[Elecraft] Roofing Filter Usage

[Bill W4ZV]

Geoffrey Mackenzie-Kennedy wrote:
> 
> With respect Ron, as far as I know the term "Roofing Filter" was in use
> many 
> years before up-conversion superhet receivers with a fist IF at VHF
> started 
> to appear in the market. 
> 

Correct Geoff.  The first up-conversion ham rigs were introduced in the
early 1980s (TS-930S I believe).  The Japanese manufacturers got the idea
that everyone wanted general coverage in their receivers, which then
required up-conversion and an IF at VHF.  Rob Sherwood had been marketing
his 600 Hz "roofing filter" mod for the down-conversion Drake R4C several
years before that, and as you said the term had already been in use many
years prior.

73,  Bill

-- 
View this message in context: http://elecraft.365791.n2.nabble.com/Roofing-Filter-Usage-tp5682095p5686154.html
Sent from the [K3] mailing list archive at Nabble.com.