Start with this, see if it helps.
http://www.k4usd.org/CS700_K4USD.rdt
If you can't program that directly, I think you can use this to change the file to put into that radio
http://n0gsg.com/contact-manager/
30 seconds of Google produced this info.
It seems that the contact manager will allow you to take most any input type codeplug and out put it into what you want tytera and connect systems and retevis and somebody else wise.
Just remember just asking for a code plug for one of these radios for regional system means that somebody or a group put massive hours of work into typing it up so you can have it. They do not magically appear by themselves. So if you do happen to use a codeplug somebody has posted on a website and they have a donate button, consider doing that as they put their time into doing that personally just so everybody has a resource to go to.
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