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AKSA's Lender Preamp with 40Vpp Ouput GB

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Hi X,
Here is a pick of how I left it yesterday. I dialed the voltage back to 26V. I used the same setup and changed the DMM to measure amps.

Are you saying to connect the resistor in series with - output and measure A across the resistor, while using a separate DMM connected across the outputs to monitor voltage ?

DCDC.jpg
 
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Hi,
Any other builders that have used the DC-DC-boost care to chime in with a procedure or diagram on how to connect components to test and set the current (if my hookup in #601 is incorrect). I can set the voltage, but the current does not vary throughout the range of the pot. Once I have a proper procedure, I will try a new boost converter, as I have a feeling I may have pooched this one. Thanks
 
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Joined 2012
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Hi X,
Here is a pick of how I left it yesterday. I dialed the voltage back to 26V. I used the same setup and changed the DMM to measure amps.

Are you saying to connect the resistor in series with - output and measure A across the resistor, while using a separate DMM connected across the outputs to monitor voltage ?

View attachment 1239543
Yes. To measure current, DMM must be in the circuit as a series element. Make sure it is in current (amps mode and not mA mode as that might blow the fuse). I have had a couple of these DCDC converters go bad. They are not the most high quality builds but at the price sold, we take our chances.

These 48v output converters are potted and have heatsinking. Maybe they are more reliable? I have not tried but probably will order one to test. Good for 3A.

1701349597181.jpeg


https://a.aliexpress.com/_ms6F2Yk
 
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Thanks X,
I understand that the DMM must be in series with the resistor. The question I have is: " Do I need to attach the positive side of the converter to the resistor like in my picture above, or can the current be set just by having the resistor attached to the negative side of the converter with the DMM across the resistor." This why I asked for a diagram of the hook up for setting the current, so I do not destroy another one. I purchased 4 converters a wile ago.

Also, thanks for the info/link to another variety of converter.
 
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DMM "In Series with" the resistor. Not in parallel with the resistor => Not across the resistor.

Green lead to Black probe of DMM set to 10A (and probes in proper holes) - red probe of DMM to resistor - other side of resistor to blue lead. That is in series.

Just ensuring clarity. You may have done this in a different post / picture.
 
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