[Elecraft] K3s and DEMI transverter

[Wes]

In all honesty I haven't been on 2-meter EME for 35 years.  Gear was all 
homebrew then.  That said, I would stick with a 28 MHz i-f.  You must consider 
image response and where it lands with respect to other services. I once saw an 
analysis that promoted a different i-f but I fail to remember what it was or 
why.  Definitely avoid anything lower.

I would split everything if you are ever to consider a separate HP amp and 
mast-mounted preamp.  If you are going to worry about frequency stability I 
wouldn't bother with the high stability option.  You can use an external source 
that is much better.  I wouldn't necessarily opt for a GPSDO without knowing its 
phase noise performance, however.  I put together a surplus (ebay) Morion OCXO 
that I've had running for about six months and it has been within 3 milliHz of 
10 MHz for several months.

I would suggest the low drive power input.  You can always attenuate this.  PTT 
low to TX would be my choice.

Wes  N7WS

On 6/2/2021 6:32 AM, W8JH wrote:
> I am looking to add the DEMI (Q5) transverter to my K3s and have no
> experience with transverters other than the internal one in my KX3.  In the
> future, I may wish to progress to 2m EME as well.
>
> Here are some choices I need to make and I would appreciate any advice:
>
> Common IF vs Split IF.  I'm thinking split IF with a K3s?
>
> Common RF or Split RF.  Common RF for one antenna connection?
>
> IF drive level of -20 to 0dBm vs 0dBm to +20dBm.  I think the K3s
> transverter output is 0dBm so I'm not sure what to think here.
>
> PTT polarity low instead of high I'm thinking.
>
> High stability Local Oscillator vs. standard.
>
> I could get a custom IF and I think there is some slight advantage to a
> 14mHz custom but I'm guessing the 28mHz standard IF is good enough?
>
> Thanks in advance for any advice or references.
>
>
>
>
>
> -----
> 73,
>
> Joe, W8JH
>
> K3s, KPA 500, KAT 500 and  KX3 happy user.
> --