IC-910H Main Band/Sub Band data sockets

[VK2DVZ]

Hi all,

Background to my question:

On 23cm I normally TX using a separate transmitter and RX via down converters from 23cm to 2m and from 2m to 28MHz, into a HF transceiver. There is a high power high isolation relay and preamplifier mounted on the feed horn of my 2.4m solid dish. Separated TX and RX feeders are in use. I also run a water cooled 2C39 PA in the shack. There is a sequencer managing all the relevant switching for TX-RX. Sounds complicated - probably is, but it works well.

HF rigs and transverters are also in use on the 2m and 70cm.

To use the WSJT digital modes I use my IC910, to take advantage of the available data sockets for easy interfacing to a computer. All straight forward for 2m and 70cm to just use the IC910 instead of my transverter systems as mentioned above.

On 23cm the fun starts. To be able to still use the existing PA, preamplifier, sequencer, etc with the separate TX-RX coax feeders with the IC910, I connect the TX side as usual to the 23cm N connector - all straight forward stuff. On the RX side of things I have to feed the received signal out of the 23cm to 2m Down Converter, and attach the coax to the 2m So239 connector - still all straight forward stuff.

Now, to ensure that the IC910 transmits on 23cm and receives on 2m only - NEVER THE OTHER WAY AROUND - I have to engage the SATELLITE command. This of course now makes the SUB-BAND the transmit band (so 23cm frequency is set here) and the MAIN-BAND becomes the receive band. I also have to ensure that the NORMAL - REVERSE satellite feature is set to normal, so that when the VFO knob is rotated, both the 23cm and the 2m frequencies track each other in the same direction.

Now this is where the real fun starts:

On an IC910, the received audio from the Data Sockets on the rear panel defaults to the MAIN BAND (normally the Uppermost, ie. the frequency displayed at the top of the display window). In Satellite mode the BOTTOM displayed frequency in the display window is now the TX frequency (in my case the 23cm TX frequency) and is recognized by the IC910 as the MAIN TX frequency, and the MAIN DATA Socket wants to receive audio from it. I want to be able to now listen to the original MAIN DATA SOCKET audio that is being receiving from the 144MHz down converter, but cannot because the IC910 sees the top displayed frequency it as the SUB BAND and audio out via this data socket is unavailable, even though this is the socket into which the computer interface is plugged into.

Now to my question - after such a lengthy build-up :

Is it safe to physically join the receive audio out pin of the MAIN BAND data socket with the receive out pin of the SUB BAND data socket?
I am proposing to achieve this by plugging in a second 6 pin mini DIN plug into the SUB BAND data socket and running a single shielded audio cable from pin 4 (data out) and ground, on each plug. An 1/8' audio plug/inline socket could be used for easy disconnect of the second DIN Plug when not needed.

As an aside, I have been able to achieve a 'temporary fix' by plugging into the IC910 mic socket and headphone jack, using a home brew multi-rig adapter leads that I have and manually setting the volume level for the WSJP programs on receive. Headphone audio out is only from the Top displayed frequency when in satellite mode, ie the 2m frequency audio that I want for the computer. With this arrangement I am unable to monitor the received signal audio through the rig speaker, as is normally available on the IC910 when using the regular Data Socket.

I am not expecting anyone to have experienced my problem, however I await comments/suggestions.

Regards,
Ross vk2dvz

[VK5ALX]

Hi Ross

I've been through all that. My fix is to take the signals from the ACC socket. It doesn't matter whether the radio is in normal or satellite mode, the audio always comes from the top (main) VFO

Cheers
Alex VK5ALX

[VK2DVZ]

Hi Alex,

....... My fix is to take the signals from the ACC socket. It doesn't matter whether the radio is in normal or satellite mode, the audio always comes from the top (main) VFO

Thanks for the advice.

Just wondering... is the ACC socket audio at fixed level, same as from DATA sockets and is speaker audio still available and adjustable?

Ross

[VK5ALX]

Audio is fixed level. Yes, speaker audio is still adjustable.
73 Alex

[VK2DVZ]

Thanks Alex for info, much appreciated.
73, Ross

[VK2DVZ]

Problem solved.
I made up a patch lead to marry onto my computer interface lead so that I have access the ACC Socket on the IC910, as suggested by Alex vk5alx. The required audio is now available.
Digital operations on 23cm using my PA / preamp combination should now be more easily achieved in my shack from now on.

Ross