[BC] 10 kHz spacing / 9 kHz Receiver

[WFIFeng@aol.com]

In a message dated 07/03/2006 3:44:39 PM Eastern Daylight Time, 
SBailey at nespower.com writes:

>    Have you seen any decent AM radios at Wal-Mart that has decent
>  bandwidth on AM?  I need a monitor for the home stereo and I thought
>  there may be one they have that has half-way decent bandwidth, and
>  doesn't sound like a Delco Car Radio, narrowed down to 4 KC!

The GE Superadio III is very good. (About $50. Radio Shack used to have an 
equivalent. Not sure if they still do.) It is actually *wider* than 10Khz, so at 
night, you're going to hear the 10Khz heterodynes from the moderate-to-strong 
1'st adjacents. (An outboard 10khz notch filter will help.) Lord help you if 
the desired station is running (or is within 20Khz of) an IBUZ signal, though. 

The sensitivity in WIDE mode is reduced, so only signals that are >2mv 
(estimated) are receivable that way. In Narrow mode, the sensitivity is incredible. 
I haven't measured mine against a Field Intensity Meter, but it's gotta go 
down into the 0.0x mv/m range. (Note to self: Next time I have the FIM, do this.)

The other option would be to get ahold of an *older* AM radio (one that uses 
slug-tuned IF cans, *without* ceramic filters) and carefully stagger-tune the 
IF stages. (Generally, less than 1/4 turn to either side of "peak" should be 
enough.) It shouldn't take too much to get a reasonably clean 
bandwidth/sensitivity tradeoff. 

Willie...