[Elecraft] K3 VLF transverter?

[Fred Jensen]

On 11/30/2012 6:50 AM, KD7YZ Bob wrote:
> Howdy K3' people:
>
> I'd like to listen down around and below 100kHz

I use a Palomar VLF converter [0-500Kc --> 3.5-4MHz] coupled to my flag 
pole on the deck with about 9m of insulated wire.  It is receive only 
and actually goes up to about 580Kc before things start to drop off. 
The LORAN-C station in Middletown CA overloaded the front end but 
LORAN-C is gone now and I've occasionally heard a couple of the XSH-xx 
stations.  KSM on 426Kc on Saturdays is usually around S8 during the 
day.  Alas, I don't think the converter is made any more.
>
> Well, and be ready to transmit if they approve us to xmit in the 137kHz
> area  ( I think that's the proposed new band anyway).

135.7-137.8 I think.  I've seen two TX strategies:  One is to divide a 
crystal oscillator [the one I saw used a cheap CB crystal] down to a 
frequency within the 2.1 KHz bandwidth, the other mixed a crystal 
oscillator with a VCXO such that the difference frequency fell in the 
band.  An EFHW antenna is "only" 1.1km long. :-)  2.1KHz would 
accommodate one SSB signal?

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2013 Cal QSO Party 5-6 Oct 2013
- www.cqp.org