Bendix King KMD150
 

So fitted new Saft battery, refitted unit, battery fail now gone.
Unit started up ok but thought it was off the coast of Africa.
OK i thought it will sort itself out.
So next day goes back to default 1/Oct/1998 position Goodwood.
Trying to set date and time, won't save nor position to speed things up.
Run for 15 minutes, not picking up any satellites.
STATE:No STATUS is the message gps page.

One would have thought battery holds the time/date/int. posn data.
Anyone any ideas, what's missing?

I did the same to a Skymap 3C a few weeks ago - IIRC they are the same internals…
Old generation GPS receiver needs a very good view of the sky, and a long time to find the first satellite, i think it took about an hour, once it found the first the others came along fast.
We are spoiled by the new generation with super fast acquisition times !

Has this anything to do with a change in satellite time code? My Garmin Etrex needed an update from Garmin a few years ago. (Still not done as it needed an XP computer. It works for nav but not astro data)

Well removed the battery and the unit works normally, but for not remembering time/date or user preferences.
Have ordered another battery.
Tried to be clever and fitted a battery holder rather than the tagged battery, with non tagged AA type battery.
Now ordered a tagged, axial battery.
Will try that, if not, will just leave out for good.

Well, bought another battery, Saft 3.6v axial tagged, soldered in, all working normally now and remembering presets and date/time setting.
Bit of a mystery why it didn't work first time around.