ThinkJet 2225B battery pack question

[hfischer]

Dave and Keith,

thank you for your answers - the photos and the link to the 2005 post by Etienne were extremely helpful!

Looking at all the photos, I came to the same conclusions as Keith: choke and 4.7 Ohms (the colour code yellow - violet - gold can be "guessed" on one of the photos).

I tried to roughly calculate the inductance of the chokes and arrive at something like 1 Microhenry. On Etienne's photos there are two chokes, the colour code of which might say 10 Microhenries. No idea how critical this may be, and whether the chokes are present to block spikes from the mains into the printer or whether they are meant to block spikes coming from the printer's internal voltage converter.

Anyway, I had just finished a tentative simple circuit diagram when your posts came up (see attachment). For Etienne's battery pack the chokes would be after the rectifier.

   

(hope this works - I can't see the attachment ...)

BTW: today I received a 2225C, cheap and intended for spare parts. The case is in a better shape than that of my 2225B, and this printer also works, at least the self test. And in a locker at my former workplace, a while ago I discovered a box full of inkjet paper which nobody wants :-)

Thanks for the links to ink cartridges and charger!

Stay healthy,

Helmut