Было в рассылке, как улучшить работу беренджера. Модификации UMC202HD. Не сообразил куда разместить, оставил тут.
On Wed, Nov 19, 2025 at 05:00 PM, Peter E wrote:
I suspect the UMC202 is the limiting factor here....
Adding a 100uF to 200uF across the AF input coupling capacitors will lower the frequency to about 0.01Hz.
The stock XLR input has 2 47uH capacitors in series with the anodes in common with a bias resistor.
The stock 1/4" TRS input has 2 10uF capacitors in series with the anodes in common with a bias resistor.
There is another 47uF in the signal path from the last opamp to the ADC.
The UMC202 service manual is extremely useful and has the most frightening copyright notice I've ever seen.
If you are braver than me, you can bypass the analog input sections and tie directly to the ADC.
https://modimications.com/umc202hd-mods-2/ If you read down there is a link to a diagram of the UMC202 that will be extremely useful.
I suspect if one is determined enough and willing to risk destroying a UMC202, it could be turned into an instrumentation grade A to D converter.
If you are really brave, this shows one way to bypass the input.
https://www.diyaudio.com/community/attachments/loop-jpg.972419/Note: I have not tried this.
The lowest frequency sinewave I can generate is 0.01Hz with an XR2206, the modified UMC202 might go lower.
