Imagine that you would like a multi-repeater site, where you might have a UHF and a VHF repeater using the same logic or a mix of modes, where there was on one hand a VHF Analog Repeater and on the other a UHF Digital repeater.

Not that this has been achieved personally, but the opportunity is there.

So lets us suppose then we have VHF Rx1 and VHF Tx1, and UHF Rx2 UHF Tx2. I am not experienced enough in the Digital Modules that SVXLink offers to delve deeply here, but I shall concentrate only on the configuration within the svxlink.conf and its associated logic files.

In the svxlink.conf file the first few lines offer the opportunity to include the logics to be used. With two lots of transceivers there are two things to consider, not the least the inclusion of two sound cards and the added complication that provides.

So in /etc/svlink/svxlink.conf first paragraph we shall see

LOGICS=RepeaterLogic,NetLogic into which we need to add another instance of RepeaterLogicTwo in the line.

Necessarily this will require a copy section in the rest of the dialogue

[RepeaterLogicTwo] with all the profile relating to the different transceivers and sound parameters that will entail.

This is not all. This will also require an additional logic controller in the mix so that the configuration file will work correctly.

In the original build, those who have followed the very detailed instructions will remember, that the logic files are found at /usr/share/svxlink/events.d and are copied to a further ‘local’ directory created there, so that we protect the originals and svxlink works with the changes that we incorporate in the new folder.

[RepeaterLogic] works with RepeaterLogic.tcl in this location therefore it follows that we need an identical logic file for the [RepeaterLogicTwo]. This is very easy to do, by copying the original RepeaterLogic.tcl to RepeaterLogicTwo.tcl in the first instance, but we are require to edit this new file in nano (or vim) to change the name of the file in the first paragraph to reflect the new name. There is text in this paragraph to reinforce this requirement.

All that remains to be done is to ensure that the necessary GPIO ports controlling the additional transceivers are configured, and that the svxlink.conf file includes the changes of Rx1, Rx2, Tx1, Tx2, and the associated different sound devices are correctly edited.

This is no different to a repeater that has a duplex repeater with a simplex link, where both RepeaterLogic and SimplexLogic are coupled.

Needless to say, that unless we have a situation where we are likely to include so many devices it is certainly not plug’n play, and not for the faint of heart.

Whilst not yet operational F1ZNQ* a UHF repeater with a VHF link has been built by me and tested and found to comply with the requirements, and waiting for the opportunity to be installed when conditions permit.

*Three Motorola GM350 Transceivers, Raspberry Pi B+ and two USB Sound cards, and a Katherein Duplexer.

Idea stimulated by Tony Langdon VK3JED – I would have never considered it otherwise. Up for experimentation I think.

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