QO-100 / 2.8KHz SSB-transmission bandwidth

[HB9GIH]

How to establish fixed user defined persistent split between 2 VFO's or elsewise?

How to increase the SSB-transmission bandwidth?

If someone got a clue, I am very happy to know. Maybe I just overlooked issues easy to find, then my unnecessary post I please to excuse.

[5B4AIY]

Hi,

To answer your second question first, Page-2 of the User Configuration setup has facilities to allow you to adjust the narrow and wide RX bandwidths, and also the TX bandwidth. See page 17 of the TRX-2 User manual.

As for a fixed split, at present the software does not have a feature for this, you have to set the split manually each time you use the SPLIT feature. There is no intrinsic reason why this could not be accommodated into the firmware, but since I do not use this feature myself, and no-one has ever requested it, I have not incorporated it.

As it would require an additional word of EEPROM memory to remember both the direction and magnitude of the fixed split and whether to enable or disable it, then any such modification would cause a CHECKSUM ERROR on startup as the EEPROM memory map would have changed, and the defaults would be loaded, so you would need to save your existing calibration and configuration values prior to loading this new version.

Regards,
Adrian Ryan, 5B4AIY

[HB9GIH]

Re: QO-100 / 2.8KHz SSB-transmission bandwidth

Postby hhmze » 07 Jun 2024 12:24
Good afternoon Adrian

Well? It makes sense, that a fixed split configuration in the JUMA firmware is embedded.

The use case of/for the Juma TRX2A is for the satellite Es’hail 2 (QO-100). In order, what kind of uplink/downlink configuration you choose, an fixed offset makes a lot of sense.

73 HH HB9GIH

[HB9GIH]

Hi to the community.

I actually feel embarrassed to ask most probably a stupid question

"To answer your second question first, Page-2 of the User Configuration setup has facilities to allow you to adjust the narrow and wide RX bandwidths, and also the TX bandwidth. See page 17 of the TRX-2 User manual."

Sorrowly I didn't find it. Maybe I got an out-dated user-manual. Please does somebody point me exactly where to look at and interlink me maybe also to the right document and repeat the version of firmware it concerns.

73 HH HB9GIH

[5B4AIY]

Attached to this post is the latest version of the User Manual, for firmware version 7. On page 17 in the User Configuration section you will find the RX and TX B/W adjustment feature.

As for the fixed split, I can see that for satellite communications this could be useful, but this is so specialised I doubt that there would be many applications for it. It would take quite a bit of modification to the existing firmware to incorporate such a feature, and sadly we have already run out of knobs and buttons even with second functions, and I am really unwilling to consider adding tertiary functions to the buttons and knobs, so I have to say that with this last version of the firmware we have really reached the end of the road for this lovely little gem. Sorry, but I don't think I can usefully add any more functions/features to it. Even adding the last feature, TX Delay, to allow it to be used with a SPE linear amplifier was only just feasible, and even then I have to say that because of the hardware limitations, DATA mode operation with a linear would really require the use of an external sequencer to be 'bullet proof'.

Nevertheless, I am perfectly willing to continue to provide hardware and firmware support for the foreseeable future for this little rig provided that it is within the hardware/software/memory limitations.

73, Adrian, 5B4AIY