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Collins Mechanical Filters - Ceasing manufacture :(


#1

Hi all,

This could well be sad news for those who appreciate a good narrow-band mechanical filter. Whilst other manufacturers available, how long before they follow suit!

https://www.rockwellcollins.com/Capabilities_and_Markets/More/Rockwell_Collins_Filters.aspx

73,

Mark G0VOF


#2

I assume this is because radio designers have switched to DSP. Many of the more recent Ham radio offerings don’t have filters or even space for optional ones.

Colin


#3

Partly, you still need a roofing filter for most DSP designs mainly for good image rejection from the 1st mixer, however the specification for such are much more basic then the requirements for rear IF filtering. The Chinese have flooded the market with filters for this application. If the filters in the DSP are designed well there is no need to restrict bandwidth further down the signal path, all you do here is reduce the effective control range of the AGC system - something which many commercial manufactures could learn from. If its an I/Q system like the KX3 passive component filtering is sufficient.

As a home-brewer I am very sad that this is happening, just as sad as when Toko stopped making their shield coils. This is inevitable as time progresses.

Jonathan.


#4

No mixers, no narrow filters needed in direct sampling rigs which is where we’re headed.

Barry N1EU


#5

Indeed :wink: But for the moment ADC technology hasn’t quite got there yet to parallel with mixing techniques. You still need anti-aliasing filtering on direct sampling radios which is usually consists of a BPF.

Jonathan


#6

Hmm, I’d better punt for a few more 8x7 type filters then. Buy a slack handful of them now and in 5 years sell for a nice return. Got to be more reliable than shares.