KX3 and Si570 tuneing step noise
- Hi all,
I have been thinking of getting a new radio for a long while now. While looking at the options I noticed that the Elecraft KX3 uses the same si570 chip as the main VFO.
While watching videos on Youtube for the KX3 I saw then when you tune the receiver there is no chuging sound as the Si570 tunes in a large step as it does in the Softrock receievrs, how do they do this ? or am I missing something.
----- Original Message -----
Subject: [softrock40] Re: KX3 and Si570 tuneing step noise
> I have built some three standalone SI570 based oscillators and they all suffer from tuning noise, as you claim.
> I have built another one who claimS to have eliminated this noise, but I have not tested it yet. He claims to have adjusted the
> Freeze M DCO:
Please let us know when you have tested this.
And may I remind anyone with a recent Softrock with a Si570 manufactured since the beginning of 2011 that an AVR USB controller with
V 15.15 firmware has the Freeze_M feature. The AVR would need replacing because Tony still uses V 15.12. Fred would be very
interested if this could be tested.
73 Alan G4ZFQ
>> Yes that's what got me thinking, looking at the block diagram of the KX3
>> Hi Fred,
>> which can be downloaded at the address below
>> http://www.elecraft.com/manual/KX3%20Manual%20Block%20Diagram.pdf is
>> It looks almost like a softrock rx from the front end filters to the
>> opamp before the DSP,
>> I have searched for the schematic but no luck so far. If anyone has a
>> KX3 can you please
>> verify that on large tuning steps there is no chuffing . hickups ?
>> > I don't think the Freeze-M bit will remove the hick-up of the
>> > for changing freq. (at TX (fsk) it is mandatory!), it can make the
>> time a
>> > little smaller, maybe.
>> > At the block schema the mixing of the KX3 looks like the softrock,
>> > with the 2m osc signal from the si570. I expect there is no detail
>> > schema available. When using the I&Q outputs on a PC with HDSDR it
>> > maybe easier to see on the screen.