The conclusion of the matter!

[TerryG]

I have two amp3 boards, four TA2021B chip, and nothing works. Therefore after much soldering, and making matter worse through every effort I have come to some conclusions. First that from now on I am going to start every board by soldering on the chip first using an oven. This should end the needless problem of removing solder from pins, and making things look like a holly mess. Second, I have concluded you have one shot at soldering on a chip to a board, after lifting pads and using small wires to fix and remake the connnections, I feel it is just not worth it to try to resolder new chips on boards.

The upside is that I have eight beautifully wound torroid chokes that I can transfer onto new boards when I get them from Jan. I figure all this soldering has been at the least an education on soldering these things. I am quite stuborn and refuse to give up and move on to another board, until I at least get one working amp3. At $25 a pop it really isn't all that bad, I just figure I am going to continue ordering boards and assemlbing them until I get one to work.

The ego deflating part is that I have assembled so many SMD board in the past and they have all worked, not one has had the problems I am having with these. I don't know if it is because of the double copper thickness or what, but they just don't go like all the others, and all the other surface mount chips I have soldered. The funnest thing is the first amp3 I built it took me two hours to put together, and it worked right off and for several days (on my bench) until I put it in a chassis.

I am itching to get to work on an amp5, but want to at least get this amp3 working with this beautiful chassis I made for it.

Frustrated but not discouraged,

Terry

[ulfb]

I was at the edge of giving up...as described in this link (http://www.41hz.com/Forums/topic.asp...21&whichpage=2), the solutionn was using a solder wick as described here: http://members.lycos.nl/anthonyvh/index.php?page=smd

[ulfb]

I was at the edge of giving up...as described in this link (http://www.41hz.com/Forums/topic.asp...21&whichpage=2), the solutionn was using a solder wick as described here: http://members.lycos.nl/anthonyvh/index.php?page=smd

[ckng]

The recommendation to use at least a 50W (somehow the assembly instructions say 50W min and the web site here says 60W) iron is right. When I first ordered the board, I tried soldering a few of the 0805 caps using my existing Antex 18W soldering iron despite the recommendation (since Ian said some had success with lower power irons ). This 18W has served me well in thru-hole projects as well as a couple of SMT ICs I've soldered for another project but on this one, soldering with it is a pain. I think it's because of the double-weight copper and the extensive ground planes.

I order a Antex TCS230, which is a 50W temperature controlled iron and it sure made things a lot easier. However I do not know what's the correct temperature to set so I've set it around inbetween the 250-450°C range (actually that is the default). That seem to work well.

Regards
CK

[ckng]

The recommendation to use at least a 50W (somehow the assembly instructions say 50W min and the web site here says 60W) iron is right. When I first ordered the board, I tried soldering a few of the 0805 caps using my existing Antex 18W soldering iron despite the recommendation (since Ian said some had success with lower power irons ). This 18W has served me well in thru-hole projects as well as a couple of SMT ICs I've soldered for another project but on this one, soldering with it is a pain. I think it's because of the double-weight copper and the extensive ground planes.

I order a Antex TCS230, which is a 50W temperature controlled iron and it sure made things a lot easier. However I do not know what's the correct temperature to set so I've set it around inbetween the 250-450°C range (actually that is the default). That seem to work well.

Regards
CK

[BWRX]

a good soldering iron with the right tip helps more than you know! i usually have my iron's temperature set around 350ºC.

Terry, you're pretty much right about having one shot at soldering the chip onto the board unless you're very careful while removing the chip or have some nice SMD reflow station. i would not recommend soldering the chip on first. that makes it harder to solder all the parts to the other side of the board because it won't sit flat. i think following the bill of materials (the way Jan suggests) is the best order of assembly.

i've got a few working amp3's and would be willing to sell you one since you seem to be having one heck of a time!

[BWRX]

a good soldering iron with the right tip helps more than you know! i usually have my iron's temperature set around 350ºC.

Terry, you're pretty much right about having one shot at soldering the chip onto the board unless you're very careful while removing the chip or have some nice SMD reflow station. i would not recommend soldering the chip on first. that makes it harder to solder all the parts to the other side of the board because it won't sit flat. i think following the bill of materials (the way Jan suggests) is the best order of assembly.

i've got a few working amp3's and would be willing to sell you one since you seem to be having one heck of a time!

[TerryG]

One method I have seen at removing SMD chips is by using a heat gun to slowly melt the solder, then you can remove them with ease. But I don't have a heat gun, and I think it would be difficult to control the temperature, but if the part is bad does it really matter how hot you get it. I don't know anything about the caps and resistors. How much heat can they take.

Terry