[TenTec] Wide roofing filter for the RX-366?

[Barry N1EU]

On Thu, May 1, 2014 at 9:38 PM, Bob McGraw - K4TAX <RMcGraw at blomand.net>wrote:

> Otherwise, if you live in an area 5 to 10 miles from town and the nearest
> ham does not operate on the same band the same time as you, then they
> aren't necessary but, certainly nice to have available.
>
>
As far as their minimal necessity - you need at least one roofing filter
installed to hear anything.  And any signal wider than your widest roofing
filter will be attenuated outside the passband.  So at minimum, install a
single roofing filter as wide as the widest signal(s) you want to listen to.

Hardware AGC kicks in by any signal on the band that is over ~ s9 +25dB, to
protect the DAC dynamic range.  Roofing filters prevent AGC riding by such
a strong signal outside the passband.  Signals of that strength are not
uncommon here on the east coast on the low bands, especially during
contests - also on 20M from European powerhouse contest stations.  So
serious contesters and low band dx'ers DO need roofing filters.

73, Barry N1EU