12v Power Tap on My Lexus CT200H

 

To power my iCharger 208B when out at the field I decided the least expensive and easiest way was to revisit the simple battery tap off my car a 2012 Lexus CT200H. The idea is a set of leads from the aux battery in the way back of the car to a set of female banana plugs that will allow the male banana plugs from the iCharger (not the power supply) to tap power from the battery. For safety I wanted a fuse and found instead a nifty 10A breaker. 

For completeness here are the parts, all from Amazon:

Redwolf 10A marine breaker

Making the cable

The parts. The cable, breaker, solder and flux, 

Estimate how much of the cable to remove to easily fit the breaker inline. I sanded the insides of the O-ring connectors, and the cable. I didn't have a butane torch, so tried using my air solder thingy at its max setting of 480. I now have a butane torch after a run out to Wallyworld because yeah, that air solder thingy might melt off your hand, but it barely warmed the heavy duty copper O-ring connectors. Go with a simple butane torch, that baby melted the solder and boiled the flux within a couple of seconds. By the way, for some reason Wallyworld stocks them in the camping section.

Shrink wrapped the ends for a clean professional look.

To heep the battery cable from splitting further I secured it with a wire tie and then shrink wrapped that to make it look smart. I think it came out grand! This was much cleaner than when I made one myself last time and that had no breaker.

Installation  in the CT200H

The battery that controls the aux systems when the car is not running in the Lexus CT200H is located in the way back on the right under the trunk deck. This is NOT the massive LiPo for the drive train. Remove the decking and the ccorner facing by simply unsnapping and unscrewing the large finger screws. Leave the battery in place, no need to do anything but expose it.

 

Uncover the right post safety cover; it simply lifts up and doesn't come detached. It will however keep trying to fall back into place, quite annoying.. Simply remove the nut attached to the battery connectors. I put a work towel behind the negative post in case the nut decided to challenge my patience and fall back there. It did not.

Close the red cover and replace the decking, and you are done!

The XT60-EC5 adapter is because they don't apparently make one to female banana plugs (why are they called banana plugs?), and I can easily make an EC5 m feale -banana plug female, I have a couple female plugs from over a decade ago when theynused to come on batteries. I have now depleted my supply. That blue EC5 you see actually secures and covers the two banana plugs. I CA'd them onto the larger EC5 housing (that would normally house male EC5 plugs). It has a EC5 plug on the other end that will connect to the adapter that comes tomorrow.  I'll post a pic of the whole somewhat Rube Goldbergy thing when I test it.

There it is comfy in its little home all set to go. Trunk floor simply falls over the top.

Simple, clean, even a failure like me can do it.

I made Master Airscrew's Facebook page!

 

My second Hangar 9 10cc Ultrastick is pictured here. I am using that specific prop on my current third build.  So cool!

Installing Charger Tap Cable on my Car Battery

I decided that the solution. To my field charging problem is to revisit i stalling taps off my Lexus CT200H starter battery. Its a small 12V 35-45 Ah battery, but I run the engine while charging so it keeps it charged, I read this also increases the voltage to 14V, 

I ordered these today. I could have just cut off the XT60 and solder on banana plugs, but I am not in the mood to build the cables as I did last time. I also think this is safer. I have plenty of EC5 to banana plugs I have made over the years. 

I will simply pull the battery, screw on the taps, and voila, battery power for my iCharger 208B.

I found this little credit card sized gem of a 10A circuit breaker that w will install o. The negative side just short of the XT60 plugs so I have easy access to it.

I think this will be clean elegant, safe and efficient. 

Cleaning up the Alpha Sport 450

On getting back home with the Alpha Sport 450 wing, I took a good look at my Alpha Sport. Crikey, I have neglected it... Spent some time fixing and cleaning up a few issues.

The motor mount did take a beating. The sides of the compartment are warped out, the motor mount all twisted. I removed the motor and ESC for the first time is some 15 years.

The firewall is a bloody mess. When I say that up until recently it had never been crashed, while true the OEM front gear wasn't sturdy for non-paved style runways and ripped out. I installed a much sturdier one and have had no issues since, but this required building up the firewall. Its a mess and I think the mount blind buts are loose and the wood they are secured to unreliable. The easiest thing to do was to fabricate a new firewall to epoxy over the old one. Curiously this works without interfering with the land gear mount. I installed this and tomorrow will reinstall the motor. I trimmed the mount extenders to accommodate the loss if depth. Changed the prop, pretty sure thismone is at least 10 years old and it looks it. I have a gray APC 10x7 on hand but have a couple black ones coming soon. Tomorrow we'll see what sideways BS will surely challenge me, and get the engine back on. Then cleanup and repair worn cote, reinstall the wing and yes, it may very well be the first plane I fly at Flying Tigers in Derry, NH.

Alpha Sport 450 wing repairs are done!

 John has completed the work on my demolished Alpha Sport 450 wing and the quality of the work is stunning...

I am so lucky to know John and am so grateful for his time, skill and craftsmanship. A sixer of Guinness will be yours soon!

Thanks, John!

RF Evoltuion, Spektrum WS2000 Sim Dongle, Spektrum DX7s and a decade of mystery solved in a few minutes...

 

              

Ultrastick Wiring: RCEXL Opto Kill Switch is NOT an BEC

Spent some time in a conversation with Google Gemini (their AI) and learned a lot I hope I knew and forgot about how the opto kill switch is not an IBEC.

The diagrams for the RCExl Opto Kill Switch look like this:

The RCEXL Optical Kill Switch does two things. It uses a light junction to separate the hard wire electrical connections so the 20,000 volts of noise generated by the spark plug do not flow back into the receiver and electronics interfering with them or frying them altogether, AND it serves to kill the power to the ignition. Power to the OKS passes through, so my 2S 7.4v LiPO would send up to 8V to the ignition, if the light sensor inside the is on. Here's how Gemini explained it:

The RCEXL unit has two sides that are "optically isolated" (connected only by a beam of light inside the chip) to prevent electronic interference from reaching your receiver:

1. THE RECEIVER SIDE: It plugs into your receiver to  get a signal and a small amount of power just to run the internal LED and the "gate."

2. THE IGNITION SIDE: It has a "Battery In" and an "Ignition Out" lead. You must plug a battery or regulator into the "Battery In" lead.

What happens when you flip the switch:

1. Switch On: The RCEXL unit closes the circuit, allowing power from the ignition battery to pass through to the ignition module.

2. Switch Off: The unit breaks the circuit, cutting off power and killing the engine.

I had my circuit like this:

This works, but apparently it allows interference noise hardwired back into the circuit. Options are a separate battery (two battery system, nice in big airplanes) or one battery and an BEC. Note that with this setup the RCEXL unit LED did not light up... so I think the RCEXL is bad.

Above is how I will be doing this circuit. I purchased a RCEXL Opto Kill Switch with BEC (see below). from Valley View RC. Curiously they are the only place that carries this.

Apparently this (above) is the OPTIMAL way to do this. It protects the circuit by filtering out the feedback, and offers a kill switch. I have one of these on the Pulse XT60 (need to see if I also have a RCEXL switch as this would be redundant).. Pictured below is the Tech Aero one I have, and is most recommended, in that its one of the few out there. Problem is its over $70 delivered, which is why I went with the RCEXL one.  IBEC's, especially one with a LED indicator light, are very hard to find, and nothing under the Tech Aero price.

I did drop by the workshop to check a few things, like do I have a IBEC. I have a UBEC but Gemini did not recommend this with the kill switch, and it added more complication to the circuit. I built a little holder to secure the receiver pack, and removed the RCEXL kill switch. I will likely return the one arriving today from Amazon as I don't need it, and am waiting for the one from Valley View, coming by some dude on a bike from Indiana, maybe 3-5 days?  Tomorrow I may try firing up the engine without the kill switch, wiring in directly to the battery through a 5V regulator. I am concerned that the touchy EVO 10cc will try what little patience I have left (hence today a day of rest).