I can't remember all but here is one. I went to a VIP who had a Digital phone problem for 6months. They a 30 year old house with a loop run phone system. When they switched from Bell to DTS. The HISU could not sufficiently power the outlets. The phone would ring and then the dial tone would drop out. I rang the phone while my Voltmeter was connected. When ringing the line spiked to 30V for 1sec then then dropped to 10volts. I found the middle of the loop and ran a drop from the HISU straight to that point. The idea was to change the house from a series circuit to a parallel circuit. In parallel circuits voltage stays the same. (thank you high school shop teacher and DeVry). The phones worked great. I made thirty calls to the house before I left to make sure it was permanently fixed.
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