[time-nuts] HP Z3801A Internal Power Supply issues

Bob Camp kb8tq at n1k.org
Sun Jan 31 11:42:19 EST 2016


Hi

I had one that took out the internal fuse once every 3 to 5 years. After 
replacing the fuse 3 times, the supply died. Go figure … only 15 years or use.

Bob
> On Jan 31, 2016, at 9:11 AM, paul swed <paulswedb at gmail.com> wrote:
> 
> As I mentioned in the another thread this week.
> You can indeed replace the failed voltage with just another inverter.
> Mine has run this way for 10 years. Mine was a 5 by the way. If it was one
> side of the +/-15 I would say you want to replace both.
> The entire switcher can be replaced with supplies that work off of 110 so
> you can get rid of the 48 volt supplies.
> Good luck
> Paul
> WB8TSL
> 
> On Sun, Jan 31, 2016 at 12:04 AM, Alex Pummer <alex at pcscons.com> wrote:
> 
>> power supply runs for a while, output current increases, but voltage stays
>> correct -> problem is in the load circuit, load circuit working for a while
>> load current increases, but it recovers after pause -> look for some
>> tantalum capacitor in the load circuit, they recover often  a few times
>> before they finally die,
>> KJ6UHN
>> Alex
>> 
>> On 1/30/2016 6:21 PM, Artek Manuals wrote:
>> 
>>> My Z3801A began to die over the last few days. It would work for an hour
>>> or two then produce a receiver error and communications problems. Turn it
>>> off, let it sit awhile, back on and it would start the survey and then
>>> begin to recover. Tonight it finally went dead with high current on the
>>> main input . The feed supply has a 2amp current limit so I have not blown
>>> the two 3amp fuses
>>> 
>>> I have a schematic of the supply reverse engineered by Stefan Hegnauere a
>>> few years ago (thank you very much) and a limited theory of operation
>>> description so I am not totally dead from a troubleshooting point of view
>>> although if one of the DC-DC converters is dead then I will likely have to
>>> scrap the supply
>>> 
>>> Questions
>>> 1) Any prior experience as where to look first I checked the
>>> electrolytics and at first glance they seem fine, no loss of magic smoke or
>>> any parts obviously hot or bulging. ESR 's look good on those
>>> 2) Will this supply function unloaded while I troubleshoot it on the
>>> bench out of the unit?
>>> 3) Anyone tried independent powering the Z3801? looks like two 5V
>>> supplies and +/- 15V..not hard to to do
>>> 4) Anyone with a good supply from a parts unit want to part with same?
>>> 
>>> Dave
>>> NR1DX
>>> ArtekManuals.com
>>> 
>>> 
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.



More information about the time-nuts mailing list