Hop-ups - Charger Mods::

1C charger mod
Author: modfly
Author Email: modfly at RCGroups
Specs: N/A
Material Required: N/A
Downloads available:
Notes: I have been using my Apache 2020 Hobby grade charger to charge these PZ lipos for the Cessna, Citabria, Vapor, MCX..Only problem is my HG charger is not portable. So after some research figured out how to mod the MCX charger to 1c or 110ma charge.

2 Other people here at rcgroups were playing with this mod at the same time as me and all I have done is test others data on what has already been learned and posted a setup procedure. So in essence, I have taken the time to post the data and procedure here in its own thread.

1. Disassemble charger by removing the pads and then 4 screws.
2. Turn Potentiometer full CCW.
3. Reassemble with 4 screws and feet pads.

Optional mods..
1. Add a Female JST in parallel to the connector output board. This will allow charging of any 1 cell lipo with a JST and allow monitoring of the charge endpoint.
2. Add a Male JST in parallel with the AA battery connectors and use rechargeable AA battery's. The Added male JST will allow charging the internal AA battery's without having to remove them.

I'm using rechargeable 700mah nicad AA size batteries in the MCX charger.

AC Adapter Mod No. 2
Author: aristo1963
Author Email: aristo1963 at RCGroups
Specs: N/A
Material Required: See Parts List Below
Downloads available:
Notes: 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 )

AC Adapter Mod No. 3
Author: MarioArguello
Author Email: MarioArguello at RCGroups
Specs: N/A
Material Required: 6 V DC Adapter, Diode 1N4001
Downloads available:
Notes: Get a 110 VAC to 6VDC adapter and connect to the +/- of the battery terminals. You will also to connect the positive lead of the LED to the Cathode end (stripe) of a silicon diode 1N4001 with its anode (non stripe) side is connected in series to the plus of the charger 6V DC lead.

The diode drops the voltage 1.5V from 6 VDC required by the LED to provide charge indication as in the stock setup (Led connected to the 1.5 V below the 6V of the 4 batteries).

Just do not use batteries with this mod because the Charger will be connected directly to the battery terminals and if you do, you will drain the batteries through the power adapter. You can use switches, etc. to make it more elaborate, but this is the simplest of mods using a constant power source.

The internal circuitry of the MCX DC charger takes care of the convertion and proper charging and monitoring of the flight battery via the LED.

There are similar mods, more elaborate, but all you need is the above and you should be able to charge your batteries without having to worry about the 4 batteries discharging and not fully charging your flight battery.

The problems associated with poor heli performance may be due to flight battery not being fully charged. Isolate that posibility by performing the charger mod. You could also use ANY constant DC power source that puts out 6VDC, some older chargers may put out this voltage also. Check your AC-DC adpaters from other similar toys some of them put out 6VDC, 500 mah is a good start or one with higher amperage rating.

AC Adapter Mod No. 4
Author: gdavis9999
Author Email: gdavis9999 at RCGroups
Specs: N/A
Material Required:
Downloads available:
Notes: This modification will allow you to use either batteries or an AC adapter.

As an engineer I work with schematics, but I thought it may be easier for you to just lay out your charger as in the pictures, buy the parts from Radio Shack, and follow the instructions.

If you have questions, let me know. Mine is working great.

AC Adapter Schematic
Author: MMCGinnis
Author Email: MMCGinnis at RCGroups
Specs: N/A
Material Required: See Drawing
Downloads available:
Notes: Please reference the schematic below for proper connections of a wall wart to the mcx charger. It shows the proper location of the diode needed for usage of the charge status indicator LED. This Schematic also allows you to use a professional external LiPo charger and or a watt meter. You obviously do not need to incorporate those parts in order to simply use a wall wart. Even the wall wart switching plug in not needed, if like was mentioned, you leave the batteries out).

AC Adaptor Mod
Author: dacaur
Author Email: dacaur at RCGroups
Specs: N/A
Material Required: DC Adapter
Downloads available:
Notes: If you want to be able to plug the charger into the wall, but still want use the stock charger and just plug it in with a 6V wall-wart charger, here is how you would do that... You just need a 3 way switch, a DC jack, and basic soldering skills. With the switch switched one way it will charge off the AA's, and with it the other way it will charge from the DC jack., there are also jacks you can get that have a switch built in so when you plug it in it disconnects the AA's automatically, but they cost a little more.

Well, I think I heard the stock charger will charge the pack in 20 min, which would be 3C, so you need at least 390Mah, plus a little extra for waste.. But I would try to find something at least 500Mah to be safe. Too much is better than too little, as the charger will only take as much as it needs... It would charge the same with a 500mah wall wart as it would with a 2000mah wall wart, but It might not work at all with a 200mah one....

Battery Charger mod
Author: MMCGinnis
Author Email: MMCGinnis at RCGroups
Specs: N/A
Material Required: See Description
Downloads available:
Notes: Here is how I've modified my charger.

1. I can now use the internal charger's batteries with or without my Astro Flight Wattmeter to monitor the charge.
2. I can use a 6 Volt Wall Wart instead of the internal batteries with or without my Astro Flight Wattmeter.
3. I can use my Multiplex LiPo smart charger instead of using the internal charger/batteries.

Using the Wattmeter has proved what was believed to be true by several people in the past. The internal charger DOES overcharge the batteries. I can now stop the charge when the voltage goes over 4.2V.

Battery Mod
Author: ColoradoHeliNut
Author Email: ColoradoHeliNut at RCGroups
Specs: N/A
Material Required: Tape
Downloads available:
Notes: The Minimum Cessna batteries have piece of mylar tape sticking out of the end. Just use a piece of scotch tape or something siimilar on the battery to achieve the same thing.The tape will fold over just fine when the battery is inserted into the battery tray.

Battery Mod Update
Author: MMCGinnis
Author Email: MMCGinnis at RCGroups
Specs: N/A
Material Required:
Downloads available:
Notes: From the factory, the LED leg is soldered to the tap that comes out of the battery compartment between the third and fourth batteries. Simply unsolder the LED at this tap.

Then solder the diode to the LED leg that you just previously unsoldered from the tap, taking note of the polarity of the diode. Then solder the remaining leg of the diode to the red battery compartment led. In effect, you can now use the batteries just as you always had, or you can power the charger from the 6v wall wart by attaching the wart leads to the battery compartment terminals, ignoring the tap between the third and fourth batteries. Not sure how or why you would want to put the mentioned diode INSIDE the battery compartment, but is is far easier and neater to place it inside the charger body and NOT in the battery compartment. See pic.

Celpro Charger Mod
Author: cactus
Author Email: cactus at RCGroups
Specs: N/A
Material Required:
Downloads available:
Notes: I completed my CellPro charger setup. I removed the connector from the mCX charger and soldered it to a CellPro bare connector. Middle three node connectors are not used and secured out of the way. When I put the pack on it took a while for it to settle into a nice .12a charge rate.

Multiplex Charger Mod
Author: MMCGinnis
Author Email: MMCGinnis at RCGroups
Specs: N/A
Material Required: Multiplex Charger
Downloads available:
Notes: I installed a connector on the side of my mCX battery charger so that I can plug my Multiplex charger into the side of the mCX charger. The connector will automatically disconnect the internal AA batteries out of the circuit and my charger into the circuit. That way, I can still use the AA charger when there is no 120V source around.