With rigs like the ICOM 756 Pro 2 there is an additional command you can invoke to turn on "digital" mode with either USB-D or LSB-D.
Similar with at least some Kenwood rigs, even old ones such as the TS-440SAT, you can ground a specific pin in the 13 pin DIN circuit and that mutes the mike. I made a breakout box many years ago with 3 coax cable runs from the 13 PIN plug to RCA phono jacks. I realize that I can change the pin outs for the ICOM 7000 type rigs that require a different set of pins from the Kenwood but I cnan still use the same BOB. With the most basic interfacing, you can run from an interface, such as the SCI-6 kit from Unified Microsystems with three RCA phono cables, one for audio in, one for audio out, and PTT but you need to make up a different set of cables to fit different rigs, depending on what connectors they use. You must not allow the mike to be operating when doing digital modes in RTTY/data portions of the bands since it would not be legal operation if background audio was also being sent on the frequency. Only the tones from the RTTY/Data mode should be allowed to be transmitted. The exception can be on VHF frequencies that allow such use. Then you could even use "acoustic coupling" which is a very simple way to "interface" a rig to a computer without an interface. 73, Rick, KV9U Tooner wrote: > One of the things I enjoy about moving my SignaLink to the 735 is not > needing to switch out the interface and mic connectors. Now it seems > I might still have to exercise the same effort, disconnecting the mic > when using digital modes. > > Why is it a problem that the front-panel mic and the ACC1 jack is live > when transmitting? > > Frank, k2ncc > >
