On Mon, 07 Jul 2008 06:08:21 +0100, Highland Ham wrote:

The one I had used triple conversion superhet. Mircoprocessor
controlled.
The first IF was like 336Mhz to 10.7Mhz to 455Khz. There was no front
end. just direct conversion to the IF. So all the micro had to do was
control the oscillator from 336Mhz to 900Mhz using up conversion on
the low bands and down conversion on the higher bands. Cell phone band
was locked out. Guess what you can pick cell phone band on the image
frequency back in the day.
========
Are analog cellphones still used in the USA ?
I thought by now it is all digital sigs which can not be received with a
'normal' receiver , so what's the reason to 'lock out' the cellphone
frequencies ?

Frank GM0CSZ / KN6WH

The same government logic that made TV broadcast standards
backwards-compatible for over 50 years.

__
Gregg