Re: My not-so-supercharged PL-380
Since the original PL-380's were introduced in 2009 the Tecsun company has attempted to increase profits by significantly reducing the DSP chip shielding in all post 2011-models, resulting in the digital whine issue when the display is grasped. Knowing the Tecsun company as I do (I have performed about 25 "Supercharging" transplants on their models), I wouldn't be at all surprised if they reduce component quality even further in an attempt to increase profits. Because of this issue, I have personally stopped doing loopstick transplants on all recent-model Tecsun PL-380's. The only PL-380 models that I will "Supercharge" are the ones that I can confirm were manufactured between 2009 and 2011, with the fully grounded shield surrounding the Si4734 DSP chip. Of course, Tecsun's decision to reduce quality in order to increase profits is personally disappointing to me, especially after the time and effort that I spent to write out the 22-page "Supercharging the Tecsun PL-380" article.
As for your current project, I'm sorry that there are no quick solutions for the digital noise issue. Many recent Ultralight radio models have good internal shielding and no digital whine, such as the CC Skywave models (both the basic and SSB versions), the new Radiwow R-108 and the non-Ultralight XHDATA D-808. Of these four portables the Skywave models would be somewhat of a nightmare for beginners to "Supercharge," but the R-108 is reasonable, and the XHDATA D-808 is fairly easy (with the full procedure posted in another major article at http://www.mediafire.com/file/t2989hg61vbkb5h/Supercharging_the_XHDATA_D_-808-FinalMWLW.doc/file
73, Gary DeBock (in Puyallup, WA, USA)