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2020 Goals - Soldering an Eggfinder

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Wallace

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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.
Alternatively you can just bang the biggest nozzle they have in there, increase the layer heights/print speed and cut that time WAY down. Larger nozzles tend to make for stronger prints (slicer settings dependent, of course) due to more inter layer surface contact. You're gonna see layer lines either way, they'll just be more pronounced.
 

SecondRow

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Ok, uhhh, well. First the good news....

The tracker and LCD receiver work. I tested them today - they both powered up, and I got a gps reading on the LCD screen which corresponded with my house. Awesome! I am very happy I was able to get it to work. But... I screwed something up.

I still need to do a couple things before everything’s finished. One of them is that I need to solder the GPS module for the LCD receiver so I don’t need my phone to find my rockets. I worked on that this past weekend. I got 3 of the corner pads soldered. When it came time to do the last one I made a bridge with the adjacent pad. I tried to heat up the pad to get the solder to flow back. That didn’t work. Then I tried using a solder sucker - and managed to pull both pads of the board.:(
AC05E3B4-B0CD-40CF-8EED-DED684B59574.jpeg
So what do I do now? Is this fixable with my limited experience? If it matters, I do not have the pads anymore. They are very tiny.

Should I just get another LCD-GPS module board from Cris? This seems like the best solution because the gps module is soldered in only 3 spots, and there are no other parts soldered to the board. I think I’d be able to take it off without any problems.

Guidance needed. HALP!!!
 

John Kemker

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Ok, uhhh, well. First the good news....

The tracker and LCD receiver work. I tested them today - they both powered up, and I got a gps reading on the LCD screen which corresponded with my house. Awesome! I am very happy I was able to get it to work. But... I screwed something up.

I still need to do a couple things before everything’s finished. One of them is that I need to solder the GPS module for the LCD receiver so I don’t need my phone to find my rockets. I worked on that this past weekend. I got 3 of the corner pads soldered. When it came time to do the last one I made a bridge with the adjacent pad. I tried to heat up the pad to get the solder to flow back. That didn’t work. Then I tried using a solder sucker - and managed to pull both pads of the board.:(View attachment 407396 So what do I do now? Is this fixable with my limited experience? If it matters, I do not have the pads anymore. They are very tiny.

Should I just get another LCD-GPS module board from Cris? This seems like the best solution because the gps module is soldered in only 3 spots, and there are no other parts soldered to the board. I think I’d be able to take it off without any problems.

Guidance needed. HALP!!!
Don't fool yourself.

It's a lot harder to unsolder those 3 spots than you think. You're welcome to try, but I'd plan on biting the bullet and buying a new one. They're not that expensive.
 

cerving

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Dang, that's a bad one to mess up... that's the output signal from the GPS. If you have some #32 wire wrap wire and a really good magnifier you might be able to fix it...
 

SecondRow

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Dang, that's a bad one to mess up... that's the output signal from the GPS. If you have some #32 wire wrap wire and a really good magnifier you might be able to fix it...
The makerspace has a magnifier and probably the wire, but I don’t even know how to fix it. I suppose I’ll ask for help there and see what I can find online.
 

SecondRow

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Dang, that's a bad one to mess up... that's the output signal from the GPS. If you have some #32 wire wrap wire and a really good magnifier you might be able to fix it...
So, I watched a bunch of youtube videos to get an idea of the technique involved. Looks like I'll need to scrape away some of the solder mask and run a wire from the trace to the half-moon of the module's pad. But what do I do about the pad on the far right? I don't see any trace. Does it go anywhere? Maybe I don't need to fix that one?
 

cerving

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The one on the right doesn't go anywhere, it's OK to leave it unsoldered.
 

SecondRow

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The one on the right doesn't go anywhere, it's OK to leave it unsoldered.
That means I could have left the bridge untouched, doesn’t it? I shouldn’t have tried to fix it. Dammit.
 

g.pitts

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That means I could have left the bridge untouched, doesn’t it? I shouldn’t have tried to fix it. Dammit.
I agree with John Kemker's sentiment above in recommending that you buy a new LCD-GPS kit from Cris (note damage to the pin/pad next to the end pin/pad - looks bad in the photo, but of course we can't see what's left underneath the GPS module). Compromising on the one tool that can help you recover your rocket just doesn't seem like a good idea.
 
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SecondRow

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I agree with John Kemker's sentiment above in recommending that you buy a new LCD-GPS kit from Cris (note damage to the pin/pad next to the end pin/pad - looks bad in the photo, but of course we can't see what's left underneath the GPS module). Compromising on the one tool that can help you recover your rocket just doesn't seem like a good idea.
Not even try jumpering a wire from the trace to the module, huh?
 

g.pitts

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Not even try jumpering a wire from the trace to the module, huh?
I suppose you can try, but is the remaining pad on the module that is visible in the photo still electrically connected to the pad underneath the module? I’m assuming you’d want to tack your wire there. There’s not much left of it as best I can see from the photo. I suppose the question is whether you feel the piece of mind of another module is worth $40.
 

SecondRow

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I suppose you can try, but is the remaining pad on the module that is visible in the photo still electrically connected to the pad underneath the module? I’m assuming you’d want to tack your wire there. There’s not much left of it as best I can see from the photo. I suppose the question is whether you feel the piece of mind of another module is worth $40.
I guess I thought I’d just have to connect the trace to the module’s pad, not to the pad underneath (if there’s even anything there - I’ll have to get a better pic up later).

Maybe this can be practice. I’ll try and fix it. The good thing is that the module is on a separate board from the receiver. If it doesn’t work, then I’ll order a new one. That shouldn’t be a problem, right?

I’m not trying to be cheap here, I swear. It’s more that I messed it up, so I want to fix it. Or at least try to. This whole project has been to learn how to solder.
 

SecondRow

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I tried to fix it tonight. It was messy. It's pretty ugly. But I got continuity between the GPS module pad and the board's GPS output pad. So I finished up the rest and hooked it up to see what would happen.

I turned the receiver on and got the "Waiting for GPS Module" screen, which tells me the GPS module was detected. So far, so good. Then, the LED on the GPS module started blinking, which means the module got a fix. Awesome. But the LCD screen never changed from "Waiting for GPS Module" to "GPS Fix". I left it on for about 15 minutes. The light on the module board kept blinking, but the "GPS Fix" screen never came up. Have to tell you, for about 10 seconds after the light started blinking, I got excited thinking I had fixed it.
 

tOD

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I tried to fix it tonight. It was messy. It's pretty ugly. But I got continuity between the GPS module pad and the board's GPS output pad. So I finished up the rest and hooked it up to see what would happen.

I turned the receiver on and got the "Waiting for GPS Module" screen, which tells me the GPS module was detected. So far, so good. Then, the LED on the GPS module started blinking, which means the module got a fix. Awesome. But the LCD screen never changed from "Waiting for GPS Module" to "GPS Fix". I left it on for about 15 minutes. The light on the module board kept blinking, but the "GPS Fix" screen never came up. Have to tell you, for about 10 seconds after the light started blinking, I got excited thinking I had fixed it.
You may not have waited long enough. Mine sometimes take quite awhile to get a fix.
 

John Kemker

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I'm having a similar, though not exactly, problem.

Red LED comes on. TRS and LCD sync on 433MHz. Amber LED never comes on, even when I take it outside.
 

SecondRow

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I was outside. But I will try again and wait longer.
 

NateB

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I'm having a similar, though not exactly, problem.

Red LED comes on. TRS and LCD sync on 433MHz. Amber LED never comes on, even when I take it outside.
I developed this problem with my Eggfinder Mini. It worked with the amber LED the first time, but after I reprogrammed the frequency the amber LED does not come on. It still gets a fix and syncs with the LCD Rx. It also appears to be reporting the location correctly. I had some difficulties with assembly and being distracted by someone when I was working on it. I cannot rule out damaging the board or any components.
 

cerving

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Both the Mini and the LCD-GPS take awhile to get a sync due to the small size of the circuit board. It's a less-than-optimal ground plane for the antenna. Once you get it though, it's fine... I've flown Mini's to nearly 15K, and I know people who have flown them over 25K.

If you take it outside to a baseball field or somewhere else where there aren't trees and houses blocking your view of the horizon, you should get a fix soon enough.
 

SecondRow

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Both the Mini and the LCD-GPS take awhile to get a sync due to the small size of the circuit board. It's a less-than-optimal ground plane for the antenna. Once you get it though, it's fine... I've flown Mini's to nearly 15K, and I know people who have flown them over 25K.

If you take it outside to a baseball field or somewhere else where there aren't trees and houses blocking your view of the horizon, you should get a fix soon enough.
Ok. I will try again in a more open area. But doesn’t the fact that I got the amber LED to blink mean I already got a fix? I thought maybe there was a problem with the module sending the message to the receiver that it had the GPS fix.
 

John Kemker

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I'm not getting a fix. LCD/GPS never shows a position of the TRS. TRS never shows amber. I'm stumped.
 

UhClem

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I was outside. But I will try again and wait longer.
Modern all in view GPS receivers require only about 30 seconds to get a fix. Longer times indicate problems. I had to remove the shrink wrap over the antenna on my BeeLine GPS to get a fix in 30 seconds.

Older receivers took longer because they had a limited number of correlators. Which meant that they had to guess at which satellites were in view. Once they found one they could gather the almanac data which would tell them which satellites to look for. But receiving a full almanac took around 15 minutes.

Modern receivers can look for every satellite at once. After finding one it takes only 30 seconds to receive the ephemeris data which gives the precise satellite position. Get that for four satellites and you are off and running.

In looking at GPS receiver data sheets I have noticed that the antenna pins are extremely ESD sensitive. Which means that unless protection is provided the antenna is an accident waiting to happen.
 

John Kemker

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/sigh

I'm now looking at the possibility that I've messed this build up right royally. Does anyone remember who it is that builds EggTimers for people? I may have to resort to that to get a working TRS. Desoldering and resoldering the GPS is not viable.
 

Ralph S.

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I know I recently messed up the GPS portion on the Mini. I was in a rush and thought no prob. I reached out to Cris and was able to purchase a replacement PCB and GPS unit. I don't know how much volume Cris has factored in for folks like me but it is worth a try reaching out to him. Always great service and response time when I do email him. Now if we can only convince certain orgs to change recent rulings on wireless it would be great!.
 

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