[TenTec] Ten Tec audio filter multiple widths

[Brian]

Sending this again.. I think I used wrong address before.

The venerable Ten-Tec audio CW filter is based on 741 op amps, I believe and has two widths.
The version of this I saw in a QRP Projects book (ARRL) has 4 widths as I remember.  I cannot find that exact book on the shelf right now. In my mind/memory it was distinguished by the larger number of available widths.
The MFJ CWF filters had 3 widths available switchable - 180, 110 and 80 (seems narrow to me) - so it says on the front of the filter box.

This is also outlined on Page 82 of Solid State Design for the Radio Amateur.

This is a version of same, or pretty darn close:
http://www.k4icy.com/cwfilter.htm

I suppose at one time I would have liked more widths.. probably now I would be happy with two and just a way to switch in/out for full or filtered sound.

Brian VE3VAW



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