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HP9114A Replacement Battery Box HP88014B
04-29-2021, 11:10 AM (This post was last modified: 04-29-2021 12:25 PM by pamphonica.)
Post: #17
RE: HP9114A Replacement Battery Box HP88014B
(04-28-2021 08:54 PM)Dave Frederickson Wrote:  I'm having more concerns with this design. It seems that the DC adapter for the Battery Box can only be used to charge the battery as the adapter current necessary to power the 9114 would be too high to connect to the battery. A charging circuit would be needed.
So, either the battery can be charged with a charger like this one,, or the battery can power the 9114, but not both.


All points noted. This exactly why putting ideas up on this forum is so valuable!
1. I'll do a version of the front panel with a single 2.1x5.5 socket instead of 4mm sockets. The 4mm sockets were convenient as I never put a high-current source on devices like this. I envisaged an external psu giving say 100mA (limited) trickle charging current which would still be fine as the battery would supply the bulk of the current when the disk drive was operating. For initial charging I used the incredibly useful RipMax Pro-Peak Prodigy II all-in-one charger. £60 new but only £15 secondhand on Ebay.
2. I could stick a small 100mA current limiter inside the pack and that would allow any external source to be used.

Any other comments gladly accepted. I've passed a copy of the OpenSCAD source to Craig Bladow and am happy to pass it on to anyone else who fancies modifying this design.


Jeremy. HP restorer/collector/user. HP85/86/87 and HP41/71/75. HPIB and HP-IL testgear and peripherals.
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RE: HP9114A Replacement Battery Box HP88014B - pamphonica - 04-29-2021 11:10 AM

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