I’ve previously made my baluns (4:1 and 1:1) and had great success for portable operation. However, I decided to go the commercial route for a permanent balun (1:1) installed on my new fan dipole installation at home. I figured a) it would at least equal anything I could DIY and b) it would be water & UV proof.
With the plan of adding a linear to run full legal power in 2015, I searched for a balun capable of 400W with ‘plenty in reserve’ to handle high duty modes. Plus, being rated higher I figured the losses would be less.
My search led me to the Comet CBL-1000 (1kW PEP). I think this cost somewhere in the region of £50; for this I was expecting a substantial toroidal ferrite with some large gauge wire windings.
The parcel arrived and seemed a little lightweight. However, the casing looked well built and a circular cavity existed which surely contained the toroid plus windings. Removing from the packaging I then discovered the majority of the weight *was* the packaging. Something was not right.
Now, keep in mind the specs:-
Does this look like a 1kW balun?
Despite my reservations I put it into service. I figure at least I have a waterproof casing with space for a proper toroidal balun when I decide to upgrade. I don’t seem to be suffering from stray RF (a problem I previously had using an end fed random wire) although other radios nearby are still misbehaving when the HF radio TXs. I think this is more down to proximity than RF on the coax.
Reports on 40m seem positive; this is certainly a much more effective antenna than my previous non-resonant end fed random wire.
However, in summary, I question the peak power rating of the CBL-1000 and feel I’ve wasted £50. An old toroid, some heavy gauge copper wire and a waterproof enclosure from Maplins and I’ve had something properly QRO for probably 1/5 of the price. Still, we live and learn.