[CQ-Contest] seeking 9band bandpass filter unit

Jim Brown k9yc at audiosystemsgroup.com
Tue Jul 21 00:09:29 EDT 2015

On Mon,7/20/2015 3:53 PM, Mike Smith VE9AA wrote:
> I too would like to dabble my toe in the SO2R waters, but not at $2000+ to
> get it here to Canada.

Bob Henderson, 5B4AGN, has designed at least two very nice sets of 
bandpass filters based on W3NQN designs. One set covers the contesting 
bands, and uses a motherboard in an enclosure to house six filters on 
plug-in daughterboards. He puts together kits every year or so. Last I 
looked, cost was on the order of U$450, complete with custom built 
enclosures. Cost varies a bit with country (mostly shipping) and details 
of what options you want. The set includes a band decoder with drivers 
for antenna switching relays.

A year or so ago, Bob designed a new set of filters to also cover the 
WARC bands, primarily for use by DXpeditions. They are on the same 
daughterboards, so are interchangeable with the 6-band enclosures, but 
are primarily used in individual enclosures, one filter per band. The 
9-band set is designed with improved adjacent band rejection as compared 
to the original 6-band filters, and I'm building the improved filters 
for 20, 15, and 10 to replace those in my 6-band sets.

I don't think Bob is doing a 9-band daughterboard and enclosure.

For more info, google TXBPF. In addition to Bob's site, it will find this.


73, Jim K9YC

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