These are great little tuners and are designed to provide an improved method of matching between a transmitter output, or a receiver input, to an antenna system. In standard guise they cover from 10 to 80m inclusive, and allow resistive loads from 15 ohms to 5,000 ohms to be matched. Reactive components in the antenna system can be markedly reduced and the SWR (standing wave ratio) improved. They handle a maximum of 400 watts PEP on SSB, or 100 watts of fully modulated AM.
There is a modification to fit an extra coil allowing operation on top band, but mine doesn’t have that. I found some pictures of an E-Zee match modified for 160m (Top Band) and have put them into a PDF document here. You will notice the coil wound with enameled copper wire on a grey plastic former; I’m sure you can work out the dimensions from the photo. A switch has been added to the rear of the E-Zee match and the coil is directly across the contacts. The arrangement is inserted into the earthy end of the primary of the 80 to 40m coil, tuned by the dual gang variable capacitor. When the switch is open therefore, extra inductance is added to the primary so the E-Zee match can cover 160m.
Here’s an article by Australian amateur VK6YSF about his KW E-Zee Match which covers pretty much everything you need to know about the standard tuner.
My KW E-Zee Match came as a rather scruffy basket case; it looked as if someone had disassembled it with a view to possibly fitting a top band modification. The rear terminals were cracked with one missing, the internal wiring was missing and the coils lying loose in the case. I also discovered that the previous owner had moved the location of the variable capacitors in the case.
Restoring the tuner to its original state was relatively straight forward. After giving it a clean, the tuning capacitors were put back where they were supposed to be, and the cracked and missing terminals repaired using identical second hand items. It was then a case of fixing the two coils in their correct positions and soldering stiff wire as per the original item, to keep the coils in place.
Thankfully I had the circuit diagram, user sheet and many photos from the internet to help me.
The E-Zee Match is easy to use as there are no switches; coverage is continuous. The only nuisance is having to swap the antenna wires from one side to the other when changing bands. These tuners are often found at radio rallies and swap meets, normally quite cheaply…but do look inside before buying.