Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

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ve7mdt
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Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by ve7mdt » Fri Dec 17, 2021 1:34 pm

I am not that familiar with the Hotspot mode operation of this firmware. My friend is going to give me his GD-77 that has a non-working LCD (not physically broken / cracked), and I am thinking of re-purposing it as a Hotspot unit. I wonder if not having a working screen would hinder any operational functions as a Hotspot? I understand that the GD-77S that doesn't have a screen can be used like that, but I just want to be sure. There might be a way of fixing the screen, but it isn't very obvious what's wrong at this stage (my friend is quite technical also but he hadn't had any luck.)

Another question: I only have RPi 2, and not anything faster / newer. Would it be sufficient to run the Hotspot software? (I can use other computers in the interim if it doesn't.)
73,
David
VE7ET / VE7MDT
DMR radios: D878UV, D578UV-III (not arrived yet), XPR 5550, XPR 4550, XPR 7550, SL 7550, VXD-7200, CS-800D, RD-5R, GD-77, RT3s, MD-340 (not arrived yet)
DMR repeater: XPR 8400 UHF

VK3KYY
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by VK3KYY » Fri Dec 17, 2021 8:49 pm

The LCD chip is Write Only, so the firmware does not know whether the LCD is even connected.

So... The radio will work even without a screen

However on first book the radio displays the Settings Update message, and you have to press the green button

Also by default hotspot support it not enabled and normally you need to enable it in the Options

However if you have another GD77 just set all the Options you want in that radio, then backuo the settings, and then restore the settings to the new radio


Re:RPI2

I tried PiStar on a RPi2 last year, and from what I recall it ran really slow to the point being usable.

You could try it but you may have problems using such an old RPi

LY1RF
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by LY1RF » Sun Dec 19, 2021 10:15 pm

Pi2 is more than enought for pistar .

ve7mdt
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by ve7mdt » Mon Dec 20, 2021 1:58 pm

VK3KYY wrote:
Fri Dec 17, 2021 8:49 pm
The LCD chip is Write Only, so the firmware does not know whether the LCD is even connected.

So... The radio will work even without a screen

However on first book the radio displays the Settings Update message, and you have to press the green button

Also by default hotspot support it not enabled and normally you need to enable it in the Options

However if you have another GD77 just set all the Options you want in that radio, then backuo the settings, and then restore the settings to the new radio


Re:RPI2

I tried PiStar on a RPi2 last year, and from what I recall it ran really slow to the point being usable.

You could try it but you may have problems using such an old RPi
Thanks, Roger. That's excellent.

I have my own good GD-77 so I can use it as a setting config and then reload it on the dead screen one. I just picked it up and it has a white screen but nothing shown on it. Rather sad.

I'll try using an x86 computer for the time being (may be an Atom netbook) until I pick up an RPi3 sometime.

I will still look at if I could fix the LCD problem, but if my friend can't, I am not holding out much hope. But I will read up on the GD-77 tips website just to see if others have this problem too.
73,
David
VE7ET / VE7MDT
DMR radios: D878UV, D578UV-III (not arrived yet), XPR 5550, XPR 4550, XPR 7550, SL 7550, VXD-7200, CS-800D, RD-5R, GD-77, RT3s, MD-340 (not arrived yet)
DMR repeater: XPR 8400 UHF

IW2FHM
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by IW2FHM » Mon Dec 20, 2021 2:36 pm

Hello, the failure of the disply, if it is all white, could be caused by the flat cable connecting the disply. In my two GD77s it was enough to reposition the cable in the two connectors.
Good luck, 73
IW2FHM Roberto

ve7mdt
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by ve7mdt » Mon Dec 20, 2021 2:55 pm

IW2FHM wrote:
Mon Dec 20, 2021 2:36 pm
Hello, the failure of the disply, if it is all white, could be caused by the flat cable connecting the disply. In my two GD77s it was enough to reposition the cable in the two connectors.
Good luck, 73
IW2FHM Roberto
Thanks.

When you say reposition do you mean moving it sideway a little? I am not sure how much clearance there is.

I did a reseating on both sides and it didn't work for me, more than once.
73,
David
VE7ET / VE7MDT
DMR radios: D878UV, D578UV-III (not arrived yet), XPR 5550, XPR 4550, XPR 7550, SL 7550, VXD-7200, CS-800D, RD-5R, GD-77, RT3s, MD-340 (not arrived yet)
DMR repeater: XPR 8400 UHF

IW2FHM
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by IW2FHM » Mon Dec 20, 2021 3:24 pm

I did it by disconnecting the cable completely, loosening the fasteners, and then repositioning it with precision.
Beware that the cable is very fragile, in one case I had to replace it.
73
Roberto

ve7mdt
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by ve7mdt » Mon Dec 20, 2021 5:33 pm

IW2FHM wrote:
Mon Dec 20, 2021 3:24 pm
I did it by disconnecting the cable completely, loosening the fasteners, and then repositioning it with precision.
Beware that the cable is very fragile, in one case I had to replace it.
73
Roberto
Thanks again.

I did that but that didn't help me.

I am familiar with these cables when trying to fix other devices and I agree with you that they are very fragile.

The display can display random dots (garbled totally) for a split second when turning on the radio, so I think between the LCD and the driver things are working. But there is something wrong with the LCD logic control, that it doesn't want to display anything or the right stuff. Thus, I doubt it is a cable or connection issue.

But thanks for your help!
73,
David
VE7ET / VE7MDT
DMR radios: D878UV, D578UV-III (not arrived yet), XPR 5550, XPR 4550, XPR 7550, SL 7550, VXD-7200, CS-800D, RD-5R, GD-77, RT3s, MD-340 (not arrived yet)
DMR repeater: XPR 8400 UHF

VK3KYY
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by VK3KYY » Mon Dec 20, 2021 7:42 pm

Sounds like a loose connection. You could try resoodering both ends of the ribbon cable

Also I heard of someone who bought a DM1801 LCD display and it fitted perfectly in their GD77

But its probably not cost effective to do this, as Radioddity have the GD77 in their Christmas sale, priced at less than $80 USA

ve7mdt
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Re: Can I use a GD-77 w/ non-working LCD as a Hotspot radio?

Post by ve7mdt » Wed Dec 22, 2021 5:36 pm

VK3KYY wrote:
Mon Dec 20, 2021 7:42 pm
Sounds like a loose connection. You could try resoodering both ends of the ribbon cable

Also I heard of someone who bought a DM1801 LCD display and it fitted perfectly in their GD77

But its probably not cost effective to do this, as Radioddity have the GD77 in their Christmas sale, priced at less than $80 USA
Talking about that, I didn't post to the General sub-group, as Radioddity is having a sale that has the GD-77 plus a speaker mic at $80 USD. The mic is probably so-so, but still worth about $10?, so that makes the radio at about $70. not too bad as price has gone up slowly in recent years on this model actually.

I think I will just use this unit as a Hotspot unit from now on. When the display shows the garbled random (like a snow/noise on an analog TV screen with no signal on!) briefly during power on, for around 0.2 sec, it was crisp and sharp and correct contrast. It means that the LCD was driven correctly to make such display, even for a split second. This is quite reproducible also.

If a spare cable can be ordered at a cheap price I might give that a try. But that's about as far as I would try to fix this prob.

(I am actually familiar with fixing the poor cable contact for the Motorola Jedi's LCD problem, and using the heat trick to get it back working again. This seems to be different than that, and that is a well known problem. I fixed quite a few Jedi series radios w/ this trick.)

I managed to get BlueDV on my Windows PC to get a good serial connection w/ the GD-77 running the latest public beta OpenGD77 FW. I haven't done any actual connections yet as Brandmeister isn't my goal here, and I didn't know BlueDV doesn't have the config open up for entry for our local Hotspot server connections. I will switch to MMDVM based s/w later on when I get an RPi or another PC to do it.

I also have confirmed that this GD-77 works well otherwise for TX and RX, the LCD is the sole problem right now.
73,
David
VE7ET / VE7MDT
DMR radios: D878UV, D578UV-III (not arrived yet), XPR 5550, XPR 4550, XPR 7550, SL 7550, VXD-7200, CS-800D, RD-5R, GD-77, RT3s, MD-340 (not arrived yet)
DMR repeater: XPR 8400 UHF

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