[Elecraft] KX3-2M module will work well for CW and SSB, even as an I.F. for higher-band XVTRs

[Wayne Burdick]

Dave,

Are you using a frequency multiplier *applied to the I.F. signal*? If not, then any drift at the I.F., which in the KX3-2M case will be +/- 10 Hz, will simply be *added* to any drift in the final signal.

What I said was that this amount of drift might not be compatible with narrowband data modes. This would also apply to modes like WSPR, unless there's AFC in the algorithm that's tolerant of minor frequency shift. I haven't tried WSPR myself.

Wayne

On Apr 8, 2014, at 4:23 PM, "Dave" <dave at g0dja.co.uk> wrote:

> So why did a previous reply suggest that it would not be OK for narrowband use?
> 
> Anyone who uses a transverter will know that, as the frequency of the lower frequency used and the transverter frequency used changes then the output/input of the chain will change.
> 
> The multiplication occurs as the chain of frequencies up to where you want to get to multiplies and I really do not expect to have to argue this with RF engineers...
> 
> Dave (G0DJA)
> 
> ----- Original Message ----- From: "Wayne Burdick" <n6kr at elecraft.com>
> To: <KX3 at yahoogroups.com>; "Elecraft Reflector" <elecraft at mailman.qth.net>
> Sent: Tuesday, April 08, 2014 10:37 PM
> Subject: [Elecraft] KX3-2M module will work well for CW and SSB,even as an I.F. for higher-band XVTRs
> 
> 
>> There seems to be some confusion on this point. Once a KX3 has had the extended temperature compensation procedure applied, it will have drift of only about +/- 10 Hz in CW and SSB modes on 2 meters. This is not as good as an oven-controlled oscillator (which there isn't room for, of course), but it should be quite satisfactory for SSB and CW use.
>> 
>> If you use higher-band transverters after the KX3, using 2 meters as an I.F., any drift in external units will add/subtract to the total, not multiply the 2-m drift upwards. (Unless you're using a frequency multiplier -- that's a different story.)
> 
>