[Elecraft] P3TX questions

[Alan Bloom]

On 05/15/2015 12:34 PM, Jeff Stai wrote:
> 1. What about digital modes like RTTY and PSK at least? How will they
> display? For these modes determination of good TX quality will be huge.

The P3 screen shows the modulation envelope, so flat-topping of a PSK31 
signal, for example, should be obvious.  RTTY is constant-envelope 
modulation so you shouldn't see any amplitude changes.

> 2. Distance from the sensor. In the FAQ the distance supported is 5'6" but
> longer is hinted as being possible. What are the considerations for a
> longer run (say 20 feet)? For example, bigger conductors, or shielding,
> or...?

I'd say go ahead and try it.  I haven't tested longer cables but I can't 
think of any reason they wouldn't work.  All the input pins on the RJ-45 
have pi-type R-C filter networks.

> 3. Switching sensors. I see that mechanical RJ45 switches are available for
> low prices, what are the considerations for using a switch? Also, is it
> strictly necessary to switch all 8 lines?

I suppose you could just leave the +5V (pin 1) and ground (pin 3) lines 
connected to both sensors all the time, but a mechanical LAN switch 
probably switches all 8 wires anyway so it's a moot point.

> 4. Meter display. This might be my favorite feature to have power/SWR right
> there at the P3, but the meter display to my eye is at least twice as tall
> as it needs to be. For digital contesting especially I live and die by the
> waterfall and hate to give up any real estate. Will the meter display
> height be adjustable? (I'd be happy with just the numbers down in a corner,
> like:

We're still tweaking the design so a shorter meter face is a 
possibility.  You can also gain some display space by turning off the 
function key labels with the LABELS key or changing to a smaller type 
font with the "Font" menu selection.

Alan N1AL