Discussion Doubling Spektrum DX6 runtime

[Vantasstic]

CryHavoc,

I FMized my DX6 after the 6120DX conversion. It's similar to TeamTEORs rework, but without the foam which could act as an insulator and allow the internals to heat up a little more than usual. Pictures are here: DX6 mod with 6102 FM deck
I used a 3-cell, 2100mah, Gen 1 ThunderPower battery with an in-line diode in my 6102. I did have to cut open some of the battery compartment to fit the LiPo in, but I had the battery on hand and didn't see the need to buy another pack.

[TeamTEOR]

Whoot, my regulator came in today! I'll probably do the mod tomorrow. I love how small the package is.

Vantasstic, very nice! I would not mind redoing that with perfboard. That was something I didn't think of. The antenna mount can stay with the plastic cards tho. I used what I had on hand. So it worked! The big thing is that I have not planned to use that DX6 for much of anything. However I am seeing it as a possible radio to use on my MAC for the free simulator I found. My only problem is that I have no clue if I can get the the software to reconize the input from the radio.

[CryHavoc]

Well it worked just fine! The Quattro RF deck has the same mounting as the DX-6 deck. After soldering the wires together everything worked perfect. Two different rxs were used and all channels and range check went off without a hitch. I even used the Quattro back case half to remind me my DX-6 is different and to keep the Quattro Tx sticker for FCC part 15 compliance. I'll try to get pics soon.

I've been thinking of installing the 6102 RF deck into an old ACE MicroPro8000 Tx I've got but I'll need to do some checks. Not like I need another Tx though.

Now I'm just waiting for the switching reg to get here so I can finish the XP6102 mods.

Teor, I'm on a late night-early morning schedule, plus I've been working in the hanger alot lately so I haven't really had to deal with the heat to notice it.

Later,
Mike

[marketsage]

I got my DE switching regulator yesterday. It is late at night and I was tired but I was itching to get it done. Being sleepy, tired, hyperopic and impatient I knew I was a lot more destructive than usual - but plods like me never learn from past mistakes.

Got the wrong soldering iron 15W - too little heat and in no time at all, I ripped the solder pads right off the PCB when trying to pry the legs of the linear reg.
Not only that - the little trace on the leftmost pad that connects to the hole is broken. AAAARGGGHHH!

Ok now I'm in near panic mode. I brought out my stereo microscope to see properly and try to salvage what's left. I managed very carefully glue the traces back on the board with a trace of CA, and solder the new switching regulator onto the pads. Through the microscope, I can see clearly that the legs are making good contact to the pad and the solder is shiny and good. I have scraped a bit the insulation off the trace and using a clump of solder bridged the connection. I powered on the radio with the new reg and tested the range - all fine.

My main worry is the broken connection on the trace that leads to the hole and my soldered join is only making intermittent contact. It disappears into the board and I can't make out where it leads to. Does anybody know is this connection is even used?

[Cas123]

No need to panic Marketsage. strip some medium hookup wire, not the motor/ESC cable type, the strands are too fine, remove a strand , tin it and solder it from the pad of the regulator along to where there is undamaged pcb track. This will strengthen it and make sure the current carrying capacity is there. you may have to scrape off the protective laquor and tin the copper track first.

Ron...

[hilgert]

All three pins (if you are talking about where the regulator goes) ARE used. You might be able to "repair" some of this with some jumper wires from the regulator to other places on the board.

[gwh]

hilgert is correct about being able to repair it with jumpers. I managed to float two of the pads. This is really not as simple a mod as the instructions make it seem because those pads are fairly delicate.

[macr0t0r]

Well, I just modded the heck out of my JR XP6102 (DX6)! First off, my big thanks for supply this voltage regulator and giving the instructions. Getting the old one off took some doing (the middle connector seems to just suck away the heat...I had to crank up my solder-station). Anyhow, it was a reasonably easy mod. Granted, when I moved the finished board to my JR XP6102, I had to mount the RF board with only 3 of 4 screws since the new regulator blocks the hole, but that's hardly an issue. I used a small drop of CA on each top corner of the regulator to secure the device to the board (to take some stress off the pins). I suppose I could've used some wire to permit me to move the regulator elsewhere, but I think the straightforward approach with 3 screws is currently the best.

About 5 hours of use on the stock battery. This seems to be a more elegant (and cheaper) fix than the brute-force method of using a Lipo pack. Thanks again!

- Jim

[marketsage]

Originally Posted by Cas123

No need to panic Marketsage. strip some medium hookup wire, not the motor/ESC cable type, the strands are too fine, remove a strand , tin it and solder it from the pad of the regulator along to where there is undamaged pcb track. This will strengthen it and make sure the current carrying capacity is there. you may have to scrape off the protective laquor and tin the copper track first.

Ron...

Thanks for the tip, Cas123. Thats a very good suggestion. I do have some hookup wire lying around. I'm planning on soldering it to the hole and then to the pad to make sure that there is a good connection. I beginning to feel better already.

[constantcrash]

Originally Posted by marketsage

Thanks for the tip, Cas123. Thats a very good suggestion. I do have some hookup wire lying around. I'm planning on soldering it to the hole and then to the pad to make sure that there is a good connection. I beginning to feel better already.

Markestage,

Do nothing yet...... I did the same thing you did and I was in the electronics repair business for over 30 years.....

It will take me a few minutes to take some pictures and post them with instructions on how to repair your damage...

Be back in a few.

Jim

[constantcrash]

Originally Posted by marketsage

I got my DE switching regulator yesterday. It is late at night and I was tired but I was itching to get it done. Being sleepy, tired, hyperopic and impatient I knew I was a lot more destructive than usual - but plods like me never learn from past mistakes.

Got the wrong soldering iron 15W - too little heat and in no time at all, I ripped the solder pads right off the PCB when trying to pry the legs of the linear reg.
Not only that - the little trace on the leftmost pad that connects to the hole is broken. AAAARGGGHHH!

Ok now I'm in near panic mode. I brought out my stereo microscope to see properly and try to salvage what's left. I managed very carefully glue the traces back on the board with a trace of CA, and solder the new switching regulator onto the pads. Through the microscope, I can see clearly that the legs are making good contact to the pad and the solder is shiny and good. I have scraped a bit the insulation off the trace and using a clump of solder bridged the connection. I powered on the radio with the new reg and tested the range - all fine.

My main worry is the broken connection on the trace that leads to the hole and my soldered join is only making intermittent contact. It disappears into the board and I can't make out where it leads to. Does anybody know is this connection is even used?

Ok marketsage,

As I mentioned, it did exactly the same thing you did.

Here's my fix and I believe it'll help you overcome your anxiety. At least I hope so.

Having popped off both the lands on the Vin and Vout I figured I was also in one hell of a fix. Working with lands this small and SMD is a real pain.

First I went a head and unsoldered the ground lead. Didn't screw that up, then removed the LM2937 back from the circuit board.

Now that I had it removed, I placed my handy magnifier on and looked at the damage. I could see both the Vin land going to the right edge of C14 and the Vout land going under the center of C15 were pealed up. Also the small Vin land going to the hole in the circuit board was pulled off (same as yours).

Under magnification I removed the unsoldered lands from the edge C14 and under C15 with an Exacto #11 so they couldn't short out on anything. The one running under C15 goes underneath and turns right and makes contact with the right end of the capacitor. That's a common way to run circuit board lands. The designers can always find the proper and shortest distance between two points.

I then removed the 4 screws holding the circuit board in and looked at the opposite side noticing that the Vin land under the hole goes to the J1 red/yellow/black wire plug on the left hand edge of the upper side of the board. The land from the Vin goes to the RED wire. To do the only underside repair necessary I took a red wire from an old servo connector and soldered it to the red wire plug soldering point on the bottom of the board. Left it plenty long so I could cut it to the proper length and solder it to the Vin connection on the top of the board later (you can see it in the picture).

Next I straightened both the Vin pin and the Vout pin on the new voltage regulator leaving the Gnd pin in it's original position. I then placed the new regulator in position and figured how much of the Vin and Vout pins I would remove from the regulator.

I cut lead wires from one of my 1/4 watt resistors to be used for the next part of the fix. (perfect size to work with)

Next I soldered a length of the resistor wire to each of the Vin and Vout pins then bent them as necessary to fit on the right end of C14 for Vin and the right end of C15 for Vout. This takes time with needle nose pliers to get a good correct fit but take your time and it'll work fine.

Eventually I got everything to fit in position properly and soldered the Vin wire, Gnd lead and Vout wire.

Last I cut and stripped the red wire that I brought around the edge from the underside of the circuit board to the Vin pin on the new regulator. You can see in the picture where I soldered it.

I saved my DX6 and the voltages are all fine.

Hope this will assist you. The picture should be helpful. Hope so anyway.

Sincerely
Jim

[TeamTEOR]

Not for nothing, if you guys clip off the leads from the stock transistor it should be easier to desolder them without burning the pads. Also try some desoldering braid or a desoldering vac. I would not use more than 30-40 watts on the iron to remove the legs as well.

[Vantasstic]

Someone posted earlier they cut the legs on the original voltage reg before trying to de-solder them. If you're not wanting to keep the voltage reg, that may be the best way. Cut the legs, remove the main reg body, then use the soldering iron to heat and 'flip' off the legs from the solder pads. I was also worried about lifting a trace, but took my time and didn't have any problems. I don't think a full ametuer should attempt this due to the damage potential, but with a little soldering experience I think it's a very doable mode with care.

Oops, TEOR posted same as I was writing the above.

D.E. If you're following this thread it might be good to add this as an option for those who want to mod but aren't so soldering experienced.

[hilgert]

Cutting the legs is THE best way to go. The regulator is cheap anyway, and you can pick another one up for a buck to two.

[constantcrash]

Originally Posted by hilgert

Cutting the legs is THE best way to go. The regulator is cheap anyway, and you can pick another one up for a buck to two.

Hilgert,
Well, I finally edited my "fix" post for the last time. This old man makes so many errors no one could understand what I'm trying to say.

I totally agree with cutting the legs on the original regulator. I've been retired from working in electronics for a number of years and when I saw how small those lands were I almost decided not to even try the mod. I've been confined to a wheelchair for 40 years and am really getting old and spastic but figured, "What the hell. I did this stuff for many years. I still have the proper equipment to work with IC's and circuit boards so surely this will be a peace of cake." So much for that. Just glad I still had enough brain power to save my butt.

If I had done what I thought I should have I would have cut the leads off the original regulator, left them on the board then fit the leads of the new regulator to them and soldered in that manner. Would have kept the heat from the circuit board and all would have been fine. Hindsite is WONDERFUL.

Good Luck to all,
Jim