Hi I would bet the power supply is some sort of “brick”. That could make it a bit tough to replace.
Bob > On Dec 11, 2014, at 4:46 PM, Dr. David Kirkby (Kirkby Microwave Ltd) > <[email protected]> wrote: > > On 11 December 2014 at 01:10, Bob Camp <[email protected]> wrote: >> Hi >> >> I suspect that if you look closely at the board in the unit, it’s got water >> stains on it …. >> >> Bob > > I suspect you might be right Bob, but I am not going to break the seal > to open it up to find out. I will be contacting the seller, to see > what they offer. > > Does anyone have any experience with these having the voltages going > unstable? These two log entries show the 15 V is going both too high > and too low. > > Log 004:20141017.00:00:11: 15V is out of tolerance, value: 16.62 > Log 007:20141017.00:00:11: 15V is out of tolerance, value: 13.78 > > This shows the 5V rail has gone too high > > Log 078:20141210.00:00:11: 5V is out of tolerance, value: 5.54 > > This shows the oven current is out of spec - whether it is too high or > too low is anyones guess > > Log 022:20141205.04:42:26: Primary oven current is out of tolerance, > value: 115.81 > > I'm guessing the 115.81 is mA, but I don't know. If it is mA, 116 mA > doesn't seem an unreasonable number. I assume this will have an > oscillator "similar" to a 10811A - lets not worry about the exact > type. According to the data sheet for the 10811A, the oven resistance > has a minimum of 42 Ohms. Supply voltage is 20-30 V. So a quick > calculation shows the turn-on current could be as high as 30/42 = 714 > mA, so 116 mA doesn't sound unreasonable. The 10811A data sheet says > the power consumption is typically 2 W steady state at 20 V. So that's > a current of 0.1 A @ 20 V, so once again, 116 mA seems quite normal > for a steady state value, and a bit low for heating up. > > I've not opened a case on eBay yet. I will do at some point, but would > like to know the likely fault on this. The fact it does actually work, > probably indicates there's nothing too serious wrong with it. I > suspect a cap(s) is failing, which is quite common with age, and > fairly easy to fix. > > Having looked carefully, there are a few tell-tale signs this case is > actually not an original HP one, but I am not overly bothered by that. > It looks good, and if the unit worked, I would be happy. > > It is rather annoying that people leave this seller positive feedback, > or no feedback if they get their complaints resolved. I've had a few > people email me about this seller, but they all seem keen not to say > anything on a list, and looking at the feedback of the seller, it is > still 100% positive. There is definitely something fishy about this > seller, but the 100% positive feedback does not reflect that. > > I also wonder why they cleared the log, as the first log entry shows > Log 001:20141017.00:00:00: Log cleared > > I wonder if they had problems that they thought they had solved? > > Dave > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
