HobbyKing.com New Products Flash Sale
mnemennth's blog
Posted by mnemennth | Jul 21, 2014 @ 10:50 PM | 1,345 Views
So...

After over a year of wanting, and proselytizing, and saving for a Taranis... I finally bought one. That's right; mere weeks after buying a 9XR Pro. I hadn't managed to tell my wife until this morning; so I didn't dare say anything lest the horrors of all sitcom television be visited upon me. But I've fessed up, and now I can rejoice! It should be here Thursday. *wibble*

It all started innocently enough... After fiddling around with my new 9XR Pro for a while, I noticed that the backlight was very dim compared to my 9XR. I mean REALLY dim. For all the ergonomic and cosmetic design evil visited upon me by the original 9XR, the one thing that kept me coming back to it over my much more extensively modded 9X was the display. The 9XR display is a joy to behold; deep, luscious blue, incredibly crisp, laser sharp contrast, black blacks and enough brightness that even bright sunny daylight doesn't wash it out. The 9XR Pro display was... bluish grey. Dull. Not even as nice as my 9X.

After discovering that this was NOT merely a matter of the screen brightness turned down by default (see my Blog post below this one) and that I had all the money from selling my 9X in my PayPal, I got mad; my brand new 9XR Pro... and the ONE thing I loved about the old 9XR they screwed up.

In a fit of pique decided to sell the Pro; and since I wasn't going to have to replace the FRSky module I sold with my 9X, that money could go towards the Taranis. Perfectly logical I told myself; $...Continue Reading
Posted by mnemennth | Jul 20, 2014 @ 05:29 PM | 1,207 Views
After receiving my shiny new 9XR Pro and having some time to fiddle around with it, I found myself struck my how dim the LCD seemed; at first, I simply assumed it had the brightness turned down by default. Once I found the brightness control in the menu, I was very disappointed to find it was in fact at 100%.



Side-by-side comparison* with my other Turnigy TX showed I wasn't mistaken; even my venerable old 9X was brighter, and the Pro was no where even CLOSE to the same crisp, bright display that was one of my favorite things about the 9XR.
*I know it's hard to see in this photo; but in real life, the difference is HUGE. This photo is the best of dozens I took trying to document the issue; evidently it is just one of those things that's very hard to photograph.

Questioning Mike & Brent revealed that the Pro uses the same LCD and Backlight array as current 9XR production; so clearly something else had to be at fault. A little poking around with my multimeter yielded an answer; there was something awry in the design of the LED Backlight power circuit.




Location of R56 and Q3 - Backlight Control Circuit

The 9XR takes power direct from 12.6V battery voltage at the power switch; it drives the LCD backlight array at 55ma total through a 150Ω ballast resistor. It has 5 LEDs in parallel; dividing that current by 5 yields 11ma per LED.

The 9XR Pro takes it's power from the main 5V switching regulator; it drives the entire array at 11ma. 11ma/5 LEDs in parallel = 2....Continue Reading
Posted by mnemennth | Jul 17, 2014 @ 01:12 AM | 1,254 Views
There is an issue with the Multi-Port used in the Turnigy 9XR Pro, which I discovered when removing the main board to inspect my LCD.

The original 9XR had the Multi-Port housing made so that it pulls straight up away from the board for removal, allowing access to a screw underneath. The way my Pro is made the plastic molding traps the assembly under the power jack, and blocks access to one of the screw holes underneath. In the case of my TX, they omitted said screw in manufacture. I do not feel that 3 screws is adequate to retain the mainboard properly; the [EXIT] button is not firm as a result.

One has to remove the audio jack and disassemble the housing to remove it from the mainboard as it is; clearly this is not feasible with the board in the TX.

I've modded the Multi-Port Housing on my 9XR Pro to address this issue; details are shown below:



Once completed, the Multi-Port assembly will easily slide around the power jack and pull straight up off the board while assembled in the TX. This makes for easy access to that 4th screw.

Hope this helps a few folks get this issue sorted,


mnem
*At some unfixed point*
Posted by mnemennth | Jul 11, 2014 @ 01:37 AM | 1,412 Views
OVERVIEW

I'm working with both HC-05 & HC-06 modules on more than 1 project, so I decided to actually make the programming socket I've been meaning to do for years. It's loosely based on the schematic in the HC05-HC06 Datasheet; PC breadboard is Radio Shack # 276-158B, everything else is scavenged from my junk drawers and parts bins. I decided to use through-hole parts cuz I'm tired of needing tweezers for everything. :P



Jumper configurable between HC-05 + HC-06, it connects via FTDI or equivalent Serial/USB adapter.
I recycled one of my old BT Serial carrier boards for 3.3V Reg and buffer resistors, but moved LED1 offboard along with LED2.



I've included breakouts for KEY (With momentary switch & jumper), LED1 & LED2, USB DATA (-), USB DATA (+)

LED Ballasts are 470Ω, KEY Pulldown Resistors are 10KΩ, KEY Pullup Resistor is 470Ω.

...Continue Reading
Posted by mnemennth | Jun 01, 2014 @ 03:11 PM | 1,900 Views
6/3/2014 - Added updated diagrams for MPU-6000 and Barometer in their subsection; also a full Schematic with these revisions.






Nothing fabulous in today's update; I found myself troubleshooting a couple APMs that connect, but respond with the dreaded "Failed to Boot MPU6000 5 Times" error.

In the course of this work, I found the APM_v252_Release schematic to be a bit counter-intuitive due to poor arrangement of the pinouts, particularly around the TXB0104 Level Translators. So I made updated schematic.pngs for the two TXB104s at the DataFlash and MPU/Pressure locations; I've also made a complete schematic with those updates.

When I used to do this for a living, it was a matter of pride to make sure your schematic reflected the pinout of the actual part being used; nowadays we just let the computer do all that. It doesn't care that the pinouts are out of sequence; it just tries to make the neatest diagram possible.

This is how we wind up with errors like the reversed pair of inputs on the the TXB0104 at the DataFlash; they aren't nearly so glaring when your brain is already trying to deal with a jumbled mess due to out-of-sequence pinouts.

So if you're troubleshooting failures in these areas, hopefully this will help... I may find myself attacking the other IC pinouts in those areas as well; if I do, I'll update here with those revised schematics.

Please feel free to double check my work against the original and let me know if you find any errors; a second set of eyeballs often catches something originally missed.


Peace!


mnem
*Revisionated*
Posted by mnemennth | May 29, 2014 @ 09:42 AM | 3,184 Views
This has been a weekend of back-breaking misery and fixing breakdowns, which have all converged on me at once. My simply fabulous pants-free Monday couldn't go unpunished; Murphy HAD to make sure I paid for it in utterly convoluted, contraptious, ironic fashion.

First, wife's car kakks a battery at her school on Friday AND she locks herself out of it. I go and rescue her with the battery out of my old Saturn. We spend Saturday and Sunday with Mom-in-Law visiting and hoe-ing out of the kids' room to make room for their new bed, which Mom-in-Law brought with her.

Over the holiday weekend, she parked my car in the back yard and I didn't realize it until after it had been pouring rain all night; it was sunk into the sandy loam we have here right up to the axles. I take wife & kids to work at the buttcrack of dawn so I can have her car, and when I get home the washer's pissed out a lake all over the floor. Admittedly, this I was expecting because it for a while it had been howling like a banshee every time it spin cycled, but of course the timing was perfect.

So I swap out the washer with an old Whirlpool I picked up a couple years ago as a spare and stored in the garage, and the auger doesn't work. I know how to fix it, and the kit's only $15, so I get in my wife's car to go pick them up, and it won't start. No dimming of the lights, no click, just nothing but the usual lights on the dash when I turn to start.

At this point, I have my old car with no battery, my wife's...Continue Reading
Posted by mnemennth | May 23, 2014 @ 11:05 PM | 2,262 Views
JJ RC 1000A MicroQuad Mini-Review






JJ-1000A Micro-Quad graciously provided gratis for review by TMart.com. See it here: http://tinyurl.com/JJ-1000A-at-TMart

As of 5/24/2014:

1000A (RTF With LCD Transmitter) $33.99 FREE SHIPPING
1000B (RTF With NON-LCD Transmitter) $32.99 FREE SHIPPING
1000A BNF (Bind-N-Fly with YOUR WL Toys V2x2 Family Transmitter) $25.19


First Reactions:


This morning I'm home today with a sick baby grrl, working on my FPV Quad.

KNOCK KNOCK KNOCK!!! at the door.

It's the Lone Star Overnight delivery woman with another package from TMart. "Another one Mr Paul?" she asks. "Yeah... another toy quad for me to review. Evidently they like my material; they keep sending me stuff." I answer with a smile while I sign then take it inside.

This time it's the Jian Jian Toys JJ 1000A MicroQuad; it arrived in a box that looked like it had been through a war; however, the contents appeared unscathed.

"Oh great;" I say to myself. " not another Hubsan X4 clone that costs almost as much and flies half as well." Little did I know; that is EXACTLY what it ISN'T.

I take the battery to my bench and plug it in; it uses a little USB cable with a charging circuit in the head like the V272 and V292 came with, only this has the small white battery connector like the Walkera micro helis and the V202 use.

While it charges, I take some pictures & measurements:

...Continue Reading
Posted by mnemennth | May 17, 2014 @ 01:47 PM | 25,263 Views
SJ 4000 Action Camera Tech Teardown

As promised, here is my teardown of the SJ4000 Action Camera. We will explore the hardware, Waterproof Case and insides of this camera.

Camera graciously provided by TMart.com for review. See it here: http://tinyurl.com/SJ4000-at-TMart

Overview:



We'll start with the box; it's nice, upscale retail packaging which definitely shows off the goods.



The back of the box lists all the usual specifications...

...Continue Reading
Posted by mnemennth | May 16, 2014 @ 11:40 PM | 8,713 Views
SJ4000 Technical Review (20 min 4 sec)



It's a LONG one... but there's a lot to cover. Full HD available if you click "Watch on YouTube" in embedded player.


Notice: Camera graciously provided by TMart.com for review. See it here: http://tinyurl.com/SJ4000-at-TMart

As a courtesy to my viewers, TMart has provided this Coupon Code: 32446a4312 Expires on: 2014-5-20


Here's the Review Notes:



Features:


1080P HD @ 30FPS 720P @ 60FPS W/Frame Doubling FOV 170 Degrees, same in both Resolutions

Lens in Case is REPLACEABLE Optical Quality Polycarbonate, NOT Glass; 1.5mm Thick x 34mm Dia for those who wish to see if GoPro Hero 2 case lens will fit

Camera Lens is good quality glass Fisheye type, metal shell w/12mm thread; Alternate lenses for GoPro like the Sunex DSL377 140 Degree Lens should fit

LCD is 1.5" High Res 480 x 320 or 640 x 480; Very bright and clear

Built-in Speaker for reviewing videos anytime

Full-Feature Car Cam Mode

Flip Video

Video Mode, Still Camera Mode, Menu Mode, selected from front Mode/PWR button

Manual - 12 Pages repeated in multiple languages; lots of pix, but not a lot of detailed instructions

Various mounts and angle adapters; all compatible with GoPro Waterproof Case at Pivot Bolt. SJ4000 clips will snap into GoPro bases, but GoPro clips will not snap into SJ4000 Bases. See John Childs and Techmoan's Videos on Youtube for additional review material.


Specifications:


Camera Weight: 59.2 gr W/ Battery

Camera...Continue Reading
Posted by mnemennth | May 08, 2014 @ 11:15 AM | 2,820 Views
Simple Modular Flight Mode Switch - Build it for $20




So... after reading Max Levine's Blog here about a simple 6-Way Flight Mode Switch, I decided to make my own; but I wasn't exactly satisfied with the lack of clear mode indicators.

I've also read about jDrones Arduino Flight Mode Switch based on Stefan & Roman's work; it REALLY is an awesome bit of fabrication. But after what appears to be stalled development for the last few months, I began to have second thoughts about their design.

IMHO, breaking the entire PPM chain, running it through plug-in connections to an add-on CPU, then injecting a modified PPM signal back into the TX JUST to be able to synthesize outputs to ONE channel... that is beyond tempting fate; it is BEGGING Murphy to make an example of you in a manner suitable for a Darwin Award.

[EDIT]
After some several conversations with Stefan, I find that I was mistaken about how his Arduino-based switch works; it doesn't "loop out" the PPM stream, it only adds a PPM stream for one channel which the TX is then expected to mix to the channel being used to control the APM Mode Selection.

While I still believe in the KISS principle, and like my design better for its simplicity, I think our major disagreement really revolves around which is more intuitive to use blind; a rotary knob or pushbutton switches. This is a debate which has plagued designers of electronics since the dawn of electronics; I don't think we're going to...Continue Reading
Posted by mnemennth | Apr 26, 2014 @ 07:51 PM | 2,057 Views
I recently found THIS:



at my local Dollar Tree (Well, ALL of these REALLY hobbyist-useful items, actually... Okay, okay... I got the pointer cuz like... " A flashlight AND a laser on my keychain for a BUCK? Ch'YAHHH!" anyways...) for... $1.00 apiece.

The reason I felt this item was worth blogging about is not that it's an exceptionally high-quality Android Dock; in fact, it is pretty much as cheap & cheesy plastic-y China junk as it can get. BUT...



If you pry it apart with a knife like this...

...Continue Reading
Posted by mnemennth | Apr 23, 2014 @ 08:47 PM | 2,849 Views
4/28/14 - NOTE: Data Cap issue resolved with judicious application of capital; you may now resume abusing my Bandwidth.

APM2.5.2 & 2.6 MIC5219-3.3YM5 (LG33) Regulator Mod & Alternate Capacitor Mod


Supplies Needed:



MIC5219-3.3YM5 SOT23-5 Package 3.3V Fixed Voltage Regulator

0402 or 0603 size SMD 470Ω Resistor ( Marked [471] )

(1) 1206 size 100uf 6.3V Ceramic Capacitor or (2) 1206 size 47uf 6.3V Ceramic Capacitors; more if you want to fully "Harden" the APM board at all plug-in headers.

Good, temperature-controlled soldering iron with 0.5mm Conical Tip

Chem-Wick or similar professional-quality desoldering braid in "Fine" size/guage; I recommend against Radio Shack for this due to poor quality

0.015" super-thin solder; I prefer 62/32/2 Silver-Bearing Alloy (Radio Shack # 64-035 is a good substitute)

Teeny-Tiny Needle-Point Tweezers

"Dilbert-Level" Mad Micro-Soldering Skillzz

Optical Magnification and Lighting Devices:




THE Mod:


Some time after blogging my LM1117-3.3 Regulator Mod, I found myself reading reading Joe Abrams' infamous Post # 1491 ; in it he describes his recommended diode protection Mod and makes mention of substituting another regulator, the MIC5219-3.3YM5 ( I will hereafter refer to it as the LG33, its common name after the case marking found on the SOT23-5 package variant).

It was one of several I had considered at the time I started on my Mod; it is a...Continue Reading
Posted by mnemennth | Mar 14, 2014 @ 03:24 PM | 6,252 Views
[EDIT]

WARNING: THIS MOD IS STILL IN BETA!


I'm beginning to see lots of folks talking about how this mod (seen here and elsewhere) has saved their APM, but really not a lot of talk about what testing they've done to verify the validity of their repairs. With that in mind, I feel it's necessary to place this warning conspicuously:

Please, PLEASE, don't go flying in any autonomous modes without FIRST verifying that EVERYTHING works perfectly on the bench, and then when you deploy in an actual aircraft, thoroughly test in ALL manual modes before trying anything where the aircraft is thinking for itself.

Treat it with suspicion just like you would any Flight Controller that had survived a catastrophic crash; because it HAS. The difference is that it survived a mazillion-electron pileup on the 3.3V Bus, rather than getting flipped upside down or bounced off grand-dad's grand old Elm tree.

The potential for epic, gruesome failure is not one whit less.


Please, for your sake and mine, treat it like it's possessed by demons until you have proven otherwise with careful, methodical testing; for this is our recipe:

1 part Ginormous LiPo battery with incendiary potential of a gallon of gasoline

1-8 parts high-powered Electric Motor with "Whirling Blades of Doom"

1 part Ultra-light, ultra-strong airframe equipped with a brain that can think for itself

Umpteen parts uber-complicated radio transmitter and electronics to connect it all together

I
...Continue Reading
Posted by mnemennth | Dec 08, 2013 @ 02:23 PM | 2,680 Views
We have a LOT of smart and inventive folks here on RCG; by the nature of the hobby, we encourage experimentation and customizing electronics is at the heart of nearly everything we do. As a result, it is easy sometimes to forget how dangerous electricity really is; and this is very visible in several very popular threads on modding Computer/Server Power Supplies for use with RC gear.

Now I have made oodles of these modded power supplies; I've done nearly every hack imaginable, and I've been doing it since I was a teenager. I'll admit... I've done some pretty dangerous mods, and have some scars to prove it; now I'm trying to pass on what I've learned by painful experience. I have dozens of re-purposed power supplies in my home right now, and even one or two that operate on the same principle of connecting two power supplies in series as is the point of this article.

My main concern, the reason for posting this blog, is the practice of creating a 24V high-current power supply by series-connecting two 12V power supplies and making the "Isolated PCB" or "Floating Ground" mod as is outlined in many of these threads. The "Floating Ground" mod is, in my opinion, simply unthinkable; having the metal case ungrounded of a power supply that can carry more than 400 volts inside is beyond foolhardy. It BEGS fate to adjust one's pain threshold in a very possibly fatal manner. This practice REALLY is a Darwin Award waiting to happen.

This differs...Continue Reading
Posted by mnemennth | Jul 22, 2013 @ 02:40 PM | 3,268 Views
UPDATE: "TOY" HELIS AND PLANES AND CARS VS LIPO SAFETY

In the last few years, China MFRs have flooded the market with every imaginable kind of remote control toy vehicles; as these toys grow larger and more sophisticated, so increases their reliance on LiPo batteries as a power source. MANY of these devices are based on recycled Ni-Cd or Ni-Mh powered designs; as such, they don't have low-voltage monitoring or shutdown circuitry to prevent damage to the battery.

With Ni-XX based packs, this just costs you a replacement battery (Yay! Battery sales!); with LiPo batteries, it can cost you your home or your life. When LiPos are discharged too low they can catch fire, and this process may start during a flight and not actually ignite until some time later.


Because of this, I urge anybody using these LiPo-powered toys to ALWAYS use a Low Voltage Alarm. If you don't know what I'm talking about; this is it:





http://www.hobbyking.com/hobbyking/s...arehouse_.html




http://www.hobbyking.com/hobbyking/s...arehouse_.html

Unlike readings AFTER the flight, these alarms monitor the voltage UNDER LOAD; which is how you WANT it to be monitoring. A higher load caused by a bad motor drawing too much current can cause damage to your LiPo; the 3.3V limit on these is just 0.3V above what we consider the "Danger zone" where cells get damaged. If you're just flying by timer or "by the seat of your pants", you won't know if the cells are actually being drawn...Continue Reading
Posted by mnemennth | Jun 17, 2013 @ 02:20 AM | 3,328 Views
So... today was Father's day.

My baby grrl decided to make Daddy an original painting, just for me... I'm so proud. Only thing is... her chosen medium was poop, and her canvas was half the toys in the playroom. And herself, of course.

One emergency bath later, and then I'm washing everything in the playroom with sanitizing wipes... I finally get a chance to clean myself up and make a bite to eat.

"WHUMP! WHUMP! WHUMP!" is the sound the TV in the living room makes when she slaps the screen; she does it whenever Pinky Pie or Mojo Jojo is playing on the Netflix.

"Baby grrl, stop beating on Daddy's TV." The sound stops. I go back to my meal.

"WHUMP! WHUMP! WHUMP!" again a few minutes later... "Baby grrl, I told you..."

"DADDY! Baby sisser POOPY!" my 5-year-old son interrupts me. I wolf down the last couple bites, already knowing what I'm going to find.

And it's worse than I feared... all over the TV, all over her hands, all over her face, even her hair.

Fatherhood. The gift that keeps on giving.

As the likelihood that she had gotten it in her mouth dawned on me, I realized it was time for her to get something she'd never had before... a spanking. This was a behavior that we could not permit her to repeat; I was terrified she would wind up with e Coli poisoning. The TV had nothing to do with it; it's an old projection set, and we keep it because we don't want to get a new one for her to beat on. We hope...Continue Reading
Posted by mnemennth | Jun 02, 2013 @ 04:34 PM | 3,167 Views
Mini How-To : V913 SwashPlate Reinforcement

After flying my V913 for a while and conversing with fellow forumites, it appears the V913 has a common point of failure which anyone who like to fly aggressively will eventually run into: The swash has a weakness around the base of the inner ball link arms.


Photo Courtesy RCG member cloudysea


While I have yet to personally experience a fail THIS epic, enough of my fellow forumites have that I believe it is a common enough failure to try and find a solution. My personal opinion is that if flown conservatively indoors or outdoors in zero to mild wind, as the designers of this toy helicopter intended, it probably won't be a huge problem. However, people who like to fly fast and zoom around their neighbors are also customers, so their opinions should matter too.

Here you can see the basic design issue we're talking about:



While the outer arms of the swash are nice & hefty, AND reinforced with gussets, the inner ball link arms are molded into some pretty thin material with no reinforcement at all.

So... we need to find a way to strengthen the arms without interfering with their operation. I toyed with the idea of just committing some Epoxy abuse to build up the surrounding area; but experience has taught me that epoxy doesn't bond very well with ABS plastic, and tends to just crack out under this sort of stress.

Eventually I struck upon a simple, cheap solution: Paper Clip & Hot Glue abuse. First,...Continue Reading
Posted by mnemennth | May 12, 2013 @ 12:16 AM | 5,800 Views
Like many members, I recently bought one of the TX-Ready Axe 100 CP on clearance sale planning to use it with my AnyLink-Hacked JR Module & 9XR TX running ER9x firmware.

Also, like many of you, I had NO idea where to start configuring it. So... I turned to my trusty Companio9x eePe GUI; their current versions have a Template Wizard with a built-in Flybarless Template. Unfortunately, this template does NOT include a Gyro Channel; but I'm getting ahead of myself.

If you load the Default FLYBARLESS template into a memory slot on the editor, you'll have a profile that's 90% there already; only the ELEVATOR and COLLECTIVE (CH11) virtual channels will be backwards.

This is easy enough to fix; go into the MIX tab and edit the ELEVATOR Channel from 100 Weight to -100 to reverse the Virtual Channel, then do the same thing for Virtual Channel 11 (Which is Collective by default). You now have all your Collective, Throttle & Cyclic working correctly, but DANG! NO RUDDER!

This is because the Axe 100 DOES have an input for Gyro, like most Gyro-Equipped Helis. You just need to talk to it.

Go back to Mix Tab, then add a new mix on CH 5. I set the source as PT3 (Pot #3, the leftmost one) and give it 100% weight, NO TRIM. Voila! you now have working rudder, and your Gyro Sensitivity set up on the leftmost Pot.

The default curves give you a flyable machine, with curves easy enough to tailor to your flying style.

Summary:

1) Load default FLYBARLESS HELI template...Continue Reading