Bulletin:  SK1010
Vendor:    Kantronics
Subject:   KPC-4 power supply

   Kantronics KPC-4 users.. If your TNC fails to receive any data and/or
the receive LED's don't even lite when data and or noise is received,
check your -5 VDC supply.. If you have lost it, replace both C40 and
C41 first. You can use Radio Shacks part number 272-1025. They are both are
10 uf at 35 VDC.

    I was also told from a Kantronics technician that those capacitors
are a problem. They both fail in most KPC-4 about every year.  Since the
KPC-1, KPC-2, KPC-2400, and the KAM are simular in design to the KPC-4
the power supply problem also applies to those models.