a 4N28 - 4N32 should work just fine.

John Wilson wrote on 3/20/2019 10:23:

Jay,

Thanks for the input and yes, I did do a search for an optocoupler, NPN but came back with a slew of options. Just didn't know if there were exacting standards on the specs but there again, if there were, they'd probably had put it out there.

I like your idea and that would definitely isolate it but I'm going to go with one of the 6 pin optocouplers. 

73

John 

On Wed, Mar 20, 2019, 12:36 Jay Henson <aj4ay@...> wrote:

John,

Do a google search for optical isolation circuits.  That will provide
you with a lot of info.

My homebrew digital interface uses a Radio Shack 276-142 infrared LED
and receiver.  The LED is on the computer side of the interface.  The
receiver is on the radio side.  Between the two devices is a piece of
shrink tubing, not shrunk.  The computer ground is completely isolated
from the radio ground.

Good luck & 73.

Jay
AJ4AY
Mobile, AL



On 3/20/2019 10:56 AM, John Wilson wrote:
> Looked at the link for the CW interface and am interested in the one
> with the optic coupler. Diws anyone have a part number for the coupler?
>
> 73
> John
>

--
Jeff K. Steinkamp (N7YG)
Tucson, AZ
Scud Missile Coordinates
N32.2319 W110.8477