[clug] Microwave/Wireless - DTV Overload

[Neil Pickford]

In these days of receivers with almost no RF components it is easier to 
get broadband VHF/UHF tuning by mixing up to a higher IF rather than 
building 3 separate front end RF mixing stages for the various bands and 
mixing down to a low first IF.  These receivers are usually a double 
superhettrodyne and the second IF will be at a more normal frequency.

Analog RF circuits and bits of bent metal cost lots more than integrated 
digital processing.  It's all aimed at saving cents in production cost.

Neil Pickford

Michael Carden wrote:
> On Friday, February 4, 2005, at 06:05 PM, Brad Hards wrote:
> 
>> Huh? If the highest RF is 800MHz, how do you get 1200MHz IF?
>>
> 
> Not that it has any real bearing on the topic under discussion, but some 
> receivers *are* designed to have a first IF frequency that's higher than 
> the desired tuned frequency. Not at all likely in this case in my humble 
> opinion, but an interesting permutation of receiver design nonetheless.
> 
> MC - variously a VK3, VK2 and VK1 something in the pre-internet days
>