Re: The Tecsun PL-390: a winner!
Stephen,toggle quoted messageShow quoted text
I think that you are asking a bit much from an ULR. Possbly you are asking for more than some of the best radios ever made can do (especially at your grandparents house). I can get some pretty weak long distance stations at plus or minus 10khz on my Icom R75 with Kiwa mods and quality narrow filters at two IF positions, while using a preselector and a quantum Phaser fed by two 120 foot longwires at 75 degrees from each other to null the pests. Still KDDZ 1690 presents a real challenge at 338.82 mv/m. Unfortunately, you can't put all of that equipment into any kind of pocket I have ever seen :)
The EM fields at your grandparents location are absolutly ridiculous.
Were I there and wanted to DX, I would either give up, or move elsewhere!
I mainly use my SRF 59 for a pocket radio. For $10 it is a pretty amazing little radio. My expectations from it are a bit lower than what you are asking, but it gets anything "local" that I want to listen to just fine and will fit handily in a shirt pocket. It even does some amazing things with DX for what it is. You might try one of them, though the little radio will not perform the kind of miracles that you ask for!
Now, I fully respect and will put my butt on the line to defend, the ability of everyone to have an opinion. But, I really think that yours is just setting you up for major dissapointment. I don't think that any radio has ever been made that fits your expectations. With what I know of receiver design theory and considering the state of the art, I kind of doubt that something of that kind can be muilt.
Good luck in your quest (and I am sincere in writing that). If you ever find that magical beast that you seek, let me know! I want one.
In my opinion, the RSSI should be 15dBu on blank channels no matter how strong locals are, and you should be able to hear distant signals with a S/N up to a few dB higher before the RSSI starts to rise. If the RSSI is higher in a blank channel, or starts rising before the S/N gets to 16-18dB or so, then either there's some source of QRM or QRN near your radio, or you're within FCC 1.1310's 614,000mV/m exposure limit... or so it SHOULD be, in my opinion. :(