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I recently purchased an SRF-59 and I would like to perform the modifications shown by Dr. Xin Feng. On his website he lists some of the information but I'm still a little confused by what exactly needs replacing and with which capacitors.


In one section of his page he says:


"To get the full high frequencies, replace the two de-emphasis capacitors (0.022uF in old SRF-49 and 0.015uF in newer SRF-59) with 0.01uf ones (showing as "x" in the photo); To get the full low frequencies, replace the two output capacitors (47uF) with 220uF or higher ones."


Then he states:


"If it is too loud even at the lowest volume, replace the two 3.3K input resistors with 22K ones (showing as 220K in the photo).  This also extends the bass further.  If the 220uF capacitors you can find are too large, you may replace the two 0.1uF capacitors nearby with smaller ones (still 0.1uF) to make more room."



But at the bottom of the page he then says:


"As you can see, it still looks very neat and like the original.  In order to ensure super dynamics and bass, very large capacitors are used, 1000uf vs. 330uf for battery decoupling and 470uf vs. 47uf for outputs, respectively.  Furthermore, correct de-emphasis capacitors, the same surface-mount type as the original, are used to ensure untouched treble.  This modified radio simply offers the best sound and reception possible out of your pocket."


Here is the link to his page:



I'm confused. Any clarification would be greatly appreciated. Thank you!