The NB6GC / KO6NO Remote Adapter For the Harris RF350K and RT-1446/URC
In 2007, the USS Hornet Amateur Radio Club created a circuit board to match the RS232 mode of the Harris A1A19 Module for use in the radios of the USS Hornet Aircraft Carrier Museum Amateur Radio Station, NB6GC. These Remote Adapters allow Windows software to control all operations of the radio.
The NB6GC / KO6NO Remote Adapter, shown above mounted on the front panel of an RT-1446, is capable of baud rates from 300 to 19,200 baud. The module is completely assembled and comes with the ribbon cable necessary to connect to the radio's Control Board. An Operator's Manual with a schematic diagram is included. Each adapter and cable are tested before shipping.
By 2012, all units of two productions had been sold, a total of 80 adapters. A second organization was allowed to produce units of the same design in return for several of the bare circuit boards. Kits or complete adapters were sold using those boards. By 2019, all available boards had been sold. Due to a recent request for an adapter, we have purchased a small number of assembled units from the second party. These units are now available.
The Hornet Amateur Radio Club also developed software to control the RF350. The program is in use at the HARC Amateur Radio Station, NB6GC, on USS Hornet. Go here to download the NB6GC software.
Upgrading the RT-1446 Firmware
There are at least two versions of the EPROM program for the radio's Control Board . The version may be determined by examining the labels on the three EPROM chips after lowering the front panel. The EPROMs are 28 pin DIPs located in the upper right corner. During the testing of the NB6GC Adapter with NJ7C's software, Dale was able to optimize operation of his program with versions 601C and 604M of the EPROM so that remote control is possible with either version. However, version 601C does not provide adjustment of the receiver RF Gain and also requires a more complicated method for setting the AGC and Mode. Version 604M also includes a feature to allow programming unique Receive and Transmit frequencies in the memory channels for half duplex (split) operation.
Because only one RF350 on USS Hornet had version 604M installed, we set up a facility to create and install version 604M chips. For owners of RF350 or RT-1446/URC units, we can provide EPROMS programmed with Version 604M. Because the contents of the EPROMs are copyrighted material of Harris Radio, we are offering this as a service at a price equivalent to the cost of EPROM chips and shipping. All EPROMs are clearly marked with the original copyright label of Harris Radio.
Thanks to the many purchasers over the last two years, all of the first production units were sold. For anyone interested in creating their own board, we have decided to place the schematic and artwork on line for download. The schematic and pcb files were created by using ExpressSCH and ExpressPCB which are available free from their website.