30m at the coast.

A very brief opportunity last evening, under continuing Artcic cold, to test the shortened 30m vertical at the coast.

A stiff wind from the Arctic proves the usefulness of a shortened antenna.  WSPR tests at 30m, looking away from the main coast.

The location is good for a quick set-up, not so good for paths other than to the north.  The idea was to firstly see if the design would still exhibit a good match as per my home experiments, and secondly to see how TF4X would hear me.

Well, it wouldn't match up beyond 2.3:1.  I eventually figured out why: the radials were pegged to the ground at the far end using aluminium tent fixings, without even a cord to isolate them from the pegs. 

Despite being on a beach where strong tide currents remove almost every bit of debris daily, I found some (non-conductive) short sticks, attached the radials to those (just ~6cm off the ground), and I instantly saw the required 1.3:1 match.  That's the beauty of portable working: you always learn something new!  You also always end up talking to passers-by (for far too long in cold weather!), who never really quite believe your singal is getting to the other side of the planet!

Slightly noisy, but shows the 1.3:1 match obtained on raising the radials and not using metal pegs!

First, here's how my vertical (red line, MW6PYS) did, compared to my slightly inland half sloper (blue line, MW1CFN).  Both stations used WSPRlite 'Classic' transmitters at 200mW:

These plots are always potentially misleading, as they use a log scale.  It's important to look at the signal strength reports, too.  For my chosen station of TF4X, directly to my north and making full use of the sea in front of the antenna, the difference was very good:

So we can say the antenna format works just fine, provided the radials are held off the ground with non-conductive fixings like a good length of cord to metal pegs, or directly to sticks.  The sea enhancement is also just as strong at 30m as it has proven to be at 20m.  Success all round!