Family Hoof
Well-known member
Greetings all! I have been visiting this forum and the older ones periodically for quite some time, absorbing all of the knowlege I can. Now I finally have a question that I couldn't find the answer for and so I make my first post.
I've recently decided to do some DIY 1272s so I'm building the BA283AV cards from scratch and have been slowly assembling my parts order lists. So far so good except for some confusion with the capacitors.
I'm using a scan of the original schematic dated May 15, 1971 and am trying to stay as close to this original as possible. I assume that all of the polarized capacitors are electrolytics, namely aluminum, and have been able to find all but one. The 400uF / 4V (C17) does not seem to exist and neither does 390uF @ 4V or anything similar. I thought of using a 1000uF and 680uF in series but cannot find both of these with a 4V rating either. Even outside of electrolytics I can't find anything which isn't SMD with this spec. What do I do?
Also, as for the rest of the caps (non-polarized) in the schematic, I know some are supposed to be tantalum and others polystyrene (or not? correct me please), but how do I know which are which? I'm trying to answer this question myself based on the SCA and JLM versions but any help would be appreciated.
THANKS!,
Jens J.
I've recently decided to do some DIY 1272s so I'm building the BA283AV cards from scratch and have been slowly assembling my parts order lists. So far so good except for some confusion with the capacitors.
I'm using a scan of the original schematic dated May 15, 1971 and am trying to stay as close to this original as possible. I assume that all of the polarized capacitors are electrolytics, namely aluminum, and have been able to find all but one. The 400uF / 4V (C17) does not seem to exist and neither does 390uF @ 4V or anything similar. I thought of using a 1000uF and 680uF in series but cannot find both of these with a 4V rating either. Even outside of electrolytics I can't find anything which isn't SMD with this spec. What do I do?
Also, as for the rest of the caps (non-polarized) in the schematic, I know some are supposed to be tantalum and others polystyrene (or not? correct me please), but how do I know which are which? I'm trying to answer this question myself based on the SCA and JLM versions but any help would be appreciated.
THANKS!,
Jens J.