In situations where the PE can not be installed directly a jumper cord can be used. First try a standard 2 prong extension cord. I don't advise the use of a 3 prong cord because the ground wire will couple to the parallel capacitance inside the cable geometry. If that happens the interaction will create a choke effect and roll off most of the PE's ringing character.
Note: The choke effect is the same reason why we don't recommend ERS or carbon fiber to be used anywhere near the PE or other types of parallel filters.
Some PLC manufactures roll capacitors in ERS, this is considered a big no no, all that does is roll off the natural ringing frequency of the capacitor. It is the ringing frequency that creates the crossover effect to naturally filter out noise in that particular frequency band. The same is true when transformers are wrapped and the phase is shifted by increased magnetic fields. Damping the frequency shifts the operational band of the part. All of these components are designed to work within a certain parameter, changing the frequency renders the part useless for it's original intention. The choke effect creates harmonic notches (peak and dip odd harmonic frequencies) all over the place and it's very difficult to bring the harmonic balance back. Basically once the frequency is shifted it's gone forever, all we can do is install tweaks as a band-aid and hope for the best. The PE can help by removing the stray inductance created by these magnetic products. As soon as the choke effect/inductance is removed the attached component will respond more efficiently. The amount of PE's required will depend on the level of damage that has been done to the odd harmonic frequencies. Start with one PE plugged into the back of the BPT, wait several days and add the second filter in the next duplex over, wait several days again and add the third, and so on. Don't rush this part because you are trying to find the proper balance of parallel capacitance vs. inductance on the output. We have been known at times to have up to 15 PE's installed on the balanced output, but most of them are wired into the component power supply. After 9 on the balanced output we discovered a special y-cap was needed because we tipped the balance of capacitance vs. inductance too much. Alan configured 3 PE filters to create a matching y-cap. This did the trick and it was the best sound the NBT transformer ever produced. If anyone ever finds themselves installing too many on the output let us know and we'll put together a y-version for your set up. We try to avoid running inductance to earth, but some applications require more filtering than others.
