G+_Brian Jones Posted February 23, 2018 Share Posted February 23, 2018 Hi KITAs, (Stupid Question Alert) I'm new to soldering and for want of a better word Electronic-ing, This is how new I am, are there different types of solder for different jobs or is there only one type? Sorry if this sounds stupid. Link to comment Share on other sites More sharing options...
G+_Ant Pruitt Posted February 23, 2018 Share Posted February 23, 2018 yeah there are different types and sizes out there. The one pushed the most is the "lead free" solder. I've stayed away from that and use the 60% leaded solder for working on my drone build. It seems to work much better for me. Link to comment Share on other sites More sharing options...
G+_Ant Pruitt Posted February 23, 2018 Share Posted February 23, 2018 No stupid questions exist other than the one where you ask someone for their password as if they'll give it to you. :) Link to comment Share on other sites More sharing options...
G+_Joe Valasko Posted February 23, 2018 Share Posted February 23, 2018 There are many types and sizes of solder. Acid Core solder should only be used for plumbing. Rosin Core solder is typically used for electrical soldering. The diameter of solder is also something to consider - the larger diameter solders are typically used in making larger solder joints (not typically useful for electronic kit assembly). Here is one article you might find useful. https://www.lifewire.com/types-of-solder-flux-818850 Link to comment Share on other sites More sharing options...
G+_David Alitz Posted February 23, 2018 Share Posted February 23, 2018 Lead free solder is much harder to work with. It just doesn't flow like the lead based. The lead doesn't vaporize; so you aren't breathing lead. Rosin is an important ingredients for cleaning oxidation and making a good connection. The rosin does vaporize and isn't good to breath. Try to work in a well ventilated area. Link to comment Share on other sites More sharing options...
G+_Brian Jones Posted February 23, 2018 Author Share Posted February 23, 2018 Thanks for the tips everybody, I'm mostly just going to be assembling bits from the Elegoo 2560 kit for starters, my ultimate project when I get going is to make my own LED sign using 2 Max7219 8x4 LED arrays (which should work out at 8x64 resolution). Link to comment Share on other sites More sharing options...
G+_Brian Jones Posted February 23, 2018 Author Share Posted February 23, 2018 Forgot to say there I've got choice of a Raspberry Pi 2, 3 or Arduino Mega 2650. I might have to publish it on here as I put it together ?. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted February 23, 2018 Share Posted February 23, 2018 MAX7219 is an 8 digit 7-segment LED driver IC. (7 segment displays have 8 LED's counting the decimal point) So each IC can drive 8x8=64 LED's, using two IC's will give you the capability of driving 128 LED's which is only 2x64. To get 8x64 you'll need 8 MAX7219's, there are much better ways of driving large discrete arrays. A lot of the high cost of MAX7219 driver IC's is the internal decoding so that you can give it BCD values and the IC converts that to the proper segments to light. Link to comment Share on other sites More sharing options...
G+_Brian Jones Posted February 23, 2018 Author Share Posted February 23, 2018 I get where you are coming from for that, as far as I know and I could be wrong, Max7219 can be both the 7 segment plus . or 8x8 pixel displays, the one's I've got are 4 8x8s already stuck together, looking at example code for Arduino it looks like instead of using 1 8x8 grid I can specify however many I'd want to use. 8 in a row seems to be the suggested amount to use max as the Arduino / Raspberry Pi can only power so many linked units although again from what I've read if I use a separate power supply the number of LED grids can be more than that. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted February 23, 2018 Share Posted February 23, 2018 Brian Jones Yep, as I explicitly said, if you use 8 MAX7219's you can have 8x64. It's just not the the lowest cost or most efficient way to do it when you are not driving seven segment displays. Link to comment Share on other sites More sharing options...
G+_Brian Jones Posted February 23, 2018 Author Share Posted February 23, 2018 The ones I got from Amazon were from KWMobile for just short of £10/$13.97 (Approximately) from Amazon (http://amzn.to/2EMoNF4), they do sell others but I think they are different sizes from the ones I'm thinking of using. I'm only doing a basic scroll / clock for now just so I can see how things work, As time goes on I'll probably use one or two of the Adafruit 32x64 panels but for those I WILL need extra power. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted February 23, 2018 Share Posted February 23, 2018 Wow those are a bargain! 4 MAX7219's plus 4 8x8 LED matrixes , PCB and associated resistors & caps for less than $15. Just the 4 MAX7219's alone cost $20 when you buy 1000 pieces. I'm guessing they are using the counterfeit MAX7219's that are found everywhere in China. Link to comment Share on other sites More sharing options...
G+_Brian Jones Posted February 23, 2018 Author Share Posted February 23, 2018 They might well be, I've seen similar matrices 3mm per "Pixel" all the way up to 9mm. The only thing is that (according to Instructables) you have to rotate the characters 90' in code otherwise they come off wrong way round. Link to comment Share on other sites More sharing options...
G+_Paul Hutchinson Posted February 24, 2018 Share Posted February 24, 2018 Just found out that those boards are based on a reference application design by Maxim. The reference design units sell for $50 digikey.com - MAXREFDES99# Maxim Integrated | Development Boards, Kits, Programmers | DigiKey Link to comment Share on other sites More sharing options...
G+_Bob Shields Posted February 25, 2018 Share Posted February 25, 2018 In the Arduino world, there are several libraries available for driving strings of MAX7219 boards. AdaFruit has one, and FastLED is another. It takes some configuring, but you can set it up to handle the string in any orientation (hor, vert, L to R, R to L). You can buy the 8x32 boards for $5 from banggood (w/ 3-4 weeks shipping) or for a few $ more on Amazon. Link to comment Share on other sites More sharing options...
Recommended Posts