2020 Goals - Soldering an Eggfinder

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It looks pretty good to me. Note the solder "bubbles" on many of the 0402 parts... that's because they're using the standard SMT pad footprint which is designed for reflow soldering in an oven. Most of the SMT pads on Eggtimer's boards have an extra .025" or so added to the end of the standard SMT pads, to allow the solder to flow out past the leads on the component. It's easier for hand soldering than the standard pad footprint.
Assuming you mean the 0603 parts, because I didn’t touch the 0402 components and the 0603 look “bubbly”. They’re supposed to look a little more concave, right? I was thinking it was because I put too much solder on. Does that mean the joints aren’t good? Because I tested the circuit and got good connections along the whole column of components.
 
No, the joints are probably fine. It's just that it's almost impossible with wire solder NOT to get those bubbles on top of the components... there's not much room for the solder to go underneath the component where the pads are located, so any excess bubbles to the top. This doesn't happen as much if the pads are made oversized.
 
Just finished soldering up an Eggfinder Proton. Nice layout, love the oversized pads, went together in a couple of hours. The ESP8266 mounting is a bit fiddly though; I didn't have any 2mm header strips or I would have tried one of those instead of using the supplied resistor leads.

Tomorrow, I'll try powering it up and see what happens.

Thanks, Chris.
 
I thought about including 2mm headers for the Proton, but it's actually better to use the leads for a couple of reasons. First, there's more room for a bit of misalignment... the headers have to be dead-on or they won't fit. Second, and more important, the headers would have to be soldered to the top of the pads on the ESP8266, next to the metal ground can. With the leads, you can solder it to the bottom of the module, and eliminate the possibility of shorting a pad to the can. I've seen a number of the WiFi products with this particular issue... if you solder it per the instructions it can't happen.
 
Arrived yesterday.E3BC5D60-B86E-4C06-835C-068C66DC35E7.jpegI’m pretty excited. I’ll probably build the Tx this weekend at the makerspace. I ordered a LiPo battery, but it won’t be here until next week.

So, dumb question #2 - and I preface this by saying my electronics knowledge is terrible. It was by far my worst class in college (all I remember is V=IR and P=IV). So I recognize this is probably stupid. But, can I use one of the power supplies at the makerspace to test the Tx when I’m done? I think I would just need to set it to 7.4V. I won’t destroy the board doing this, right?
 
Arrived yesterday.View attachment 404439I’m pretty excited. I’ll probably build the Tx this weekend at the makerspace. I ordered a LiPo battery, but it won’t be here until next week.

So, dumb question #2 - and I preface this by saying my electronics knowledge is terrible. It was by far my worst class in college (all I remember is V=IR and P=IV). So I recognize this is probably stupid. But, can I use one of the power supplies at the makerspace to test the Tx when I’m done? I think I would just need to set it to 7.4V. I won’t destroy the board doing this, right?
No such thing as a dumb question! You shouldn't damage your board. Be sure to setup the power supply PRIOR to connecting your Eggfinder TX. Set the voltage at 7.4V as you said, and IF the power supply has a current limit you may want to consider setting it to a "safe" value of 0.5A or so (I seem to recall the TX normally consumes around 100 mA). Turn off the power supply, connect your Eggfinder TX, and turn on the power supply.

If you happen to have access to a 3D printer, I printed the box for my receiver / GPS module. I don't have a photo handy, but could post one later if you're interested in doing this. I'd be happy to send you the files for it.
 
Thanks! The supply does have a current limit. According to the manual, the Tx draws 70mA on average. I’ll set the current as well.

The makerspace has a couple of 3D printers, but I’ve never used one before. I was planning on taking the basics class. I would love to take a look at what you have.
 
Thanks! The supply does have a current limit. According to the manual, the Tx draws 70mA on average. I’ll set the current as well.

The makerspace has a couple of 3D printers, but I’ve never used one before. I was planning on taking the basics class. I would love to take a look at what you have.
Here are some captures of the design from Fusion 360 - I'll try to remember to post photos of the real thing tonight when I get home from work:

Front-side of the case lid:
Eggfinder Case Lid v3.png

Back-side of the case lid:
Eggfinder Case Lid v3 - Back.png

Bottom part of the case. I printed a smaller (0.35" diameter) hole in the side since I was able to accurately locate the antenna connector. I also used plastic threaded inserts in the four corners of the base and used machine screws in the lid. There's also the opening in the bottom which is not shown that allows for access to the switch on the battery box.
Eggfinder Case Base Rev B v3.png
 
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Thanks! The supply does have a current limit. According to the manual, the Tx draws 70mA on average. I’ll set the current as well.

The makerspace has a couple of 3D printers, but I’ve never used one before. I was planning on taking the basics class. I would love to take a look at what you have.

Here's the top view. Note that I printed a hole for the switch. The switch I used is this one.

IMG_3692.jpg

Antenna mounting hole (hidden by antenna).

IMG_3693.jpg

Bottom access hole for battery power switch.

IMG_3694.jpg
 
STL files? Pretty please?
Of course! Happy to make any mods if this doesn't fit your needs. I generated the Fusion 360 files, but it seems they aren't an allowed file type. Happy to send those to you as well if you want them.

BTW, I am also a fan of "The Prisoner". :)
 

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Of course! Happy to make any mods if this doesn't fit your needs. I generated the Fusion 360 files, but it seems they aren't an allowed file type. Happy to send those to you as well if you want them.

BTW, I am also a fan of "The Prisoner". :)
Thank you, kind sophont! (It's a Traveller RPG reference.)
 
Thanks! The supply does have a current limit. According to the manual, the Tx draws 70mA on average. I’ll set the current as well.

The makerspace has a couple of 3D printers, but I’ve never used one before. I was planning on taking the basics class. I would love to take a look at what you have.

I guess the most common mistake is connecting the +/- leads the wrong around, as it seems you are already aware of getting the voltage and current limits setup beforehand. Make sure you know the pinouts, and that you have + to + and - to -.
 
I guess the most common mistake is connecting the +/- leads the wrong around, as it seems you are already aware of getting the voltage and current limits setup beforehand. Make sure you know the pinouts, and that you have + to + and - to -.
ALWAYS good advice to confirm and reconfirm polarity before turning on the power supply. On Cris' Quantum and Eggfinder TX, he has a rectifier circuit that eliminates the problem of wrong polarity damaging the semiconductors. The design will work either way it is hooked-up. Clever guy he is!
 
I guess the most common mistake is connecting the +/- leads the wrong around, as it seems you are already aware of getting the voltage and current limits setup beforehand. Make sure you know the pinouts, and that you have + to + and - to -.

Yep. Thanks. One of the things I did know. :D
But like G.Pitts said, it’s not necessary on the Tx. It works either way you hook the power.
 
Here's the top view. Note that I printed a hole for the switch. The switch I used is this one.

View attachment 404523

Antenna mounting hole (hidden by antenna).

View attachment 404524

Bottom access hole for battery power switch.

View attachment 404525
Thanks. I just have the stick antenna that comes with the kit. I didn’t spring for the more powerful one. Will I need a smaller antenna hole?

Also, I was thinking about putting a switch in for the backlight. Still haven’t decided, though. I’ll probably do very few night launches. Does yours have a hole for the backlight switch?
 
Thanks. I just have the stick antenna that comes with the kit. I didn’t spring for the more powerful one. Will I need a smaller antenna hole?

Also, I was thinking about putting a switch in for the backlight. Still haven’t decided, though. I’ll probably do very few night launches. Does yours have a hole for the backlight switch?
The hole in the case should work fine for the "stick" antenna. I didn't place a hole for a backlight switch, but it would be easy to do so if you wanted it. I'd just need to know the hole diameter / geometry and approximate location you'd want it.
 
Thanks. I just have the stick antenna that comes with the kit. I didn’t spring for the more powerful one. Will I need a smaller antenna hole?

Also, I was thinking about putting a switch in for the backlight. Still haven’t decided, though. I’ll probably do very few night launches. Does yours have a hole for the backlight switch?
I have a (couple of 'em actually) antenna you can have for whatever shipping would be. I'll never use the damn things, I know from experience that the weak link is the SMA connector on the board. Probably get away with a standard business size envelope and a Forever stamp? If so, consider it free.
 
I just finished up my Eggfinder RX and TX Mini. Both powered up first time, and I've got GPS positions getting displayed on my phone. Now I just have to finish my rocket so I have something to put them (and the Proton) into.

Thanks, Chris, for making these available.
 
Thanks. I just have the stick antenna that comes with the kit. I didn’t spring for the more powerful one. Will I need a smaller antenna hole?

Also, I was thinking about putting a switch in for the backlight. Still haven’t decided, though. I’ll probably do very few night launches. Does yours have a hole for the backlight switch?
Be aware that the backlight takes an insane amount of power... like 300 mA. If you're going to use it, get a 2S LiPo pack (you'll kill the 4xAA's real quick), preferably 1200 mAH or more. I have used it on night launches... although it's generally not needed, since you can hopefully see the lights on the rocket after it lands.
 
Man, I’ve had a busy week. But I finished the Tx last night. And. It. Works! 1F3128AA-2B09-4A7D-834F-11D516155305.jpeg I’d send a video, but I can’t do it straight from my phone. So here’s a picture of the RF module light that shows its transmitting, and the LED lighted up which tells me the GPS module has a fix. Sweet!

I honestly didn’t think I was going to be able to do it. The GPS module proved to be very difficult in the corner with three pads. For some reason, I kept making bridges and it took awhile to get it all fixed. The first time I powered it up, it didn’t work. The GPS led was blinking very fast and dim. So I reheated some spots that I thought looked bad, fought again with that corner and bridges and finally it worked.

Again, I don’t think I did a great job on the joints. My digital camera needs charging, otherwise I’d include some close up pics of my soldering for critique. Maybe later.

I got a 2S 300mah battery. With a full charge, it’s run 2 hours so far.

Next week, I’ll probably start the lcd box and receiver.
 
The hole in the case should work fine for the "stick" antenna. I didn't place a hole for a backlight switch, but it would be easy to do so if you wanted it. I'd just need to know the hole diameter / geometry and approximate location you'd want it.
Won’t be necessary. Cris’s post down below plus the unlikelihood that I’ll ever need it has convinced me not to bother with it. Thanks.
 
I have a (couple of 'em actually) antenna you can have for whatever shipping would be. I'll never use the damn things, I know from experience that the weak link is the SMA connector on the board. Probably get away with a standard business size envelope and a Forever stamp? If so, consider it free.
Didn’t see this until too late for the Tx. I hadn’t really considered one, because the user manual suggests I wouldn’t need one for what I plan to use the tracker for. I’ll definitely use it on the receiver box if you’re not going to. But if someone else actually has a need for it, I’d rather it go to them.
 
Be aware that the backlight takes an insane amount of power... like 300 mA. If you're going to use it, get a 2S LiPo pack (you'll kill the 4xAA's real quick), preferably 1200 mAH or more. I have used it on night launches... although it's generally not needed, since you can hopefully see the lights on the rocket after it lands.
Yeah, you’ve convinced me not to bother. I’ll rarely (if ever) use it. More likely that I’d trigger it by accident and kill the battery.
 
Here's a CAD drawing saved as a PDF of the cut outs & drilling holes for the cover. Print it out at scale and then cut it out to help you mark the places. And for the rectangular cut out for the LCD window, if I could do it again, if you have a scroll saw, drill a hole just big enough in one corner, put a blade through it, & cut the rectangle out.
 

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Good deal. Let me know if you print it, and if so how it worked for you.
So I’m taking an intro to 3D printing class this Saturday at the makerspace. We can bring files to print at the end of class. About how long will it take to print your files?

it’s probably dependent on some factors I haven’t thought about, isn’t it?
 
So I’m taking an intro to 3D printing class this Saturday at the makerspace. We can bring files to print at the end of class. About how long will it take to print your files?

it’s probably dependent on some factors I haven’t thought about, isn’t it?
Like most things in life, the answer is "it depends"... What quality print are you looking for? What printer are you using? Etc. Printing this on my Ultimaker S5 using "Fine" (0.1 mm) resolution, Cura says that the box takes 1 day, 21 hours and 33 minutes, and the lid would take 13 hours and 11 minutes using those same settings. If you are happy with lower resolution, the time will be shorter.
 
Didn’t see this until too late for the Tx. I hadn’t really considered one, because the user manual suggests I wouldn’t need one for what I plan to use the tracker for. I’ll definitely use it on the receiver box if you’re not going to. But if someone else actually has a need for it, I’d rather it go to them.
P.M. me. I'll send one your way.
 
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