Hi John, I don't have a digital camera of my own, but can easily borrow one and send you a picture. They are heavy. About 70lbs. They use no filtering. They are high quality, audio power amplifiers, in series with the secondary of a split bobbin, shielded power transformer. The transformer is responsible for most of the weight. The amplifier can make about 70 volt ac, and is connected in series with about an 80 volt winding of the transformer. They use an oscillator, that is PLL locked to the line, and the output of this oscillator is the reference to the amplifier. The amplifier will buck or boost, real time, to make the output look just like the input. (the sine wave oscillator) The transformer in these units are beautiful. They have full faraday shielding between primary and secondary, including shielded coax type leads in and out. The line is completely isolated from the load. The unit is configurable to allow full isolation including it's own floating neutral. These units are beautifully built, and were well over $1000 when they were new 25yrs ago, but they can be found today for about $35 on the used market.
The only thing I did before using them in the shack, was to install 20amp EMI filters on the input and output. This is to keep rf out of the unit. I run legal limit from time to time and didn't want rf getting in and causing it to misbehave. Although I have not tried running them without the filters. The units may work just fine without them. I mounted the input filter directly on the rear apron. I cut the power cord and ran it through the filter first. The output filter is identical to the input filter. I have a short power cord (about 8") plugged into the back of the line conditioner, and the filters output is connected to a power strip where I have all my radio gear plugged in. I'll send you a picture as soon as I can John. They are distinctive looking enough to spot them from a distance at a flea market. They are a great asset to any shack. 73, Ed AA8TV
