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Clifton Labs Z10023A BCB Filter

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Feb 24, 2001
So for some reason, I removed my ICE BCB filter inline with my Perseus SDR. I was experimenting with a couple of filters several months ago and (I guess) I removed all of them to prevent any signal loss. Well that proved to be a bad strategy.

Here's what my HF spectrum looked like with no filter:

You can clearly see the 3-4 Mhz "hash" that is developed due to the MW signals overloading the Perseus SDR.

The broad (40Mhz view) isn't very accurate... here's a zoomed-in 10Mhz view:

Here's a view of my older ICE 402X High Pass Filter:

As you can see from the above, it does "something" although the attenuation isn't steep enough and there's very little insertion loss until about 1.2 Mhz -- the top end of the band is still blasting through.

Here are a couple of pictures of the ICE 402X filter:

After some online searching, I found several BCB filters. Prices were fairly steep. One costs $195 and the other $225 with a 3-week wait.

Andy Ikin of Wellbrook recommended I talk to Jack Smith @ Clifton Labs. After several emails, Jack steered me in the right direction. He also added a BNC female instead of the usual SO-239 connector. This way I can use a short BNC jumper to my Perseus and rid myself of another RF adapter. It's a very clean, professional design.

The Z10023A Elliptical Filter:

...and check out the results:


And zoomed-in at 10 Mhz:

So if you're not hearing any signals in the lower HF frequency range AND you live in a suburban environment where AM BCB signals are very strong then you may want to consider a filter. It could possibly improve your reception.

Clifton Laboratories Home
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Premium Subscriber
Nov 3, 2004
I made one years ago, it looked like a copy of your original one. I had a nearby station with ground issues that was amazingly strong and it cured my problems completely, until they redid their antennas. I guess it's still around here someplace. I could hear everything before I got it, but I could also hear either a pulsing "hash" or the audio from the station in the background all over the dial, in every receiver I had, except for my NRD-515. The station took almost 3 years to fix the problem. At it's worst, i got about an S-9 signal with no antenna of any kind, and just touching anything would peg the meter.
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