OpenGD77 Instructions by Ian Spencer DJ0HF v5.1A      7.6.2021
Voice and Beep function in the GD77
Turn the GD77 on.
If you have uploaded the voice prompts then they will automatically be enabled in level 1 in the official version and level 3 in Joe’s version and so you only need to change the menu item if you want to use a different level. The first level that is the default Level 1, voices all the menus but only the channel and talk group etc. when you hit the black SK1 button ( button just below the PTT). The second level is like the first but if you are voicing a talk group and change something else while it is speaking it will automatically begin voicing the new information, this is called follow on and the third level voices everything all the time without you hitting the SK1 button. Level 2 works slightly differently in Joe’s version. 
If you want to change the voice prompt level then you do this by pressing the green menu/ok button (top left on the keypad)  followed by the up arrow key 4 times
and then the green menu/ok button again
followed by hitting the up arrow key once
followed by hitting the right or left arrow key to change to the level you want to use and then just to confirm your selection press the green menu/ok button one last time. You can of course change your selection later if you want to at any time. In the following description I will be using Voice Prompts Level 1 (the Default)
Using the Voice Prompts
When you turn on the radio you should be in your Home Zone as you only created one zone in the code-plug, so you don’t have to worry about selecting a zone.
Whenever you change the channel using the up arrow (top row middle button) or down arrow (second row middle button) on the keypad you can voice the channel name by hitting SK1 on the side of the radio (black button directly below the PTT). If you are not changing the channel but just want to know what channel the radio is on then just hit SK1 again. If it tells you the talk group because that was the last thing you changed then just hit up arrow (up 1 channel) followed by down arrow (down 1 channel) to put you back on the original channel and hit SK1.
As you will have guessed from the last paragraph a similar system is used for Talk-groups. If you hit right arrow (second row right hand button) you will go up one entry in the talk-group list and if you hit the left arrow (second row left hand button) you will go down 1 entry in the talk-group list. Hitting SK1 will announce the talk-group.
Pressing the green menu button (top left button the keypad) will announce menu and whichever menu you are currently on. Hit the up arrow button or down arrow button on the keypad and each new menu item will be announced each time you hit the up or down  arrow button. To hear items in this menu hit the Green OK/Menu button again and you are taken to the second level and can use the up and down arrow buttons to go through the items and the left and right arrow keys to change them or if they are numeric values use the keypad, in any case use the Green OK/Menu button to confirm the selection or the Red Cancel button to exit without saving. 
The GD77 has two modes of operation, channel mode and VFO mode. Normally you are in channel mode  but if you want to switch to VFO mode then press the red cancel button (top right on the keypad) and if you press SK1 in VFO mode it will announce the receive and transmit frequencies stored in VFO A.  If they are the same then just the frequency will be announced and just once if they are different (repeater) then both will be announced with the words receive and transmit in front of them. To change the receive frequency just type a new frequency on the keypad after you enter the last digit the frequency will  be read back to you. So if you want to enter 434.1 then enter 434 then the GD77 will say point and then continue the frequency entry with 10000. If the original receive and transmit frequencies were different then OpenGD77 will assume you are using a repeater and will also alter the transmit frequency with the same frequency split. If you want to alter just the transmit frequency then while in VFO mode just hold the blue SK2 (Bottom button on the left side of the radio) and press down arrow. Now you can enter a frequency just as for receive and you have changed the transmit frequency. 
Using the Beep function
Pressing the up arrow key will take you up through the channels you configured for this zone and pressing the down arrow key will take you down through the list of channels. Each time you press a key it will beep and when you reach the first channel in the list it will beep with a higher tone to tell you that you are on the first channel. You can then press the up arrow key a number of times to reach the channel  (repeater or hot-spot) that you want to use.
Selecting a talk-group works in the same way using the left and right arrow keys allowing you to find the first talk-group and then click the right arrow key until you reach the talk-group you want to use. Pressing the PTT for half a second or so will now select that talk-group in your hot-spot or on the repeater and you can begin using it but be careful that someone is not already on using the repeater. Remember a repeater will automatically deselect the talk-group if you don’t use it for 10 to 15 minutes or so, a hot-spot will stay connected to that group until you select another as it’s your own personal repeater.
If you hit the star/asterisk key it will toggle between Time Slot 1 and Time Slot 2 with a high beep for TS1 and a low beep for TS2. If you are in Voice Level 3 then the time slot will be voiced or if you are in voice Level 1 then you can voice it by hitting SK1.
If you hold the blue SK2 button (lowest button on the left hand side of the radio) and hit star/asterisk then the GD77 will toggle between DMR and Narrow band FM. With a high tone for DMR and a low tone for NBFM.  Again if you are in Voice Level 3 then NBFM will be announced. DMR is not announced as the Talk group is announced and so you know you are in DMR mode and if you are in voice level 1 then you can hit the SK1 button to announce NBFM or the DMR Talk Group.
And now some other functions available on the GD77
If you hold the SK2 button (Bottom button left hand side) and hit the left arrow key then you can reduce the power from maximum to a minimum of 50 milliwatts in a number of steps each change will produce a low beep and when you reach the lowest power setting there is a high beep. 50 milliwatts the lowest setting is ideal for use with a hot-spot. Holding SK2 and hitting the right arrow  key increases the power in steps from  50mW, to 250mW, 500mW, 1 Watt, 2 Watts, 3 Watts, 4 Watts and the highest power 5 Watts.
Although not essential you might want to reduce the display brightness to 10% to extend the battery life. Hit the green menu button (top left button on the keypad) then hit the up arrow key 5 times to take you to the display settings. Hit the Green menu button again and you are on display brightness which is probably set to 100%, hit the left arrow key  9 times to set the brightness to 10%.  Hit the Green menu button again to confirm and you are done.
OpenGD77 has many more functions, too many to cover here but here are a few :-
Unless you set up filters your GD77 is always listening in Promiscuous mode that means if you are listening to a repeater you will hear everything that repeater is transmitting whatever talk-group it is on. This means for example if you have your GD77 on TG91 and the repeater is working at the moment on TG2350 then you will hear anyone on the repeater but if you transmit you will transmit on TG91 and they won’t hear you and you will switch the repeater to TG91. So if you hear someone and want to work them, if you hit the Blue SK2 button (bottom button left hand side) while someone is talking it will put your GD77 on their talk group and then when you transmit they will hear you. If you are using a hot-spot normally it will only be monitoring one talk group, though it is possible to configure a hot spot to monitor more than one. If you change the talk group on your GD77 remember to transmit for around half a second to your hot spot to move it to the same talk group.
If you want to use a talk group which is not in your code plug then you just need to hit the hash button, enter the talk group number on the keypad and then hit the green menu/ok button and your GD77 is on that talk group.
If you want to go to a reflector rather than a talk group which you may want to do if you use the DMR+ or Phoenix networks then you enter it the same way as for a talk group but enter a number between 4000 and 5000.
If you want to make a private call then press the hash key twice and enter the dmr id of the person you want to speak too and then press the green ok button. Now you can talk to that person if they are on the network. To return to normal talk group mode just press the right or left arrow key to select a talk group.
 If you would like to loan your GD77 to a friend. If you type hash 3 times (bottom right on the keypad)  and then hold the sk1 key (just below the ptt) and hit the hash key again you get the dmr id on the screen and can enter a new dmr id from the keypad. If you confirm with the green ok/menu button (top left on the keypad) then it will only remain in operation until you power off the radio and then it will revert back to the original DMR id. If you want to store the new id permanently then confirm by holding the Blue SK2 button (Bottom button on the left hand side) and press the green ok/menu button.