Thursday, Oct. 11, 2012 — Something old, something new, something borrowed, something homebrewed …. no, no, there’s no wedding plans in my future, just the ongoing romantic nostalgia between me and my BC-348Q receiver.
The “something old” is the BC-348Q; the “something new” is a little goodie I picked up last weekend at the Bowling Green hamfest, a Heathkit HD-1418 active audio filter. I picked up the appropriate cabling for it today at Radio Shack, cobbled together a power supply, and set it up tonight at my listening post in the library.
The seller told me the filter worked perfectly; it looked perfect, too. Having seen what this filter brings on eBay, the hamfest price was right, and near the end of the ‘fest I made him an offer he accepted.
The Heathkit filter roughly approximates the Datong FL-2 that I have owned for years. The filter offers variable bandpass for both SSB and CW reception as well as an excellent manual notch. So how does my “something new” (relatively) play with my “something old”?
The filter works very, very well, and provides the BC-348Q with a degree of selectivity it needs to be a useful receiver on a crowded ham or shortwave band. On SSB, I used the filter to cut down on the adjacent signals from nearby stations. The filter adjustments allow you to really tighten up the bandpass; it makes the receiver much more usable as a result.
On CW, it also made a huge difference. There was some DX operating tonight, and a rather huge pileup as a result. Without the filter, the mass of calling stations created a huge pile up unintelligible signals. The HD-1418 allowed me to slice up the pileup and pull out signals I couldn’t decipher before. The only problems I experienced were signals stacked on top of one another. No audio filter would help with those signals less than 100 Hertz apart.
The Heathkit filter worked wonders on both voice and SSB. I was able to tune into W1AW’s CW signal right alongside a PSK31 signal without hearing the digital signal in the bandpass at all …. quite a feat for such “old technology, hi!
I’ll have more to report later as I put the receiver and filter through its paces. For now its QRT … 73 de KY4Z SK