Another SMT Soldering Technique

Cary showed me how he likes to do surface mount soldering. Mike uses highly activated liquid flux. Cary prefers a gel flux.

Cary showed me 2 YouTube videos that shows the technique. Someone "borrowed" his smt kit.






I went to Fry's and they had some. It worked like a charm. I tacked the part, put some flux down and it all worked as in the videos.

My problem is that the Fry's stuff does not clean up well. So I need better flux gel.

So, I see myself using the gel for multi-pin parts and the liquid flux for the basic caps and resistors.

To practice, I looked on the net and found 2 companies that sell practice boards. One is Topline. They have a board that has 4 tqfp parts. Depending on how many you purchase, it is $10 - $6.75 per part. Practical Components was even more expensive.

So a browsed ebay and digi-key. What I found was smt converter boards on eBay for $1.80 each. Search Google for "smt converter boards tqfp" to find parts. If I looked further, I could have gotten the same board for $1.50. The board is for a single 80-tqfp chip.

Then I looked on ebay for qhips, all too expensive. I looked on digikey. I found a Pic processor for $2.91 in Quantity 10. Part number PIC18F83J11-I/PT-ND.

So minus shipping and tax, $4.41 per practice component. After the fact, you wind up with a working PIC18 if you do it correctly.

I hope that I will not require the 10 for practice, so some people might be getting some practice boards from me.

Once I get this working, I will be very exited. I will have the confidence to build my AT Sprint 3B1 from Steve Weber. And will order his ver 4 in February when it ships. I also have the NUE-PSK digital Modem It does have one TQFP-64 .5mm pitch part. The rest are easier pitch or 1206 components.

Right now I have friends helping me debug issues with a Small Wonder Lab PSJ31 20M rig. I had 2 resisters I swapped, otherwise I placed all components correctly. No cold joints. I have one part that is bad and another is being sent to me.