I once read that Supercapacitors come up short in handling really short spikes, and that this is not due to physical inductance arising from the structure. Rather, the issue was of a subtle (to me) electrochemical nature.
Can anyone either confirm or refute this? Inquiring minds want to know. Dana On Fri, Oct 11, 2019 at 2:01 PM Bob kb8tq <kb...@n1k.org> wrote: > Hi > > Indeed, the unit seems to work fine without batteries. > > ------- > > If filtering and short duration spikes are the concern, one could > replace the batteries with super capacitors. One would *hope* they > are a bit less likely to create problems. …… > > ----- > > While it is a good idea to keep OCXO’s on power, a half hour or > couple hour outage is not that big a deal. They will settle back down > pretty fast after that sort of interruption. Unless the rest of the lab is > on backup power, there may not be a major need for the 105 to stay > up and running …. > > Bob > > > On Oct 11, 2019, at 11:59 AM, Jeremy Nichols <jn6...@gmail.com> wrote: > > > > The 105A was built without a battery. The 105B has a battery and charger. > > > > I have a 105B that had the failed battery removed before I bought it. It > > works fine. I have it on a UPS; it survived our just-finished NorCal > power > > shutdown just fine. > > > > Jeremy > > > > > > On Fri, Oct 11, 2019 at 7:01 AM Scott McGrath <scmcgr...@gmail.com> > wrote: > > > >> As one who owns a 105 i had the battery properly rebuilt and basically > >> have it on low rate charge and periodically discharge the battery > >> > >> When rebuilding a 105 battery it’s important to replicate its > >> characteristics > >> > >> Remember HP also intended I believe that the battery would also serve > as a > >> filter for the power supply. As I dont recall any version of the 105 > >> without a battery. > >> > >> > >> > >> On Oct 10, 2019, at 4:50 PM, Taka Kamiya via time-nuts < > >> time-nuts@lists.febo.com> wrote: > >> > >> The fact that 25V supply is dropping to 23.4V shows it is drawing far > more > >> current than it is rated. I am assuming this is a regulated power > supply. > >> Does the power brick actually shuts down at 500mA or does it let the the > >> voltage drop and try to supply what it can? Maybe one or more Nicad > has an > >> internal short? That will cause and over-voltage situation per battery > and > >> thus over-current. I've recently seen a brick power supply go into > >> oscillation and produce 3x rated voltage when too much current was > drawn. > >> (and blew the circuit) > >> > >> Also, different batteries has different charging rates. As far as 105B > >> document goes, it says 24V 0.5Amp supply but that is for default > >> configuration. Designed charge rate is 390mA (page 3-4) and is current > >> controlled by A5Q3. > >> > >> I would actually measure how much current is drawn there. Since the > fuse > >> is already blown, just put an am-meter across the fuse and see.... > >> > >> --------------------------------------- > >> (Mr.) Taka Kamiya > >> KB4EMF / ex JF2DKG > >> > >> > >> On Thursday, October 10, 2019, 4:00:41 PM EDT, Roy Thistle < > >> roy.this...@mail.utoronto.ca> wrote: > >> > >> Hi All: > >> A 105B (quartz oscillator) is blowing the 1A fuse, after it is on about > 1 > >> hour. > >> The fuse appears to have just melted (not a black mark as the result of > a > >> flash, in the case of a high current short.)… just looks like the fuse > wire > >> (inside the glass capsule) melted into some little blobs, for about 1/4 > >> the fuse length, near the middle. It wasn't a fast-blo or slow-blo > fuse... > >> just the normal kind. > >> I think the unit is drawing just a little too much current, as the > result > >> of the batteries needing charging (I had the fast charge option on when > the > >> fuse blew.) And so, the fuse heated up, and finally melted. Not sure why > >> the batteries were not charging normally... but 20.1 volts is what I > >> measured across the pack, initially, and 23.4 V after about 45 min of > >> charging. > >> I am charging the batters, from a power cube, at 510 ma, and dropping > >> (cube gives 25V, 500mA max)… the batteries are 20 C size NiCads, wired > in > >> series... that of course is a retrofit. > >> I don't want to put another fuse in, and blow that too, without some > >> reasonable explanation of why the first one failed! > >> Please, any comments, or hints/suggestions... much appreciated. > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > >> > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > >> > > -- > > Jeremy Nichols > > Sent from my iPad 6. > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.