I am often asked, "I want to get a CW (morse code) narrow filter for my Amateur radio. Should I get the 500Hz or the 250/270Hz filter?".

The answer depends on your operating style. If you are a died-in-the-wool contester or DXer, you will definitely want the 250Hz filter. And, you probably aren't even asking this question, hi!

If you are a ragchewer and occasionally like to contest or chase DX, well the choice of a 250Hz or 500Hz filter is a little more difficult. If your favorite bands are 20, 30, 40, 80 or 160 meters, I would pick the 250Hz filter; this will help you pull the weak ones out of crowded or noisy bands. If you only operate 10, 12 or 15 meters, the 500Hz filter is fine.

Me? I definitely prefer the 250 or 270Hz filter! I do both ragchewing and a bit of contesting now and then, and definitely like the "keyhole" effect of the narrowest filter I can get my hands on! The only drawbacks are possible ringing; which I have only heard in one receiver with one particular filter and was able to reduce by properly tuning the IF cans on either side of it, and the possibility of zipping right by a wanted contact because the filter is so narrow, you tune past them between characters! But that can be addressed by using the "fine" tuning setting on your transceiver, if you have it, or tuning very slowly across the band; or by switching to the wider SSB filter and getting used to the din, in order to find your station! So, both drawbacks of the narrow-narrow filter can be overcome on most radios, by a careful alignment of the IF cans and careful tuning by the operator (that'd be you).

Whichever filter you choose, get it! Your CW operation will be much more enjoyable. Some of the filters are a little pricey, especially those for 455kHz IFs. They are worth it, my friend. And if you resell your rig you will get a good portion of your investment back.

Just make sure you get a "not DOA" guarantee from the seller, and install the filter as soon as you can after receiving it. Be sure to follow your owner's manual or the filter installation sheet instructions to the letter. Some rigs have to be "told" the filter is installed before they will select it. Be certain you have enabled this after installation or the filter will not work.

Thanks for reading, GL and DX!

73,

Bill K0ZL