Omni VII Model 588 Rig / Transmit Shutdown

From the Ten-Tec Omni VII Yahoo! Group - November 30, 2007

The Rig shutdown requiring manual off/on to reset it, only occurs from an over current situation that is deemed to be on the verge of damaging hardware. There is a small amount of hysteresis on the current measurement it is deemed high enough to shut down the rig via the SCR. A spike can do this but only if it exists for a period of time. If the current goes a little above approximately 23/24 amps then there is a white colored HIGH CURRENT string that occurs under the AGC button. It then takes 25+ amps to actually throw the SCR.

The high temperature item occurs when the internal temperature of the rig on the finals gets to around 80 degrees C (176F), which relates to about 70-75 degrees C or greater sustained on the finals heat sink external fins. When this condition occurs, the firmware doesn't shut down the rig, it only disables transmit for a second, then re-measures temperature, and allows transmit if below 80 degrees C. There is hysteresis to prevent cycling if you are hovering at 80. There is NO temperature measurement that would shut down the rig completely requiring hardware off/on to clear it.

Thanks,
73, de KI4JPL
John Henry


November 30, 2007

The rig has a way of being put into transmit via the serial port and also by the Ethernet port.

Serially, the time out is 3 minutes if a subsequent transmit command hasn't been received. Via Ethernet this is 1 minute.

The timeouts are firmware, but in the firmware there are handshakes between two threads and if one fails then transmit will be terminated by the other earlier than the timeouts. One thread is an non-maskable interrupt. So unless the HW is actually failing, the firmware should be able to shut it down now. Unless some unknown bug exists. :-(

73, de KI4JPL
John Henry


QR Code
QR Code 588shutdown (generated for current page)