Here is where I am at with nRF5_SDK_12.3.0_D7731ad.

Rebuild all target modules:

".\_build\nrf51422_xxac.axf" - 0 Error(s), 0 Warning(s).


Rebuild all target files for soft device:

Rebuild started: Project: ble_app_uart_pca10028_s130
*** Using Compiler 'V5.06 update 6 (build 750)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin'
Rebuild target 'flash_s130_nrf51_2.0.1_softdevice'
compiling main.c...
C:\Keil_v5\ARM\BIN\nrf.h(64): error:  #5: cannot open source input file "nrf51_deprecated.h": No such file or directory
          #include "nrf51_deprecated.h"
..\..\..\main.c: 0 warnings, 1 error
"..\..\..\..\..\..\components\softdevice\s130\hex\s130_nrf51_2.0.1_softdevice.hex" - 1 Error(s), 0 Warning(s).
Target not created.
Build Time Elapsed:  00:00:01


If I use the nRF5_SDK_15.0.0_a53641a, it only supports the nrf52832.
Rebuild all target modules:

	".\_build\nrf52832_xxaa.axf" - 0 Error(s), 0 Warning(s).


Rebuild the soft device:
      	#error "Compiler generates FPU instructions for a device without an FPU (check __FPU_PRESENT)"

Important question, is the nRF5_SDK_15.0.0_a53641a compatable with the nRF51 Development Kit?

At this point the holdup is the Soft Device, it will not compile either with the newly downloaded SDK or with the older version which I was using previously.

Thanks for your support!