USKI-5 Universal Sequencer & Keying Interface
© Copyright 2015 QSK, llc
www.qskllc.com
Page 6
USKI-5 Program (B)
has all the features of Program (A) but in addition has two
separate timing sequences, one for CW and one for PTT operation. Each can be
programmed with different delays if necessary.
USKI-5 Program (C)
provides for sequenced keying of a transmitter (or transceiver),
amplifier, and other accessories from an external (not the radio’s built in keyer) CW
keying device while allowing normal direct non-sequenced PTT or VOX control of the
transmitter. This program is NOT intended for use in stations with transverters, TMAs,
etc. Program (C) also provides a transmit inhibit function. Several station configurations
are suitable for control with Program (C). Probably the most common is shown in figure
3 (the order of connections for outputs 1
– 4 may be different depending on the specific
devices being controlled
FIGURE 3
The CW keying device is connected to J1T. The transceiver’s external amplifier relay
control output is connected to J2T. Closures between J1T and ground will sequence the
outputs of all connected devices and send a closure to the CW input of the transceiver.
When PTT is activated directly into the transceiver, the send output connected to J2T
will cause all other devices to key simultaneously without any delays.
Another application for Program (C) is with stations that use separate components such
as a VFO, transmitter, receiver, and possibly other devices (power amplifier, antenna
T/R switch or relay, etc.) as shown in figure 4.