Sound Card<–>Radio Audio Isolation
#2
(29-04-2018, 12:53 PM)VK2CSW Wrote: Would a pair of 1:1 transformers be enough?  Or would optocouplers be a better solution?

The 1:1 transformers like the 600:600 ohms versions available around the place  (Jaycar MA1512, though their MM5534 3K:3K is probably a better choice) are fine.   One for receive audio, one for send.
I have a homebrew interface that I am presently using for FT8 on HF and I have included potentiometers on the output sides (pot values not critical - 5K etc) so that I can set audio levels without resorting to changing any mixer settings in Windows.  They are connected through to the Accessories port on the radio and it gives constant level on receive and a level independent of the mic gain setting on transmit (Icom radio).

Optocouplers (ie LED diode + phototransistor device) are for DC-based signalling (on/off) and won't operate with direct audio.
Doug VK4ADC @ QG62LG51
http://www.vk4adc.com

This Forum is only going to be as interesting as the posts it contains. 
If you have a comment or question, post it as it may trigger or answer the query in someone else's mind.
Reply


Messages In This Thread
Sound Card<–>Radio Audio Isolation - by VK2CSW - 29-04-2018, 12:53 PM
RE: Sound Card<–>Radio Audio Isolation - by VK4ADC - 29-04-2018, 01:25 PM
RE: Sound Card<–>Radio Audio Isolation - by VK5ZD - 04-05-2018, 09:33 AM

Forum Jump: