Eggtimer TRS and Eggfinder LCD Build Thread

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Lowpuller

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I am building a Dual Deploy Twitch for my Level 2 Cert. flight, build thread possibly to follow, but a lot of you guys are putting out some pretty spectacular build threads. I'm even hesitant to try this one but here it goes.

I plan on using redundant altimeters a Missile Works RRC2 and the Eggtimer TRS.

Frankly I've been looking at Eggtimer products for a while but was afraid they might be too complicated for my skill set but after reading the instructions multiple times and many other threads as well as talking to Chris, I have decided to give it a try. You may have even seen my soldering iron thread all related to this project.

So here is what I got in the mail after consulting with Chris on my needs, absolutely amazing customer service and politely answering my many questions.

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And here are the tools I've gathered or purchased to help make this project a success.

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And my newest and now most favorite tool!

ImageUploadedByRocketry Forum1475813171.706291.jpg


My soldering skills are fair but I have never done anything this small. I have paid close attention to the instructions and tried to obtain the right tools for the job.

I put what I hope is the final paint on the rocket tonight so the only thing left is the AV Bay. I know some folks have built these projects in a couple of hours but I suspect this will take me at least a couple of weeks based on available time and patience.
 
I'm in the same boat with just about the same tool set. Looks like you bought the Hakko with the 5 tips package. Let us know which Hakko tip you like for the surface mount stuff.
 
2 weeks? Blah. You'll have these busted out before you know it. Once you get your first resistor down, you won't want to stop :)

This video has some great SMD soldering tips:

[video=youtube;QzoPxvIM2qE]https://www.youtube.com/watch?v=QzoPxvIM2qE[/video]
 
2 weeks? Blah. You'll have these busted out before you know it. Once you get your first resistor down, you won't want to stop :)

This video has some great SMD soldering tips:

[video=youtube;QzoPxvIM2qE]https://www.youtube.com/watch?v=QzoPxvIM2qE[/video]

Haven't see that particular one, it's pretty good. What he didn't mention was the leadless packages where the pads don't curl up the sides, i.e. the barometer chip. They're pretty much impossible to reliably hand solder... believe me, I've tried.
 
Oh man, This is great. I'll open my LCD stock case and post some pictures of it as an example. Not to hijack but to show a different idea. Will do it tonight. Kurt
 
2 weeks? Blah. You'll have these busted out before you know it. Once you get your first resistor down, you won't want to stop :)

This video has some great SMD soldering tips:

Ditto. The most work will be configuring the box. If going to do night launches you'll want to wire in the display illumination and make sure you use a plug-in connection for the bluetooth adapter.
I'm slow and takes me 3 hours to do a plain EggFinder. Others are much quicker but in the end you want a functioning project. Built 3 TRS's but I'm fastidious so it's a couple of evenings for one of those. All three worked from initial powerup.

Be sure you put some masking tape on the GPS receiver where you solder as there is a slot in the base. I once experimented with an outboard GPS and when I decided to solder on the SirfIV Maestro chip, with the confined space with all the other components mounted. I slopped some solder in the base and dorked it. Removed the Maestro and that EF uses an outboard Ublox chipset now. Kurt
Kurt
 
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Pictures of vertical built LCD with B/T and 2100mah battery in stock case:

1.jpg2.jpg3.jpg4.jpg5.jpglcd2openback.jpg

From left to right, left side locking toggle switch is off/on. Top toggle is off/on for light.
First picture is light off, second pic to the right is light on. Third through the fifth pics show the ribbon
cable from the main board to the LCD with a second "raw" cable on the right. Acquired off of ebay and there is a comment in another thread here about the "additional" options that can be had for the EggFinders. The B/T module is velcroed to the the top of an old 2100Mah 2S battery.
Interconnect from the SMA bulkhead mount antenna on the PC board. I use a plain SMA as opposed to SMA-RP as I had the plain SMA hardware on hand. The connection on the B/T
module needs to be removable in order to be able to flash the BIOS in the future and to
be able to change frequencies of the v2 EggFinders. The TRS I believe can be done from
a laptop. I have another EF LCD in a yellow custom case where it is easier for me to get at the serial terminals so I use it for programming the EggFinder frequencies. Kurt
 
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I use 2 of these for my Eggtimer builds. I use one for holding the solder that comes with the kit and the other to pick up parts. I found mine at my local Fry's. They are very handy for Eggtimer builds.

Ummmm, Self pinching tweezer/pickups you are going to flip parts all over the place if they are very tiny.
They'll "spring" them if you don't have them placed exactly . Best to use plain jane angled tweezers/pickups where one can use their touch to hold the part "just" right and be able to release by relieving the pressure. Kurt
 
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Almost no one builds the egg timer KCD stock, make sure you figure out your mods beforehand.
EG back lighting, blue tooth, set/recall button, battery, on off switch etc.
 
Ummmm, Self pinching tweezer/pickups you are going to flip parts all over the place if they are very tiny.
They'll "spring" them if you don't have them placed exactly . Best to use plain jane angled tweezers/pickups where one can use their touch to hold the part "just" right and be able to release by relieving the pressure. Kurt


Kurt you need to try these , really not much pressure , you can literally free up a hand to solder first end of capacitor or resistor
 
Ummmm, Self pinching tweezer/pickups you are going to flip parts all over the place if they are very tiny.
They'll "spring" them if you don't have them placed exactly . Best to use plain jane angled tweezers/pickups where one can use their touch to hold the part "just" right and be able to release by relieving the pressure.

Parts will fling out of whatever tweezers you choose to use. Trust me. I have assembled some serious SMT boards by hand for work. It is quicker than getting prototypes made outside sometimes.

The "reverse" tweezers are my favourite (although I am now practiced enough to be able to use any sort). It took me two weeks to work out how to use them. Not that I am thick or anything, just they didn't come with instructions :) . I will save you working it out yourselves now. Pick up these tweezers with your finger and thumb at the crossover point. Roll down the tweezers to increase pressure. Roll back up to decrease or open. Not a natural technique if you have used ordinary tweezers up till that point of your life.

Tweezer technique really helps with your assembly skills. Try to pick up the parts without the tweezer tips being on the absolute bottom of the part. That helps get it flat when you hold it down for soldering (the part is on the board, not the tweezer tips). A hard surface helps greatly with this also. Get used to moving the parts (orientation, or fliping) just using the tips of the tweezers. It works well.

Once you get good, swap hands for the tweezers and iron to save having to spin the board around the do the other end of the parts! (ok, now I am just showing off...)

Most of all, don't be afraid to have a go. It is not that hard, especially once you get going. Have fun!
 
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Quite impressive. I do not trust myself to build something like that.



Later!

--Coop
 
Ummmm, Self pinching tweezer/pickups you are going to flip parts all over the place if they are very tiny.
They'll "spring" them if you don't have them placed exactly . Best to use plain jane angled tweezers/pickups where one can use their touch to hold the part "just" right and be able to release by relieving the pressure. Kurt

I've built 13 Eggtimer boards with SMT parts and these self pinching tweezers (TRS/LCD/Quantum/WiFi switch/Quark). I haven't lost one part yet but as you point out you must be careful.
 
Kurt you need to try these , really not much pressure , you can literally free up a hand to solder first end of capacitor or resistor

Maybe, I find with a regular angled pickups I can apply gradual pressure and if a component flips, it doesn't flip far. I might look into it since folks are having good luck with them. I have a pair of the spring loaded ones that are for larger items and had that trouble with them for larger builds. These might be fine enough I might be won over! Kurt
 
Ok I'm not gonna lie, this was a bit harder than I anticipated but got easier as I went.

Step 1

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Step 2 getting the iron set up as recommended

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I started at 350 F because the supplied solder was 180 C, so roughly the same, but quickly realized in 50 degree elements 750 F was needed to get the solder to flow.

So here we go

ImageUploadedByRocketry Forum1475953989.222327.jpg

This first step caused me more problems than anything else. First I had to get the temp right as mentioned above and 2nd once complete I could not get the GPS module to sit correctly. Took me forever to wick and work to get the holes full but flat.

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GPS tack time. Man the joints are small and my eyes ain't what they used to be.

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I flowed the bottom joints but but no pics, then went at it. I will be the first to say I am not proud of this work and frankly it looks better under 25x than with the naked eye.

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And after about 3 hours the GPS module is mounted.

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According to the instructions this is the hardest part. I took my time, and enjoyed it after the initial frustrations.

I must admit I sure hope I got it right and that this baby is gonna work.
 
In pic 8, the second from the right and the fourth from the right (especially the fourth) seems light. You might be able to tell better under magnification they are O.K. though.
In pic 9, third from the right.

BTW, your pictures are superb. Again, you probably can see things better under magnification in "real life" so make sure your contacts have a good connection. Looks like you didn't slop any solder on top of the contacts either. That's
great. There is a slot there into the base and I "slopped" solder in there and dorked the GPS one time when I tried to mount the GPS after all the other components were on the board. I had experimented with an outboard GPS with an EggFinder and decided to go back to stock. Just had to desolder two wires from the pads but not a good idea with a populated board. That Eggfinder will now fly with an outboard GPS!

I think the Rf module is the next most challenging piece. Look at those 1/2 grain of rice components. It's absolutely essential not to slop around solder there. I've mounted a dozen or so an never had a problem but just be careful.

Kurt
 
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More progress definitely easier than the GPS.

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Again not proud of this but looks workable.

Thanks for the critiques, per the instructions I found several areas on the GPS under 25x that needed touching up.

A few more pieces then I'm done for the day. Great rainy weather project.
 
Making great progress almost 9 hours in though

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I did have one MAJOR oh oh, while soldering a resistor close to the GPS module I let the side of the iron contact the module. I had it covered with tape as recommended in the instructions. The tape burned and created a little brown spot on the module. It was fast but that's a lot of direct heat. Really hoping I didn't ruin it!

ImageUploadedByRocketry Forum1475970286.540618.jpg
 
You might be able to tell better under magnification they are O.K. though.

Forgot to mention earlier. You can assemble with or without magnification if your eyes are good enough. I do 0402 parts (1mmx 0.5mm) just by eye.
However you assemble you need to ALWAYS inspect with x10 magnification at least. Washing with metho and a toothbrush (or proper flux remover) to get the flux off before inspection is worthwhile.

Looking Ok so far! You are going well. The amount of solder seems to be a bit too much. You can reduce the amount applied by laying the solder across the joint before placing the iron on to heat it. Then pull back with the solder rather than feeding in. How much you lay across the joint at the start is what you get on the joint. Aim for joints that are concave, rather than convex blob-looking. Here is a pic from the IPC610 standard showing a target-condition joint:
4-200.jpg

Have a look at some commercially assembled boards to see what good joint should look like (Chinese toys don't count!)

Keep up the good work!
 
Making great progress almost 9 hours in though

View attachment 302988

I did have one MAJOR oh oh, while soldering a resistor close to the GPS module I let the side of the iron contact the module. I had it covered with tape as recommended in the instructions. The tape burned and created a little brown spot on the module. It was fast but that's a lot of direct heat. Really hoping I didn't ruin it!

View attachment 302990

It should be fine. Third TRS I had a heck of a time with solder bridges that I immediately recognized but frustrating sometimes to deal with. Thought I cooked
some parts pretty good too. Had a bad feeling about it but I worked right off the bat. Your project looks fine. Easy to say with your good pictures. Kurt
 
Ok almost done now!

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First let me say the instructions are AWESOME!, but it is important to read them before assembly and read ahead.

I soldered the red LED in the wrong place but did not realize I had done until the next step. I had to desolder it, thankfully I left the legs a little long, what a pain.

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However upon performing the preliminary test, the LED failed but the RF module LED flashed so I knew I had an issue, I guessed I soldered it in backwards, so I took it out a second time and resoldered. YEAH! Everything worked, I even made a short video, which I may post later.

I finished up everything else less the battery leads, terminal blocks for charges, and the antenna as I have not made final decision on these there yet.

Ran the final test and .................. everything worked as advertised 😀😀😀😀😀😀😀😀😀😀😀😀😀

Total time less breaks was about 10 hours. I did notice that the more I worked the better my eyes focused, by the end I could actually read the numbers on the tiny resistors, before I started that was a challenge without a 10x. My skills also improve greatly, if I did another I'm confident I could do it in half the time. This was my first SMD. Lots and of fun, I'm glad it's finished though I'm pretty tired at this point.

Thanks for all the help, especially from Chris.

Again I can't say this enough, awesome customer service, and great, I mean GREAT instructions!



LCD Receiver next but that will likely not be for a couple of weeks.
 
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