[Elecraft] K3 Passband/DSP Filter Display Question ?

[Phil Hystad]

Sam,

Thanks a lot for your answer.  It would be nice if this sort of information were 
documented.  If it is then I missed it even though I did a full document search
for the letters FC.

phil


On Jan 31, 2014, at 11:23 AM, Sam Morgan <k5oai.sam at gmail.com> wrote:

> 
> yes FC means Frequency Center
> the astric * before the number indicates the APF shift is in the center
> the .68 sez your center (your cw pitch) set to 680hz
> 
> so if you saw .670 or .690
> there would be no * and your APF center
> would now be 10 hz up .690 or down .670
> 
> some have found the ringing they experienced with APF
> was fixed by shifting the APF center off by maybe 10-20hz
> and using the RIT moved their receive the same amount
> 
> On 1/31/2014 12:48 PM, Phil Hystad wrote:
>> I have had my K3 for four years but rarely make use of the passband
>> tuning features.  Today though I was experimenting with APF and the
>> passband controls and learned that I really do not know what I am
>> doing.
>> 
>> In particular, the VFO B display is a mystery to me during passband
>> tuning and APF SHIFT tuning.  For example, in passband tuning (APF
>> not enabled), the VFO B display says FC and then a number like 0.70
>> or whatever.  What does "FC" mean (I can guess, but that would not be
>> useful) and what is this number.  I scanned all the documents I have
>> and have not found descriptions of the content of the VFO B readout
>> during passband tuning.  I know it has something to do with shifting
>> the frequency of center (I think) so maybe FC means Frequency Center.
>> Also, there is an asterisk in the field, like:  FC  *0.68.  Maybe
>> someone can interpret the meaning of that.
>> 
>> If I knew the definition for passband tuning for the VFO B field
>> content I could probably guess at the meaning of the APF enabled
>> display which is similar such as:  APF  *0.68.
>> 
>> I have found lots of description of passband tuning and that part of
>> the display showing the passband width and position but nothing
>> describing the VFO B contents (not covered in documentation on
>> alternate VFO B displays either).
>> 
>> 73, phil, K7PEH
> 
> 
> -- 
> GB & 73
> K5OAI
> Sam Morgan