AC or battery power for charger

[shaggybirdman]

hmmm now i need a amp, and volt meter for my charger. maybe flame the case as well. gold contacts, and.... ok ok just the 2 meters. lol.

the meters would be kinda nice though. maybe just the volt meter.

how high teck can we get this little heli? usable mods. not bling. although a aluminum upper head would be nice. it seems to really be the only real upgrade it needs in my opinion.

[bladelearnin]

Originally Posted by aristo

Ok working battery or ps charger is done.You will need a 390 ohm resistor(thanks widow) or 2 1n4001 diodes in series to operate the led indicator(either work just fine)if you use the diodes the silver rings go toward the led.

parts listing
1-power wallwart (radio shack 6volt 8oo mah or switchable from walmart)
2-power jack-radio shack size M Model: 274-1582 or size N Model: 274-1583
3-Diodes radio shack Model: 1N4001
4-optional resistor-390ohm any good componant electronics store
5-some red and black wire light guage.
6-solder and heatshrink

pull the pads off the bottom of the charger and remove the 4 screws and split the charger in half(careful there are wires in the top half)peel off the hot glue holding the led in or desolder the leads marking the pos.neg. sides.
unscrew and carefully remove the battery jack.Now you have room to work.drill a 21/64 hole whereever you want you chargers jack(I chose the rear of the top half as it an exact fit.)Fit your jack with the three prongs facing you.The right prong will be the jacks center tip, check it on a meter,the center and left prongs will read continuity with the charge tip unplugged.If you just plug in the charge tip with no ps hooked up the center will have continuity with the outer barrel of the tip.

1-unsolder the red power lead going to the circuit board from the batterybox positive(leave it attached to the cb)
2-solder a new red wire to the batterybox positive.
3-solder a black wire to the batterybox negative(you will have 2 negatives one to the circuit board and the one you added.
4-unsolder the tiny red led wire from the batterybox.
5-solder the red pos batterybox wire to the left jack post
6-solder the red circuit board wire and the resistor or diodes to the center post(remember if diodes the silver rings face toward the led black end towards post)
7-solder the black negative you added to the right post
8-solder the tiny red wire to the resistor or diodes and heatshrink them.
9-resolder the tiny black and red lead wires to the led(i hope you wrote down their orientation.

To test it with the batteries in check for voltage from the battery negative to the circuit board pos(6v or close) if you have voltage now plug in just the tip (no power supply )to the jack.Battery neg to circuit board pos shou;d show 0v.now add the powersupply with the center tip set negative you should now have solid 6v from neg batterybox to pos circuit board.
congrats put it all together and enjoy it.If you add your battery to charge and the led doesnt come on try reversing the red and black wire(the reason i said to peel off the hotglue is then you never have to cut the led neg and cant screw it up )

seems long but very very simple to do.Better to my flights are up from 5min to 7 so far.

390 ohm reistor is that 1/4 watt or 1/8 watt

[KE4NYV]

I have been finalizing the design for my drop-in retro fit kit. Below is a picture of a board printout fitted to the inside of the charger's base. It's about 95% surface mount, with the exception of the main power jack and the connections to the charger's circuit.

[Steve Joblin]

Lookin' good KE4NYV !!! will you be offering a PCB and a parts list or a complete kit?

[gardingh]

Aristo, I'm going over your instructions and they seem to all be based on the fact that your dc supply is positive on the barrel rather than the pin which is less common. Whereas widower is indicating that his supply has the pin as positive which is most common. Or am I missing something?

I'm not sure if that might cause some of the issues other guys are having. Mine works fine as I can switch my supply to do either but I'm not sure what the result would be if you reversed the supply polarity.

Another thing, my LED also turns on if the battery is connected and the supply is unplugged. Works great otherwise.

[KE4NYV]

Originally Posted by Steve Joblin

Lookin' good KE4NYV !!! will you be offering a PCB and a parts list or a complete kit?

I plan to offer the PCB built and it will come as a retro kit for the end-user to install.

I also plan to start offering a swap plan where you can send me your charger and I send you back a converted one.

[kamtsa]

Originally Posted by KE4NYV

I plan to offer the PCB built and it will come as a retro kit for the end-user to install.

I also plan to start offering a swap plan where you can send me your charger and I send you back a converted one.

KE4NYV, what does the retro kit do (compared to the stock board)?

Kam

[KE4NYV]

Originally Posted by kamtsa

KE4NYV, what does the retro kit do (compared to the stock board)?

The retro board will allow you to power the charger externally with 12VDC to eliminate the need for batteries. It will however, retain the use of the internal batteries for on the go flying. That is the reason for all of the diodes on the board. They are basically doing alot of protecting. Since the board can take a direct 12VDC, you can use it with a lighter plug in the car to charge in the field.

[shaggybirdman]

any early thoughts on cost?

[shaggybirdman]

Originally Posted by gardingh

I'm not sure if that might cause some of the issues other guys are having. Mine works fine as I can switch my supply to do either but I'm not sure what the result would be if you reversed the supply polarity.

my problem was just that. i didn't pay attention to the required input polarity. was there others that had a problem? i thought i was the only one who dropped the ball on input polarity.

i'll consider KE4NYV's board, but i already have the parts to mod mine like aristo's diagram. i mite add another switch for charging via my triton. a 12V option is nice, but charging off my car battery really seems like i'd be intending on flying outside where this heli isn't designed to fly. plus i can put the wall wort inside the original box, and carry only 1 thing. my 12V power supply is rather big, and bulky.

[aristo]

1/4 watt and i dont know its just the way i chose to wire it lol.

[shaggybirdman]

aristo you just get home, or just get online?

[aristo]

been home since 11:00

[subdude17349]

Okay, modded my charger last night. I'm switching positive manually with a slide switch, and using a 12v wallwart with a 5v regulator (before the switch).

All is wired correctly. All I'm switching is the positive input to the board and led. I've added a resistor to the led feed to limit current.

With the switch in the battery position, everything works as usual.

With the switch in the wallwart position, things get strange. If the wallwart is plugged in and providing power, everything appears to work as normal. (didn't have time to actually charge a battery, but seems to be correct) If I unplug the wallwart from 110v, and there's a battery in the charger, the led comes on. Remove the battery, or plug back in to 110, or switch back to AA power, and the led goes out.

So, obviously the MCX battery is backfeeding the led, and I then have to assume the charge circuit.

Any thoughts? Add a diode to the led feed?

Jim

[shaggybirdman]

ya could add more parts, or just pop out the battery. i really don't think it's harming the charger any, but i would not leave the battery plugged in. would be the end of the battery if left in too long. not sure how long a led would take to drain the battery.

has anyone with a stock charger tried this with 1 battery removed to see if it back feeds, and lights the led?

[kamtsa]

Originally Posted by subdude17349

Any thoughts? Add a diode to the led feed?

I don't think that this will help since the LED is directional anyway.

Possibly a diode between the 5V feed and the charger, such that the resistor to the LED is connected on the feed side of the diode. This way the backfeed from the battery cannot reach the LED.

Caveats:
1. You may need to use higher voltage than 5 V due to the 0.7V or so drop on the new diode.

2. The LIPO will not backfeed the LED but may still backfeed the charger circuitry, draining the LIPO slowly.

I have the same problem and I just make sure not to disconnect the power. Worst case, the $10 LIPO will die.

Kam

[shaggybirdman]

well as long as you don't leave the battery plugged in there's no problem. i hope my new charger shows up today.

[bladelearnin]

this is what I got to do this mod

[bladelearnin]

i dd this mod and everything works but right before it gets to the end of the charge the led will start a slow flicker and the flicker will turn into a flash abut every 1-2 seconds but it won't go out.My flight time is over 7 minutes though so I guess no problem ttyl blade

[shaggybirdman]

woot woot the charger is in, but couldn't get it. the battery was dead when i went to get it. by the time i got her started it was to late to get to the hobby shop before closing. oh well. i'll get it tomorrow.

i'll swap the tops, and be modded in no time flat.