We currently have 2 home made D-Star repeaters, GB7WB and GB3WE. GB7WB is our UHF digital only GMSK repeater on 439.4875MHz and GB3WE is our VHF dual mode FM/GMSK repeater on 145.6875MHz. GB7WB has been made from a pair of Philips PRM80’s and GB3WE is made from a Philips FX5000. Both repeaters, Nodes, DVRN or whatever you want to call them use some very simple logic and methods of detecting the presence of a valid signal before passing all of the data to the transmitter. We do not use any CODECs or decoding and although we plan to add the Satoshi boards soon, the repeaters are on the air in the most minimal form possible to enable us to evaluate them as well as to get on the air to use them and have fun. It is a nice and cheap way to get some good D-Star coverage and has been a great learning experience. This is just the very start of a much bigger exciting project.


As GB3WE is a dual mode 2m repeater it decides on initial access which mode you are operating in. It will stay in this mode until the repeater goes back to standby. If you access the repeater in analogue mode you will need to run CTCSS of 94.8Hz, 1750Hz tone burst is not used on WE. There are two pips which you need to allow between ‘overs’ or you will time-out.


At the end of use the repeater will send its call sign and go back to standby, where it may be re-accessed by either DV or FM. You cannot send a digital signal through the repeater while it is in FM mode, you need to wait for the repeater to close down and then re-access it with a DV signal. When you operate through the repeater in DV mode you will just get a 1 second hang time from the transmitter after you have released your PTT to indicate that you have accessed, so keep an eye on your S meter. 15 seconds after you have finished using the repeater in DV mode the repeater will send a CWID to indicate that the repeater has gone back to idle and is ready to be accessed by either digital or analogue users. Do not try to access the repeater using FM before it has sent its CWID as your audio will not be passed through the repeater.


Go to our photos page to have a look at our home brew GMSK D-Star repeaters. Also known as home made GMSK Nodes.