Originally posted by nevetslab
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Originally posted by nevetslab
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When I received my 7200A, literally *all* electrolytic capacitors in the PS turned out to be leaky.
I desoldered them, cleaned up the mess using some IPA and re-populated the board with the following replacements from RS Components:
3 pcs. 496-1814 (220uF, 450V)
6 pcs. 684-1775 (820uF, 50V) (only available high-performance replacement for 470uF, 40V with matching size)
2 pcs. 684-1740 (1000uF, 35V)
5 pcs. 653-9188 (100uF, 100V)
36pcs. 684-1725 (220uF, 35V) (only available high-performance replacement for 150uF, 35V with matching size)
Sometimes, one has to be careful when choosing replacement capacitors in a switch-mode power supply,
since the design could rely on certain parameters of the original caps which might change when choosing a replacement type too far off.
My 7200A runs beautifully with these replacement caps, so I think the choice was about right.
One more thing in the power supply is the green or black "Phoenix" brand connector.
It supplies the plug-ins with power (the thicker red/white and white/red cables). Apparently, it was underrated for the current drawn by the plug-ins,
and this lead to problems in some of the versions of the 7200A. The agreed solution to this (as advertised by LeCroy service personnel)
is to replace the connector and on the circuit board, connect the ground pins all together which seems to help distribute the current more evenly.
Should you need any EPROM dumps or programmed replacement parts, just let me know and I will send you backup images
of mine or burn them into new parts, which I could send to you via mail.
Originally posted by nevetslab
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The LeCroy service was so nice as to provide the source code for the PC software (ACQUIRE.EXE and SEQTRAN.EXE) which seems to be unobtainable nowadays.
I put these into my github repository along with an exemplatory python code to control the 7200A and fetch data from it: https://github.com/jonathanschilling/LeCroy7200A
Maybe this is of use for you too...?
This sounds like you are certainly well-enough equipped to get this system up and running completely.
All the best wishes from my side that you get this setup up and running smoothly :-)
I'll keep an eye then on the MEF's flea market for the 9100.
Originally posted by nevetslab
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In the end, the shipping expenses were as much as the device cost itself, but it certainly was worth it.
I searched the internet for the service manual of the 7200A, since I needed the power supply schematics to repair it beyond just replacing the capacitors.
As I did not find them anywhere, I asked the LeCroy service, who had some low-quality scans available which (for the moment) were enough to get the power supply up and running again.
However, you might probably understand that it is much more satisfactory to have a well-readable schematics at hand for the devices you use.
Not only can one learn from them (as e.g. from the old Tektronics oscilloscope manual as well), but I would like to e.g. build the external trigger board
which sadly was not included with by 7200A. So, if we could arrange in any way a shipping of the 7200A service manual, I would gladly pay any expenses.
Regarding the 7200A itself, I seem to understand that you would rather like to keep it for the moment? ;-)
Cheers,
Jonathan
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