EggFinder TX, RX, and EggTimer Quark assembly

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DanielLW

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I finally got around to editing these together and posting these. If anybody is interested in an assembly video that is high quality and not out of focus, check these out!

[video=youtube;EnXyD1dyZbo]https://www.youtube.com/watch?v=EnXyD1dyZbo[/video]
[video=youtube;6PERyWO4oVU]https://www.youtube.com/watch?v=6PERyWO4oVU[/video]
[video=youtube;S0Ge5Eb51yU]https://www.youtube.com/watch?v=S0Ge5Eb51yU[/video]
 
This is really nice. Thank you for posting these. I'm watching the Quark build now. I built my first Quark two weeks ago (it doesn't work). This video would have been great to watch before I put it together.
 
Awesome!

I successfully assemed the Eggtimer Classic last week but my Quark build failed. Hope to get some good insight here! ����

I also ordered some Eggfinder thing. Do you have a difficulty rating or order of difficulty for these devices?
 
Can you post a good close-up picture of the Quark? It could be one of the ICs is backwards.

I would say that the Eggfinder TX/RX is fairly difficult. I got them both working the first time, but I also have had a job in the past where I did a lot of soldering, so I have a lot of experience. Also, I had access to a nice temperature controlled soldering station, which helps a lot.

What makes the TX/RX difficult is the Hope RF module, and the GPS module. You will need a fine tip for that (but not needle fine like the one I had to use.) Also, you will need to watch temperatures. If either the Hope RF or GPS module gets overheated, you could melt the solder on the super tiny surface mount components on the boards. Take your time, and allow time for things to cool off between connections.
 
Can you post a good close-up picture of the Quark? It could be one of the ICs is backwards.

I would say that the Eggfinder TX/RX is fairly difficult. I got them both working the first time, but I also have had a job in the past where I did a lot of soldering, so I have a lot of experience. Also, I had access to a nice temperature controlled soldering station, which helps a lot.

What makes the TX/RX difficult is the Hope RF module, and the GPS module. You will need a fine tip for that (but not needle fine like the one I had to use.) Also, you will need to watch temperatures. If either the Hope RF or GPS module gets overheated, you could melt the solder on the super tiny surface mount components on the boards. Take your time, and allow time for things to cool off between connections.

Ditto,

If any solder splashes on top of the Hope module or splashes inside the base of the GPS receiver or gets underneath your Hope, GPS or Wifi modules to cause an
unseen solder bridge, your device will be persona non grata. Be careful and you'll be rewarded. Get the smallest solder tip you can find. Some use well-equipped solder stations. I've just had good luck with a cheap Wal Lenkd pen with the smallest tip there is for it. This is the unit: https://www.walmart.com/ip/Wall-Len...00001450&wl14=Wal Lenkd soldering pen&veh=sem

After using the tip for quite some while, it begins to wear and by golly forms a little concavity at the end. This is an advantage as this concavity will hold a little melted solder that will flow and makes for single handed soldering. Place the tiniest bit on a pad, tack solder the component on one end, solder the other and
touch up the original tack joint. Easy. Use a head magnifier and a good light. I "do it" in a pyrex glass cake pan. If you flip a component, it's likely to be caught in
the cake pan and can put a piece of white paper under it for contrast and find the component.

Angled "pickups" or tweezers of the smallest you can find is also a big help. Make this modest investment and Egg kits are rewarding builds. No glue, epoxies or CA
either. Something to do while the epoxy cures. Me, I've dorked a Quantum probably by a bridge under the Wifi chip. It's in the junk drawer. Broken a couple of
working EggFinders but repaired them with outboard GPS chipsets. Built three TRS's that worked right off that bat. Kurt
 
This is the quark I built. It does everything it is supposed, except fire the charges.

Everything beeps just like it says it should in the manual. With no igniters, after the 15 sec pause it goes 4 and 5 beeps. With the igniters attached, after the 15 sec pause I get the chirping.

When I try to ground test the igniters, I put a jumper on the drogue or main (I've tried both) and pull it off as the altitude is being beeped out. After the 15 sec pause, it starts beeping out long beeps - which indicates test mode. I put the jumper back on and I get one long 5 sec beep, followed by 1 sec of nothing, and then repeated beep-beep - indicating the test is over.

I checked the resistance on my igniters before installing them, they were 1.4 and 1.6 ohms. These are the orange Chinese igniters that use to be available on Amazon. I also tried using a Christmas light since I took those down today. It measured ~5 ohms, but didn't do anything.

I originally used a 1S, 3.7V, 400 mAh LiPo that I got from either Additive Aerospace or Sparkfun. After that failed, I tried using a regular 9V. I had exactly the same results with either the 1S or the 9V - in both cases everything works except the igniters don't fire.

Does anyone have any suggestions as to what might be causing this? What part(s) is responsible for firing the igniters? Are there any particular solder joints I should look at?

Please don't be too harsh on my soldering skills. This was my first SMT kit.

I appreciate the help. Thanks.

Quark.jpg
 
The Quark video is great! :clap::clap::clap: Thank you so much for these. I think I’m likely going to punk my current build and just do another. My iron does not have a temperature. How do I determine the proper temperature with my 1-4 knob on a 40 watt WLC100 iron?

@SwissyhawkThe 223 resistor by the optoisolator does not look like it has much solder on the south pad.
 
Check the orientation of the Optoisolator (white 8 pin component)

I was going to tell you that the optoisolator is OK because there is a black dot on the side that you can't see that matches the notch on the board. Then I remembered that I think I am the one that put that dot there. I think that I thought there was an indent on that side when I built it, so I put a dot on it to make it obvious. What I believed was an indent was probably incorrect. Looking at it now, the orientation of my optoisolator clearly doesn't match the picture in the EggTimer Quark manual. In the video that the OP posted, he couldn't identify the orientation of the optoisolator just from the component. He had to look at the manual first. His video might have saved me.

BradMilkomeda - I agree with you about the 223 resistor. I don't think I'll worry about it since the optoisolator is mounted incorrectly.

Oh well - this was still a fun learning experience for me.
 
This is the quark I built. It does everything it is supposed, except fire the charges.
I appreciate the help. Thanks.

View attachment 335240

The opto-isolator is definitely backward.

Now, how to fix it? Fortunately, it's just 8 pins. If you have braided de-soldering wick, you can get off most of the solder. But it's going to be tricky since there are 8 legs. Get as much of the solder off as you can, and then gently pry up each leg with a jewlers screwdriver. You may break a lead doing this, however, so you may want to get a spare opto isolator. You should be able to get a spare from EggTimer, or you can get one online:

https://www.mouser.com/productdetai...=sGAEpiMZZMteimceiIVCB4Jy96LwY5d2vs6rk12WpkM=

They are .84 cents. The shipping envelope will be the expensive bit... unless you live somewhere where you have access to a good electronics supply store. (not RadioShack)

Another thing you can try is to just put a bunch of solder on so that all four legs are connected, and while all the solder is liquid, gently lift the one side of the chip up a little. Do the same with the other side, and keep going back and forth until you can get the leads completely free. Take time between sides because you may overheat the part.

Also, the screw on the bottom left corner looks like it's touching one of the pads for the voltage regulator. It's probably OK, but just to be safe, I'd use a plastic washer there.
 
I have a de-soldering wick, but every time I've tried it, I haven't been able to get it to wick solder. I'm very new new at soldering. I built some spark fun kit and then a classic egg timer before doing the quark. I'm going to order some more stuff from egg timer so I might see if they will send me an extra optoisolator. If I get a replacement can I just cut the legs and then unsolder the remaining feet?

Thanks for the help and thanks for posting the videos.
 
Yup, just cut the legs off, and when you heat the solder, the leg will probalby come right up along with the solder. Then just use wick to clean it up.

What kind of wick are you using? It should be finely braided copper. The way that works well for me is I put the wick on top of the joint, and then hold the iron on top of the wick so that the wick is between the soldering iron and the solder joint. The copper braiding should just suck it right up. Also, are you using the solder that came with the kit? The solder that came with the kit is pretty darn good. I'm guessing it's Kester solder - the stuff that sells for $33 per spool on Amazon.
 
The wick just says "solder wick 2.5 m/m". It's something I bought off Amazon when I decided I was going to learn to solder. It certainly looks like braided copper.

I did use the solder that came with the kit.
 
Wick up as much as you can then lay the solder pen flush to the four legs quickly and gently pry up under the chip to bend the the opposite side a bit and get all
four legs off the board. Apply heat to the remaining stuck legs and it should be off. Re-bend the legs, realign and solder back to the board. If the chip is dorked,
get another one from Cris. The rest of the work looks pretty good. I have cooked the "H" out of some of these components myself and am surprised that they
work just fine. I think you can pull it off. Kurt
 
Hurray!!

i appear to have successfully built the second quark I had! I gleefully heard the 10-10-4-5 beeps! Tomorrow I’ll test the charge channels. Then with a little luck I’ll have it in my Vulcanite in time for the next ESL.

I unfortunately think I’m going to punt on the first one I built. I smoldered the optoisolator backward on the one two, I fdesoldered and fixed that but I have never heard a beep from it. I’m thinking I must have borked the processor.
 
Hurray!!

i appear to have successfully built the second quark I had! I gleefully heard the 10-10-4-5 beeps! Tomorrow I’ll test the charge channels. Then with a little luck I’ll have it in my Vulcanite in time for the next ESL.

I unfortunately think I’m going to punt on the first one I built. I smoldered the optoisolator backward on the one two, I fdesoldered and fixed that but I have never heard a beep from it. I’m thinking I must have borked the processor.

As a tip, I used my smartphone to inspect my work, and record the above videos. If yours has a decent camera, you may be surprised how closely you can zoom in on the components. Looking at it through your phone's zoom should make any cold solder joints or bridges obvious.
 
If you want to keep the board in best condition it is best to cut off the legs of the optoisolator (I sometimes use a scalpel and rock it back and forth on the pin where it enters the package) and then remove the legs and solder from the pads, one at a time. This is the least stress to the PCB. Buy new parts to solder on.

If you are soldering, remember that solder follows three things: flux, heat and other solder. When you are working with solder, remember those things and work with them. I would also include gravity in the list sometimes.

So, if you are using wick, try just tinning the end ever so slightly and then applying it to the pad, with the iron tip on top. Remove iron and wick at the same time or it sticks :wink:
 
I completed testing the deployment channels of my working Quark in a vacuum container and it appear to be fully functioning. After seeing the video with these parts I could tell I needed to turn up the heat on my iron, and spend less time on each part. The joints look much better than my first attempt. I could see the solder wick up the pins on the chip, after only being on the pad for a couple seconds.

I busted out an old micro camera lens to take this picture of the working one:
DSC_6675.jpg

If any one sees a bad soldier joint, please let me know. I'm still developing the skills for these small components!
 
I've assembled an EggFinder TX, an EggFinder RX USB, and an EggFinder RX LCD. All seem to work, producing reasonable location data, but the display on the EggFinder RX LCD is giving me a problem. When I view the LCD straight on all I see are dark matrices, however when viewed at an angle, ~45 degrees or more, the text is visible. Anyone have any ideas of what I've messed up?
IMG_20180105_101558855.jpgIMG_20180105_101619877.jpg
 
On the back side of the LCD unit there is a hole where you can adjust the LCD contrast with a small screw driver. That will fix the issue.
 
One thing I have found that helps is a solder sucker gun/pen, push the plunger down to set, heat solder to fluid then quickly place sucker on solder and push trigger, it removes a surprising amount of solder pretty quickly and allows pretty easy removal of soldered legs on chips. A wick is still needed for cleanup.
 
Very much subscribed. I bought a few of these and will assemble them over the next few weeks. Thank you for taking the time to put the video together!
 
I've had good luck with an inexpensive soldering kit like this:
https://www.amazon.com/Electronics-...74618920&sprefix=soldering+kit,aps,180&sr=8-5

The thin pointy tip seems to work well for surface mount. The temp adjust knob is on the handle. The stand needs weight on the bottom to be useful, and a separate sponge is needed as the stand doesn't have a retainer to hold the tiny sponge provided.

I don't know how long it will last, but it's not like I'll be assembling dozens of kits...

Best -- Terry
 
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