Quote Originally Posted by Paul Hynes View Post
To be fair Andy, you connected everything in the right place. It was your soldering that let you down mainly because of dry joints, but the one that killed the board was a large blob of solder that was on the 9V4 regulator output lead. This was not connected to the board properly and was able to move allowing it to touch the 21v input wire. The regulator actually survived but the input to output short fed 21v to the control circuitry, which caused the damage.

For others considering a little DIY, not just with this project, you need to choose your equipment carefully. A low power soldering iron will not cut it as the tip heat can be depleted quicker than the solder can flow properly on the joint. Not only can this leave you with dry joints, it usually causes some damage to board solder pads and possibly sensitive components due to the time you need to apply the iron for to get the solder to reach melting point, particularly with lead free solder as the melting point is higher than lead solder. I use a 90W temperature controlled soldering station, made by OKI, which is very fast and gives very good joints. Also you need to choose the right iron tip and solder for the job. The solder needs good flux properties and fast melt and flow properties when it reaches the melting point.
Paul,

Your too kind. I think I may well have to buy a super duper soldering iron (wow what an interesting life ). Guys, you've learned from my mistakes. Take Pauls advice, get a decent soldering iron, only do the job if your upto it, and make sure you enough money to fix it if it goes wrong

A