[TenTec] Repairs - Omni VII

[Dukes HiFi]

I just completed repair of an Omni VII for a fellow TT user. This radio would lock into TX whenever keyed and required a power cycle to unlock it. Reset process did nothing to help.

I thought I’d share the repair results with the reflector so that others might benefit from my work.

At the outset of my investigation, I convinced myself that the radios was not suffering from some sort of RF feedback that might have caused the thing to lock up. i had seen Orion’s do that so this was my first choice in diagnosis. I did this test by reducing the F power for the TUNE mode to 5 watts. Then I also disconnected the drive to the RF amp to ensure that no significant RF was being produced. The same failure mode occurred, all bands, all modes.

I then studied the operation of the TX/RX control design. This thinking process was led by the possibility that something on the TX DC line might be shorted. This is not possible, however, since every TX command in this radio comes out of a MAX-232 serial port driver. Everything in the radio that would make use of the TX data has its own serial command reading device.

The only thing really left on the table was firmware corruption. Therefore, I went through a rather frustrating process of combining a good 599.RUF firmware file with a working Ten Tec setup program since none of the ones at TenTec.com <http://tentec.com/> work any longer and RKR is gone totally.

What I did was use a legacy version of Pegasus setup software and accessed a known good copy of the 588.RUF firmware.

Viola! All seems working well. Firmware version is now 1.026.

I hope this saves someone out there some grief.

73

Gary

W0DVN