Symmetrical Antenna Current Meter

Some time ago, I noticed that my dipole antenna was no longer performing as well as it had before. The tuner settings had to be changed to obtain a proper SWR, and the received signals seemed slightly weaker, with noticeably more QRM.
After some investigation, I discovered that one of the legs of the 450-ohm Wireman CQ-553 ladder line was no longer connected to the antenna.
The cause turned out to be mechanical. Due to the wind and the constant movement of the feed line, one of the steel conductors had eventually broken. This made me realize that I needed to find a better way of supporting and securing the ladder line to prevent this from happening again.
At the same time, I decided to build a Symmetrical Antenna Current Meter. Such a meter would allow me to monitor the current in both legs of the balanced feed line and, more importantly, give me an indication of whether the antenna system was operating symmetrically.
While searching the internet, I soon came across an article by PA1G (Gert-Jan) describing a design that matched my requirements very well. It was simple to build, easy to use, required only a handful of components, and was suitable for powers up to 200 watts.
It looked like exactly what I was looking for, so I decided to build one myself.

For the two cores, I used T68-2 cores from Amidon. Both cores are wound with 30 turns of 0.5 mm enamelled copper wire. The complete assembly is then slid over a piece of Aircell-7 coaxial cable.
The coaxial cable shield acts as a Faraday shield. This shield is connected by a short wire to the "bottom" of the transformer.
Note that the shield should be grounded at one end only. Later, I read on the website of PA0FRI (Frits) that he recommends leaving the Faraday shield out altogether. This keeps the capacitance to an absolute minimum. I recommend reading his article for the reasoning behind this approach.
I decided to leave the shield in place, however, so the version shown in these photographs still has it fitted.
And because "life is too short for QRP", I did not bother using Schottky diodes. Instead, I simply used BAW62 diodes, which were readily available from my junk box. But 1N4148 diodes work just as well, so there is no need to look for anything special.
This circuit has already been built by many radio amateurs and is gradually becoming something of a classic.