Thanks to a fellow member, I very recently sourced a replacement power supply for my wayward 540c and even more wayward re-celled 540c battery, of which I posted here long ago.
I can now report several things of interest.
First, using this new PS, the re-celled battery charges and all is well.
Second, using the variety of utilities available for the 540c, I have managed to revive the original battery that came to me with the machine, and was astonished to get a 70 minute (!) charge out of it on the first cycle after perhaps 7-10 years of neglect. Try that with a Lithium Ion cell. Total running time is now reported as up to 3.5 hours with both batteries, but this remains to be confirmed.
Third, and most interesting, the power plug on the new-to-me PS is missing the little black 4-hole plastic centre, which for some reason broke away in days of yore. This piece of plastic in the centre of the plug is meant to guide the relevant bits of metal to their appointed goal when you plug the thing in: male on the machine, female on the PS connector. All that is left on the latter are the THREE small female receptacles. The fourth of the holes in the plug is evidently a dummy.
I found with my original PS that it would very occasionally charge the battery and run the machine, which leads me to wonder whether the trouble with the original might be that little black plastic 4-holed centre preventing a good connection being made. The trouble is not, as might be thought, the usual solder on the power connector at the logic board, as I have had the logic board out and have done a close inspection — it is sound.
I am inclined to sand this offending piece of plastic down on the original PS so as to allow for a better mating of the connections, i.e., to allow the male connectors to go further into the black plastic thing which contains the female connectors. However, before I try this small piece of surgery, have any others experienced similar flakiness in relation to the power connector on a 540c?
I can now report several things of interest.
First, using this new PS, the re-celled battery charges and all is well.
Second, using the variety of utilities available for the 540c, I have managed to revive the original battery that came to me with the machine, and was astonished to get a 70 minute (!) charge out of it on the first cycle after perhaps 7-10 years of neglect. Try that with a Lithium Ion cell. Total running time is now reported as up to 3.5 hours with both batteries, but this remains to be confirmed.
Third, and most interesting, the power plug on the new-to-me PS is missing the little black 4-hole plastic centre, which for some reason broke away in days of yore. This piece of plastic in the centre of the plug is meant to guide the relevant bits of metal to their appointed goal when you plug the thing in: male on the machine, female on the PS connector. All that is left on the latter are the THREE small female receptacles. The fourth of the holes in the plug is evidently a dummy.
I found with my original PS that it would very occasionally charge the battery and run the machine, which leads me to wonder whether the trouble with the original might be that little black plastic 4-holed centre preventing a good connection being made. The trouble is not, as might be thought, the usual solder on the power connector at the logic board, as I have had the logic board out and have done a close inspection — it is sound.
I am inclined to sand this offending piece of plastic down on the original PS so as to allow for a better mating of the connections, i.e., to allow the male connectors to go further into the black plastic thing which contains the female connectors. However, before I try this small piece of surgery, have any others experienced similar flakiness in relation to the power connector on a 540c?