[time-nuts] HP 5061B
EWKehren at aol.com
EWKehren at aol.com
Sat Sep 3 14:46:53 UTC 2011
Jeff from your description it is not clear wether the noise is due to the
UPS or 5061B. The 5061 transformer most likely will complain with a crappy
signal input.I do not trust the output from UPS since many have a crappy
output which is ok if your PC does not have PFC on the input.
I have in the past always used and recommended to run the units from 28
Volt direct, not even using the AC input. Batteries do not have to be deep
cycle since power failures are not that prevalent and batteries will die from
chemical deterioration rather than cycle use. Low voltage cut out is
mandetory since car batteries will fail after a few full discharges.For instance
Costco car batteries have long warranties and combined with a Guest dual 12
V 5/5 charger makes a perfect set up for less than $230 and run time will
be about 24 hours. If you do not mind making small changes to the A2
charger board you can get the same result for half the price supplying power from
the 5061B. I prefer the Guest approach and I have noticed a price
escalation on Guest chargers but you can still get one for $110 shipping included.
In a message dated 9/3/2011 6:32:19 A.M. Eastern Daylight Time,
w3kl at w3kl.com writes:
We lost power for several days after the hurricane last weekend. As a
precaution I pulled the AC plug for my 5061B from the UPS it's attached to
since I was pretty sure that we would be without power for a while and didn't
want to have the unit plugged in when the power came back in case there was
Power was restored on Tuesday but I only got around to powering up the
system this morning.
When I plugged it in, it immediately started making a buzzing sound -
alomost like an alarm. The system appears to be working normally otherwise -
alarm LED on, clock advancing, etc.
I've never heard this buzzing before during power up.
Not knowing what the issue was, I powered the system down.
Anyone have any clue before I start tearing it down?
BTW - I don't see any mention of this in the manual.
Thanks in advance.
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