View single post by sparks
 Posted: Jun 4th, 2014 03:37 PM
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sparks



Joined: Jan 15th, 2008
Location: New Zealand
Posts: 77
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Ok, youre looking at a scan period of 8 seconds or so (8 sec = 8,000 milliseconds or 0.125Hz). It depends on personal choice how much of the radio snippets you want to hear as it scans past. The rule of thumb is only a small fragment, so the scan has to be quite fast.
That function generator on ebay will produce the waveforms, but unless the unit has dc offset and amplitude controls, the waveform will need to go though some sort of level shifter in order to be compatible with the radio's varicap voltage requirements for scanning the band correctly. Its one of the reasons that kit23 is useful as it can be tweaked to produce the correct amplitude and dc offset depending on the radio in use.