That may be a very useful hint, John! Simple to check and repair.
I'll check the PSU and its startup behavior, although it seems that the problem with Ethernet connectivity is caused by the NVRAM battery failing, resulting in intermittent running of the clock and loss of the MAC (hardware) address. I found a complete description of my problem, complete with cause and all symptoms, on EEVBlog.
Raymond
toggle quoted message
Show quoted text
On 20-sep.-20 20:55, John Gord via groups.io wrote:
Raymond,
I have seen several TDS30XXB scopes with flaky power supplies. The problem is in the optoisolator used for feedback, which looses gain with age and demands too much current from the TL431 reference, causing the supply to sag and the reference to overheat (and sometimes die).
Check to see if the power supplies are behaving during startup. I am not sure, but you might be able to monitor the supply adequately via the +15V output jack on the back.
--John Gord
On Sat, Sep 19, 2020 at 03:30 PM, Raymond Domp Frank wrote:
I recently acquired a TDS 3014B 'scope.
It looks fine and operates as it should, except for its LAN interface.
In the beginning (first half day since I got the 'scope), it could sometimes
be configured and would be OK for a while, then stop after a few minutes.
Now, after a few days, the LAN interface does not work at all and even hangs
up (blocks) the 'scope when I select the DHCP button in the LAN setup menu:
Immediately after I press the DHCP enabling button, the usual popup telling me
it'll try and acquire an IP address appears. After that, everything stays
frozen and no buttons or knobs respond. The only way to get out of that
situation is power cycling, however after that, the scope shows its normal
background, graticule, numbers etc. but no traces appear and it does not
respond to operating keys or knobs.
The only remedy seems to be power cycling while doing a Reset by keeping the
"B Trig" button depressed during power up.
This to me looks like a hardware/firmware failure. I haven't found a way to
completely disable/enable the LAN interface, thereby possibly resetting the
thing.
I'd very much appreciate any remedies, ideas or info.
Raymond
Raymond Domp Frank