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dford

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This thread is mostly to tell on myself and vent. I've ordered two egg quantum now and can't get either to work. Maybe it is pride but I haven't gotten a hold of Cris for help beyond ordering a new quantum (in which I am about to order ANOTHER)
I used a 30w iron to begin with. Which was wrong. Okay I accept that. I got the second one to work with a teal main status on the test page. Okay...getting somewhere try to get the drogue to the he same place and both go red.
Oh good lord. So I gave it a little time as I did with the Eggfinder (which now works) back to it and I get nothing.
I see everyone on TRF loving the eggtimer line and I want to love it too! Arrgh! I am so pissed off at myself for not getting this the second time!
I bought more low temp solder, 15w iron, solder sucker, wick and a 60x/30x jewelers loop to get the !!#/&×^/;&#£$¥*#,/,,#**=£#* thing to work. And nope. I'm not enjoying the altimeter.
I even went on a family vacation to Utah, bought 4F BP feeling uber confident I'd come back and get it to work.
Nonono. Still doesn't work.

I am about to order a third. Do everything as textbook as I possibly can and get this thing to work. I am determined to make the SMT frickle frackin whatever to work!!!!!

*******#*#,;#&÷**!*~♡\♤●》●◇◇•♧♡●¡!!!!!!!¡¡¡¡¡¡!!!! :mad::mad::mad:

Ahh, I feel slightly better.
 
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Remain calm. Surface mount is not the easiest thing to solder.

Contact Cris, and ask for help.
 
Don't feel to bad, i messed up my first Quark by hooking battery up backwards & fried it upon initial testing!
I use and iron with adjustable heat (Weller WLC100).
Do you have a good magifier with light?
Just takes some patience more than anything!
 
I had trouble with the optoisolators on my Quantum. But a couple of touch ups got the channels to read properly.

I have have a simple weller. 23W, I think. And a variac, usually set between 90-100V. Lit magnifier, no loupe.
 
I have a 15w weller iron, lighted loop, Kesler "245" .020 solder [wouldn't/shouldn't be needed]

Okay. So next go around would anybody say possibly tinning the individual 8 pads per SMT before placement would help? Then just heat the SMT legs until flow?
I'm sure Chris will chime in here eventually, possibly chuckle some at my grievance (I know I would if I were him) but which optoisolator goes to what event? And the rest of the little bitties, which ones go to which so I know if I get a green or teal and one red I know where to troubleshoot?

It would probably be a good idea to literally solder one piece, visually loop troubleshoot like crazy before moving on I'd bet.
I suppose I could suck off solder from all parts minus the wifi and start over. They do after all connect to my phone.
Another thing is I'm using 280mah 7.4 2s lipos. Any problem with that?
 
And who the hell came up with the name optoisolator anyways?
 
Okay. So next go around would anybody say possibly tinning the individual 8 pads per SMT before placement would help? Then just heat the SMT legs until flow?

Disclaimer: I haven't built an Eggtimer and don't know exactly what package you're referring to. I'm gonna take a guess that it's an SOIC. If so, the way I would *always* solder such a device is as follows:
1) put a small blob of solder onto one of the corner *pads* (on the PCB).
2) Hold the chip next to the blob, touch the iron to the blob, and slide the chip into position with tweezers or a dental pick or something. Make sure the chip is aligned on all pads; if not then briefly reflow the solder and adjust it. Actually it's a good idea to reflow that solder joint anyway.
3) Now the chip is held securely in position, it's just a matter of briefly touching the iron to each pin while holding the solder to joint between the pin and the pad (or maybe just to the pad). It should be extremely quick, and you only need a tiny amount of solder for each pin.

If in fact it is not an SOIC but some sort of fine-pitched device, then the calculus changes a bit. I never got really good at dealing with fine pitched devices, although I worked with some folks who were like wizards with them.
 
The optoisolators are SOIC-8's, and that is the textbook procedure as outlined in the assembly guide. You can try tinning all the pads first, but it may not help all that much... the board is already pre-tinned. The key is to make sure that the solder flows from the pads onto the J-leads... don't be afraid to let it wick up the legs a little. If the solder doesn't want to flow, turn up the heat a little bit, and clean you tip often.

I wouldn't make you do fine-pitch devices... anything below .80mm is unsolderable by hand without a lot of practice.
 
I have been following the directions, unfortunately I didn't catch the recommended wattage at first. I have been solder blobbing one corner for placement.
I'm really not mad at anyone. I'm quite disappointed in myself really. I needed to vent it out to people who understand.
Eggtimer electronics are where I will be for a while. I just need to get this solder thing down.
SOIC-8? I'm sure that makes sense to some. I will have to educate myself on all of the inner workings more, eventually. For now i'm focused on getting this working and in the air.
 
For the iron, get a temperature controlled unit. Yes, variacs and such can be used, but that's really old school for people that know how it works. For SMT, temp control is far more important than wattage. It doesn't have to be expensive.

https://hobbyking.com/en_us/soldering-station-with-adjustable-heat-range-us-warehouse.html

Those work fine, hold temp very well, the dial isn't that accurate, but just adjust till you get the range you want. They are a Hako clone, and take the same type of tips. Just one example, there are loads of places to buy them..

https://www.ebay.com/itm/171275813953?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

I like the really fine tip that's bent at a slight angle for SMT work. That's partly because it's what I learned on, so it's nice to have a couple different tips to try. It's worthless for large stuff like 10G wire, that what those other tips are for. :)

The solder included in the kits is good stuff. Use it. If you run out or something, get some like it. I believe it's Kester No-Clean tin/lead. Leaded solder is far easier to use for the inexperienced. Avoid the no-lead stuff. Too much solder is a bad idea. It hides bad joints and encourages bridges. Less is more, particularly with SMT.

Keep in mind what you're trying to do. The idea is to heat both parts, the pad and the lead, equally, and get the solder to flow between them. It wants to do that anyway, so you are mostly putting the heat where it goes. The idea is to get it up to temp fast, hold it there for a second or so, then release. So you want the best possible heat transfer.

It seems counter-intuitive, but leave the tip dirty when you put it down. The old solder will prevent oxidation, which kills heat transfer. When starting a joint, take the iron, clean the tip and put a very small amount of clean solder on the tip. Quickly place that molten solder on the joint where the part is placed. Hold for about 1 second, you can see the solder flow. Remove the iron, holding the part in place for a few seconds. Try not to move the part or board for that cool down, or you get a cold joint. Then put the iron down and inspect the joint, preferably with magnification. It should be shiny and smooth. If it looks grainy, you might need to touch it up.

I like the wire sponge type cleaners over the wet sponge. Both work, but the wire type seem to do a better job to me.

For new tips, or for storage, it's nice to use tinning compound on the tip. It helps clean it up and get it ready for use, after cleaning, or for storage. Again, don't clean it off when storing.

To start out, clean the tip right before every joint. As you get more experience, you learn to tell when it needs it and can do a few between cleanings.

If you have wifi working, but one or both channels don't work, the optoisolators are the place to look. They can be deceptive. btw... Optical Isolator is where that comes from. They are literally a LED and a photo-transistor in there. It's great way to protect sensitive parts from more "dirty" voltages etc.. A single lead not soldered right will cause continuity or firing to fail. Based on the symptom, I'm sure Chris can tell you which part and pins to focus on most.

Hopefully some of that mess of text is helpful. Got a bit carried away. :D
 
So if I've tinned the tip and the solder only sticks to a certain spot on the tip that would mean the rest of the tip is jacked through oxidation?
That is what I'm getting.
Sadly, on the other quantums I have been fiddling with I've noticed a much easier time to avoid the untinned tip side.

Funny the documentation recommends practicing on a different solder set before eggtimer stuff. I said I was going to but was convinced I could learn easy enough. Oh boy am I learning!:bangpan:
 
If solder won't stick to it, yes, the tip is oxidized. You may be able to save it by lightly sanding it, or using something like the wire sponge or maybe a scotchbrite pad while hot. If you try to sand it, don't go too nuts. Do a little and try again. Another good option is the tip tinning compound. It has a lot of flux in it, sometimes that's enough to clean tips off.

A Quantum wouldn't be my first choice to teach soldering on, but it's one of the best for SMT learning, so you're not too bad off. :)
 
Sorry about your travails. The most important thing about these kits is to heed the
intructions. Myself, I built a few electronics kits and a ham radio amplifier that
"was on the edge" but worked. My first surface mount stuff was a Robert Galejs
MAD unit from Aerocon. Built a couple of those with great difficulty but acquired what was
needed to do the job for the EggFinder SMT stuff.

You only need a 15 watt "smallest tip you can find" soldering pencil,
good lighting, head magnification, splinter forceps which in layman's
terms are a fine tipped tweezers and I use a clear, square pyrex
cake pan to assemble the EF projects in. If you flip a component you
can usually find it in the pan.

Out of 6 EggTimers, 8 or 9 EggFinders, two LCDs 4 Rf switches, 2 WiFi
switches, 4 Quarks, 3 TRS's and 4 Quantums, I managed to dork one Quantum
during the building process. Probably solder got under the WiFi module and
I didn't want to mess with it. Swapped out a regulator and it was still dorked
so I chalked it up to "experience".

Hope you can troubleshoot your trouble to your satisfaction.

Kurt
 
I'm also going to open with a disclaimer that I've not got/built a Quantum, but I have build an ET WiFi switch and assembled hundreds (no exaggeration) of boards of similar complexity. As has been said above, SMT assembly work goes much easier with practice but the component sizes that ET uses are definitely within the realm of what a first-timer can handle.

I'll share some things that I've learned about assembling boards like this. Like with everything in this hobby this isn't the only way to get to the "end game" but it does work for me. Have a read, think about what makes sense to you, try it out and keep asking questions to fill in the blanks.

Some basics:
1.) Don't use a 40W iron, the 15W iron is what you want for this job.
2.) If your tip is oxidized, which it sounds like it is, clean it with a damp sponge, never with sandpaper. Soldering iron tips are typically plated with an a oxide resistant layer, which sanding will go through quickly. Once the plated layer on the tip is gone the rest of the tip will erode away from the heat and oxidation. Tips also last longer if you keep a good "blob" of solder on them when they're sitting in the stand between uses. (Wipe this away with the sponge before you go to solder a joint.)
3.) The type of iron tip you want is a personal choice, but I'd recommend staying away from round and sharply pointed tips. My preference for this kind of work is a fine, flat chisel tip with or without rounded corners. One of the enablers to successful soldering is your ability to get heat from the iron into the leads and molten solder - this requires surface area on the tip of the iron which pointed tips do not have. As ttabbal said above "The idea is to heat both parts, the pad and the lead, equally, and get the solder to flow between them." I do most of my work like this with a tip that's about the size of the SMT resistor pads that are used on the Quantum. (Photo here shows my tip of choice for this kind of work on top of an ET WiFi Switch for size comparison.)
DSCN3650.jpg
4.) Leaded solder (ie. Kester 245) and flux are your best friends for this kind of work. Leaded solder melts at a lower temp then lead-free solder so it's easier to get the heat that you need from the iron into the joint/parts. When you heat the solder with the iron the outermost layer will immediately begin to oxidize, and so too will the pads and leads that your trying to solder, and all of this inhibits the solder from flowing into a nice joint. Flux will clean those oxides away. "Rosin core solder" has some in it already, but I prefer to be able to add more to help clean up joints. You can get flux in many forms, I prefer this one. It's messy, it's sticky, it's awful stuff, but it really makes a difference for jobs like this, and when you're done it cleans away with alcohol and a stiff-bristled brush. Don't use plumbing/acid flux on electronic assemblies though, that's asking for a future failure.

Now, to put parts to the board:
1.) If you're starting fresh, don't tin all the pads. If you want to do some pre-tinning, pick one pad from each component, leave the rest.
2.) Restrain your board in something so it won't move when you work, you'll need both hands free. (Clamp if you've got one, tape it to your work surface if you don't.)
3.) Work one part at a time, and I generally work from smallest to largest. Pre-tin one pad for the part you're going to install and build up a little bit of solder on that pad. Using a pair of tweezers if you can grab the part, or a stick on top of it if you' can't, hold the part in place as best you can over top of the pads. While doing that re-melt the solder on your tinned pad and let the part settle down flat onto the board. Take the iron away first, wait a few seconds for solder to solidify, then tweezers away second.
4.) Inspect your part to make sure that it's sitting properly on top of all the pads - a little overhang is OK. If you need to adjust the placement you've only got one joint to re-melt. Get in there again with the tweezers to support the part, add heat, adjust the placement, remove heat, remove tweezers. Don't worry if this solder joint isn't "pretty", you'll come back and clean it up later. But your part is now "anchored" to the board in the right place.
5.) If you're installing a large multi-legged part (like an opto) carefully tack the lead in the opposite corner. Inspect again that you're still sitting well enough on all the pads.
6.) Dab on some flux around the leads of your part. Don't worry if "too much" comes out, you're going to clean it away later. Melt a little blob of solder on the tip of your iron, touch it to each of the un-anchored leads by putting the iron into the "corner" that's formed between the component and the pad for larger parts. You can also put the iron down on top of the lead, pressing it in to the pad, for leaded parts like optos. Hold until the molten solder wicks in to the corners between the component and the pad, this usually happens really quickly so you don't need to hold for long. (Disclaimer: I've done my "NASA certified solder training" course and strictly speaking transferring solder like this is improper technique. When working at home just make sure you post-solder inspect to make sure you've got a good shiny solder joint.)
7.) When all the other leads are soldered down go back and clean up the "anchor" joint by adding flux and heat to re-flow the solder. More solder from the iron probably isn't required.
8.) Using alcohol and a short, stiff brush clean away all the flux residue.

Here's the ET WiFi switch and another board of my own design, both assembled with the above techniques.
DSCN3648.jpg

Go forth and assemble!
 
Well since we are all here and i'm telling on myself, i may as well keep on telling on myself. So the first two soldering irons, yes two. I bought one, never tinned the tip, couldn't figure out why the solder wouldn't flow, must be because tips didn't last too long right? So i bought another soldering iron, this time it came with an extra tip. Both 30w irons also. Anyhow same scenario except i melted solder blobs onto my work table then picked them up with tweezers and carefully melted them where they went on the pads. After so long of doing this i had to resort to the other tip because the original became what i know now as oxidized. Same thing happened so I sanded with 80 grit until the tip was nice and shiny again. It was going so well i sanded an ultra fine tip in the tip. By this point I was "finished" and trying to get the Quantum to work properly. To no resolve I ended up doing more research and discovered a properly tinned tip should look like and perform like. SO I bought ANOTHER 15w, jewelers loop and the rest of the stuff to make an easier time to fix what in the world i did wrong. Too bad for me i think the damage was beyond my knowledge of repair. for now.

so now I have two quantums and soon to be three but two I can come back to once i get soldering down a bit more. reguardless the wifi does work on the two and if I can only get a single deployment to work if not two then i've accomplished something with them and not entirely wasted my money.

i am pretty blown away at how clean your board looks compared to mine. you can only imagine. i would post a picture but it is flat out embarrassing. i think i need to get rubbing alcohol and seriously clean it up. probably need to really work on getting the soids off and starting that bit over.

i'm super grateful for all the tips. i'm soaking it up. i'm the kind of guy who is already looking forward to buying more eggtimer stuff even though i haven't' even gotten the Q to work... i really appreciate all the input
 
I'm going to echo the recommendation to get a proper temperature-controlled solder station. Given the amount of electronics you'll be assembling, it seems like a worthwhile investment, and it's really not a lot of money anyway.

You can of course do very good work with cheaper and simpler irons, but a decent station will improve your odds, and I for one find them much more pleasant to work with.
 
I bought a Hakko before putting mine together and used conical tips like Chris recommended. All went well.
 
20161210_090551.jpg20161210_085919.jpg20161210_085935.jpg20161210_085949.jpg20161210_085956.jpg20161210_090115.jpg20161210_090128.jpg20161210_090159.jpg20161210_090542.jpg20161210_085909.jpg

Soldered the new Q last night. I get dead red on both main and drogue. If anyone can point out any obvious flaws I would really appreciate it.
I'll send Cris an email if need be also.

I get the same beep sequence on start up as well... wifi works...
 
I'm not familiar with the quantum, but if it's on the main and drogue, it's probably something past the CPU. Can you check the optoisolators to see if they are getting any voltage? Also try rehitting some of the smaller parts with the iron (no solder) to reflow some of the joints. A few of them look a tad fishy, but it's hard to tell without seeing the board through a magnifier.
 
What are you using to test continuity? I once picked too big a resistor when testing an egg-device.

One corner of each optoisolator looks weak to me.

Im not where I can reach mine to do a visual comparison with your pics. My egg*s have come with white optoisolators that never seem to have the described notch. I always sweat a bit about which is pin 1.
 
I have hit all the joints again and gone through every step with every picture. I've scoped every joint. None are bridged.
Well wait. There is a lone 472 on the bottom side. The pad ran into the three oval shaped pads next to it. If there isnt supposed to be solder between the two, there is. But I would think the pads wouldn't connect if solder weren't suppose the connect... the same with the 10f capacitor

These opsoitolators have the dot and have been placed the same as cris' pictures.
The only thing I'm using to test continuity is the wifi on my phone once I turned the wifi on. I don't have a multimeter handy.

Which leads me to another question I will humble myself to ask.
On circuit boards such as this wouldn't the red status change on my phone with just the terminal blocks screwed in? Or do I have to have something to bridge the block like an igniter?
 
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I picked up a lot about surface mount soldering by watching videos on youtube. There are a bunch out there. Here is one I liked (e.g. good, in focus close ups -etc.)
[video=youtube;wE4BoCNXRXA]https://www.youtube.com/watch?v=wE4BoCNXRXA[/video]
 
On circuit boards such as this wouldn't the red status change on my phone with just the terminal blocks screwed in? Or do I have to have something to bridge the block like an igniter?

Again- not familiar with this board, but you could try bridging each block with a 100 ohm resistor. Shouldn't break anything, and is safer to test than an igniter.
 
I have no idea what your problem might be, and won't even hazard a guess, but just as general feedback I'd say you're using a lot more solder than you need to. The chip resistors in particular look like they have rather large blobs on the each end, and some of the SOIC pins look a bit blobby as well. All you need is enough solder to flow over the pin and into the joint, and then that's it. When there's less of it, it's also easier to inspect joint quality. Just something to keep in mind in your future soldering endeavors.

But as long as nothing's bridged and you've made sure each joint is flowed properly, then too much solder certainly shouldn't stop anything from working.
 
Did you put a jumper across the PTHs for the optional deployment battery?
Looks like you may have a short between the voltage regulator one of your capacitors. You may want to grab a meter and Do a quick check of your caps and resistors too. I had a bad resistor once building these. An open resistor or shorted cap can cause a world of trouble - fortunately these kits come with spares :)
 
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Did you put a jumper across the PTHs for the optional deployment battery?
Looks like you may have a short between the voltage regulator one of your capacitors.

In English that I think a PTH may be I have not soldered over any optional battery stuff
 
I have no idea what your problem might be, and won't even hazard a guess, but just as general feedback I'd say you're using a lot more solder than you need to. The chip resistors in particular look like they have rather large blobs on the each end, and some of the SOIC pins look a bit blobby as well. All you need is enough solder to flow over the pin and into the joint, and then that's it. When there's less of it, it's also easier to inspect joint quality. Just something to keep in mind in your future soldering endeavors.

But as long as nothing's bridged and you've made sure each joint is flowed properly, then too much solder certainly shouldn't stop anything from working.

From what I read larger blobs were too much too, but going back through it to make sure no joints were cold I added more. Originally most of them were tented.
I made sure I saw flow from the tinned pads onto the legs and back through. During this QC process I've been making sure I heat the pad with the legs.

I'm using a 15w iron. I wouldn't think it would heat up too much would it? Wasn't like I stayed on part for a long time...

Also, when I finished I had more solder than I had in the past two builds when I finished so I thought a little more couldn't hurt
 
I have been putting BP 18mm motor igniter in the blocks to bridge the gap. Not always as I wasn't sure if was needed.
But I will always from now on
 
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