Newbee build: PA03 amp (LM4780)

Glad to hear this problem is solved. I saw that a lot of new boards are sold by PA. By reading this thread people will learn from our problems and mistakes and of course from the things we did well. This is the true spirit of a forum like this. I tell you again this little amp will surprise you when you fire it up for the first time. I have it running for a few months now and and am still amazed by it.
 
Glad to hear this problem is solved. I saw that a lot of new boards are sold by PA. By reading this thread people will learn from our problems and mistakes and of course from the things we did well. This is the true spirit of a forum like this. I tell you again this little amp will surprise you when you fire it up for the first time. I have it running for a few months now and and am still amazed by it.
Yes. It's the amp that keeps on giving! :D
 
Thanks Clog, so that is what i did. (thanks for the advice) I made 2 new smaller holes a "somewhat" higher...... but I am really embarrassed to admit that my "somewhat higher" was a little too high. :( . The legs of the regulators barely peeked through the board. Not ideal. So thanks (again!!) for the pm as I am now going to use the initial large m4 holes and set in m3 screws + a tiny nut on the other side. Yes I am so "lucky" to have those holes in between the ribs....... I was sooooo very close to get myself a new heatsink :grumpy:
I think I am not going to post any pictures anymore :eek:
Don't stop posting pictures! That's how we all learn and hopefully by your picture and effort you'll help someone else down the road. :)
 
Please help!!! I finished all the soldering. Fired it up. Nice click coming from the relays and no smoke. So I connected the input and some old speakers. But the speakers only produced static noise. So than I started gently touching things, as (they say) this "static" is often a ground problem. I also removed the screws holding the vregs to the heat-sink (to eliminate possible contact there). At one moment the "amplifier" turned off and on again. But now there is no click coming from the relay anymore. I still hear some reaction on powering-down....and there is little reaction on powering-up. But no click. Fuses are okay. All suggestions are highly appreciated.
 
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I hope this shows something. It proofs one thing: I have a mouse in the house that can make awful holes in a heatsink :D
 

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Yeaaah Plan (and CLOG !!! and the others) thanks for asking.
It is solved !!!!!!!
But this is something you need to hear. It is so stupid, that it is funny.

As I said earlier, I experienced bouncing readings...all the time. Sometimes the relay clicked and the next day the board was not reacting at all. Sometimes the magic bulb tester was flashing!!! I ended up having contact with Clog by telephone and he walked me through all the different steps and measuring points. We were puzzled by the irregularity of it. Out of frustration (and lack of options) I started touching and pressing items on the board, searching for...... I don't know! This resulted in all kinds of feedback; pink noise and or a even more flashing and/or an intense glowing bulb.

Yes, the board was getting awfully close to the trash can.

But then Clog called me because something struck him. Why was the board reacting this way when it was touched certain places? So he asked me about the foam I was using underneath the circuit board. YES.... STUPID ME..... All this time I was using several foam blocks MAUSER uses for shipping a IC. All the time I was using these blocks to "protect" the other side of the circuit board. To protect the soldering points I was so proud of....
The moment I removed the blocks, the room got filled with MUSIC!!! YES!

Maybe this experience can be of some help for someone else...or maybe I am the only stupid guy that has done this.

But then there is this other thought: what would have happened if CLOG did not find this cause. Then I would have trashed this board and started a second build!!!!!!! I can picture myself sitting at my desk unpacking the second MAUSER box and....... looking for a purpose for these nice foam blocks.... :eek:
 
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Thanks plan and loafimus. I am curious about this first one amplifier by lazy cat. Redjr finished one recently and he was/is impressed by it. I know it is more like putting together 2 already finished products..... so it not so very diy-audio. But the result should be awesome. What do you guys think?

I know that I am going a little off topic but I am pretty sure that Clog does not mind. As he is also always looking for the next improvement and this is the place where people meet that knows what the really nice pa03 can accomplish and what to do to top it.
 
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