TS680.2

                TS140/680 Service Tip

        After replacing finals and/or drivers in the TS140/680
check that all filter relays are operating correctly. Failure
of a band's relays to pick will cause the finals to run into an
open circuit and possibly (probably?) damage them.

        Check the following points for approximately 12 volts.
These diodes are on the filter board next to the final unit.

 Band          Diode           Band          Diode
 1.8            D1             24.0           D6
 3.5            D2             28.0           D6
 7.0            D3             28.5           D6
10.0            D4             29.0           D6
14.0            D4             29.5           D6
18.0            D5             50.0 - 54.0    D7  TS680 only
21.0            D5

        If the problem is in the 1 of 10 decoder chip IC2 on the
signal board (74LS145) unlock problems may also occur.

        Fred Burton .. @ VE3HPL