…as promised. Sorry about not posting it on Monday, but thanks to Patricia for reminding me. This mod will prevent the transmitter bias from being turned on while the firmware is updated. The red LED will still come on, but that isn’t a problem. Also, there’s no reason to do this if your radio is a receiver only.
Install a 10K (approximately, the one I used is a 9.76K because it was within arm’s length) resistor, 1/8 watt preferably (because it’s small, no significant power will be dissipated) on the top side of the transmitter board a shown in the photo:

Obviously, I’m not calling it the “top” side because it’s the component side. It’s the side that faces up when the transmitter board is installed on top of the receiver.Make sure the resistor’s leads are formed so they don’t touch anything but the two pins, and make sure you don’t create any solder bridges.
Again, this is a pulldown resistor that will keep that pin from floating up from ground potential when it first comes up in its reset state.
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#1 by Patricia Turpin - AB4CT at August 12th, 2012
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I went to the Control Panel and removed Lazy Dog Engineering, then HDSDR – did not remove the USB driver. I installed HDSDR first then
opened the LD-1B and removed the transmitter board.
Went to the Lazy Dog director and ran LD1Conrol … went to file then Update firmware.
ran USBBootloader & the LD-1TR hex file. All goes well then RESET.
Installed HDSDR 2,15 … and reassembled the TXmit board. Still haven’t pushed it back into the case!
Ran HDSDR & the LD1Control pops up with an error message “Unable to load ExtIO_Si570.dll” I click OK and the LD1control start up displays — click OK (everything looks good with new options).
BUT… if I go to HDSDR Options [F7], and select SDR TXsupport, I get this error…
Actual ExtIO DLL Does not support TX!
Because of this, I can not select any transmit Input or Output Soundcard connections.
I can use the LD1Control TX button and the red light comes on. I am not using the accessory plug ( I have the parts but not built it yet)
I have done this multiple times.
I know I’m probably not holding my tongue in the right place.
Anything obvious??
Patricia AB4CT
Montgomery, AL