My sounder screen is glitching out. Is it possible to wire up another generic screen to show depths or must it be exactly the same one

It will depend what frequency you have. Most of the cheap shallow water sounders are 200hz but some are 160hz. If you have the right frequency it might be just a matter of converting plugs.

Thanks for the replies. The screen plays up. Displays unreadable numbers but eventually shows the depth. This started happening the night before I was to go up the narrows... I went around instead!

Fix it with a length of rope with a lead weight at one end and a few knots tied at even intervals along its length.

Work out how far to stand and away from the screen and hold onto a knot and start swinging the lead weight around your head, at the right time let go of the rope, smashing the screen to tiny pieces.
And it that fails. Drop the weight over board and count the knots until it stops

advantage of modern technology
is still readable use it. or dump it
upgrade to newer model

Steve, how about one of the cheapo fish finders, the ones that the transducer hangs of the transom. The transducer can be siliconed / epoxied in the bilge and they fire through all but steel, depending on how it's mounted it could be forward scan

Steve,
Without a pic of the screen when in the fault condition, it's not easy to diagnose the cause.
However, a very common cause of LCD display problems is the connector which attaches to the display and carries the signals to it.
The connector usually has worked loose, it's contacts need cleaning or there is insufficient tension of the contacts.
This problem can usually be rectified by a competent electronics technician.
regards,
Allan

On R the Navman screen died and l replaced it with an i40 screen. Both work at 200hz.
Hooker up all the wires and depth and water temperature worked fine with the original transducer, however, the water speed transducer despite the new impeller, never cooperated.
I had water temperature and depth which kept me happy.