 Rx and the Spektrum RF Module. All servos are Analog. Whenever I moved the Elevator Stick, the two Elevator servos would move erratically, at times, and the Rx would Reboot. I set up my DX8 Tx and had the same issue. I thought it might be the Voltage Regulator as I was using LiPo Rx batteries. I switched from the MPI Voltage Regulator to my CC BEC Pro. No difference, same problem. I finally replaced the extensions running to and from the Switch Harness. No problems since then.

clarencem

What extension did you use ? I have replaced all extensions just to rule that out and it still happens. I thought if I was toto make some custom heavy duty extensions it may help but all of this gear was in amother plane but it was also on 72mhz with no problems whatever. His plane is doing exactly what you have described with the elevator servos.

chuckk2

I believe part of the problem is the battery.

Conventional NMIH batteries in general seem to work well with discharge rates up to about 25% of the "C" rating.
Much beyond that, the output voltage can drop. Poking around the web, it seems that a NMIH battery's
output voltage is about one volt per cell when it is fully loaded.

Some odd test results involving electric retracts convinced me that I'm better off using SBECs with a rating of 5 to 6A.
The lipo powering the BEC on my model aircraft also powers the motor via a speed control.
Many of the speed controls have a built-in BEC with a current rating of about 2-3 A.
Digital servos may require more peak current than analog versions of the same servos.

Slide switches have widely varying current capability. If I have a choice, I'd use a double pole slide switch,
and parallel the poles.

Rodney

Since all works well when you plug the battery directly into the receiver then the problem HAS TO BE The SWITCH AND/OR THE WIRING BETWEEN THE BATTERY AND THE RECEIVER. That is the only difference between the working and non working setup. Check the connector that is wired to the battery as that is one of the connections in the NON Working loop.

P47Tbolt

My Feedback: (20)

I use an arming switch instead of a regular slide switch.With my DX8 telemtry I can see
the receiver voltage on the radio.if you have a voltmeter you need to see what the voltage is at the receiver
without a load and with a load.If you have an old battery pack or bad servo,cut the plug off and plug that into the
receiver and connect it to your voltmeter to read the voltage.
With a JR HD switch and a Hobbico Life pack,I had almost a 1 volt drop. 6.6v to 5.6v
by just operating the rudder and elevator on the bench.I installed an arming switch and could only induce a 0.2v drop
while operating the elevator and rudder servos.I also pushed againt the control surface and loaded the servos without any
further voltage drop.here is the arming switch I use.
Also with this arming switch,the only way it can fail is for the arming plug to come out or a broken wire.
Slide switches can wear and get to much resistance in them and cause a failure.
Also the less connectors between the battery and receiver the better.I try to use deans connectors for any
connections between battery and receiver or I will extend the wire by soldering in what i need to extend it.


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