Hey GASCo - I cannot answer your questions or comment on your soldering, BUT, you should start populating your board with the smallest components (like resistors) first, then gradually go bigger. Otherwise you might find it difficult to get your soldering iron in between the soldered parts.
Help, my Lender is powerless!
After months of planning, studying the BOM and other builds, collecting parts - I finally finished soldering and connecting everything today!
However, I have a problem. I use a 19V laptop brick to a DC DC step-up converter, set to deliver 48V into the Lender. When the DC step-up is connected to the Lender board it does not want to power up. Could it be the laptop brick that shuts down? I don't know where to start, because I cannot measure or trace anything.
This is my first (of 5) builds that does not work on first power on.
After months of planning, studying the BOM and other builds, collecting parts - I finally finished soldering and connecting everything today!
However, I have a problem. I use a 19V laptop brick to a DC DC step-up converter, set to deliver 48V into the Lender. When the DC step-up is connected to the Lender board it does not want to power up. Could it be the laptop brick that shuts down? I don't know where to start, because I cannot measure or trace anything.
This is my first (of 5) builds that does not work on first power on.
Tried another laptop smps. Tried turning down the DC step-up to 24V. Problem remains.
Have you tried following the diagram with a multimeter? Me knowing nothing would try to do that and maybe identify a point where voltage should be but isn't.
With DC-DC disconnected what is the voltage?
What is the voltage after the cap multiplier with it connected?
Remove the daughter boards so we can see if the power is produced after the cap Mx all the way to the final set of smoothing caps at the base of the daughter board edge connector. It should be about 3.5v to 4.5v less than DC step up.
Sounds like your cap Mx might not be working. If an LED is connected it should slowly come on. If DVM connected after cap Mx it should slowly ramp up to 48v over say 10seconds.
Check your polarity of DC-DC converter to board. I think YOB had a problem where it was not work due to flipped polarity of DC input at the jack (that was the DCA though).
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On post 1 of GB thread, there are two Alerts in bold on the errors. Also, the diode V141 is a normal 1N400x and not a zener or breakdown diode.
I’ve been using my Aksa Lender pre for months with the Zener diode in V141. I didn’t realize there was an error until this past weekend so I swapped it out for UF1N007. I always thought there was a strange turn on behavior, the LED would pulse for about six seconds before it steadily lit. Now, it’s a smooth turn on process
Thanks guys!! Happy to get the encouragement. I looked through the diyA store for boards for an output stage, saw the MoFo then read some great things. I have a pair of Klipsch Forte II's with Crites crossover and Ti dome on the tweeter and this combo seemed almost perfect. There are so many great projects that it's way too easy to get side-tracked......
Phil
Phil
I actually had these corrections already. I just forgot about them and thought had made a mistake when looking at the schematics I downloaded a couple weeks ago.
Not complaining but just suggesting that the Schematics could be updated if possible so to avoid confusion in the future for others. It might be overwhelming to keep all the information you read while researching (not saying that keeping the post 1 update is an easy or fun activity either).
But I digress. I’m excited to hear this puppy soon!
I’m sorry for your basement X! That really sucks!!
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No, will hopefully get around to it tonight. Thank you for all the pointers X. I suspect (and hope) the DC-DC step-up is the problem here. I will bypass it (using a 24V smps currently used for a TPA3116 amp), to check voltages on the motherboard and daughter boards.