Driven by the quest for an EME QSO, I looked for designs of high gain antennas suitable for a small garden, and then built a "Rope" version of a DK7ZB, 12m (5.8λ), 17 element long yagi, realised using lightweight aluminium tubing and ultra-strong, non-stretch fishing line. Unfortunately I overestimated the space available, and may need to reduce the antenna's length by one element: insufficient tension is causing the elements to sag, but I have no space left to "stretch" the line further. Currently the front of the antenna is on a halyard on the main mast, and the rear is attached to a fencepost.
The antenna is capable of >15dBd gain, and first tests show SWR at 1:1 at 144.000, 1.2:1 around JT44 EME activity (approx. 144.130MHz), rising to 1.5:1 at 144.400MHz. Eventually greater control over QTF and elevation will be achieved, but until I sort out supports, I can't aim at moonset direction. Here's a couple of photos (sorry they're dark, but the antenna has only been up at night so far!):
 
Barely picked out by the camera flash, it's easy to see the "Stairway to Heaven". With no boom, this antenna is almost invisible!
 When not in use, the antenna rolls up into a tidy little bundle (note the driven element detaches to make packing/storing easier), and the whole thing weighs less than 1.1kg (2lb, 3oz). Given a front support with a halyard, and a rear anchor, the antenna can be deployed in a few minutes, perfect for portable or contest work.
The quarter-wave matching section was made from two paralleled lengths of 75R satellite TV coax: "satellite coax" has a foil as well as braided outer, whereas ordinary "TV" coax these days has desperately thin braiding, and consequently awful shielding. The matching section was coiled into a loop as there is no boom to neatly tape it to.
I didn't make any allowances for the driven element length, hence the gap in the centre has added aproximately 4mm to its effective length, dropping the resonant point down from 144.2, to 144.0MHz. If I get really bored I may shorten it to the nominal overall length, but a 1.2:1 match around the favoured operating frequency seems too good to bother fiddling with!
 Here the feedpoint arrangement can be seen. Because high elevation requires a low feedppoint, the next obvious step is to bring the amplifier closer to the antenna, eliminating another 0.5dB of loss in the system.
So far two "windows" are available, by attaching the front of the yagi to the mast, and its rear to the north-west fence post, I have a QTF of approx. 145 degrees at 30-35 degree elevation. A vaguely "moonset" position has also been found, on a heading of 250degrees, although here the elevation isn't ideal yet, and the feedpoint is a little close to the ground, causing some detuning.
First QSO on 144MHz JT44 EME was with S52LM, using 4x17, 1500W and 0.24dB NF, worked using 30W.
A bit of "tidying up" of the antenna's mounting method has resulted in it being easier to handle, and also a little shorter. This gives slightly higher elevation, and a bigger azimuth window, as it allows more tie-down points without losing tension. Here's a daylight view. The presence of the other 2m antenna seems to have little effect, but I still turn it sideways to reduce any coupling.
What big antenna?
 
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