Recapping a HIKI TR1667A Multimeter

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I got this older Hungarian made HIKI TR1667A desk multimeter I like to use on occasion. However I’m fairly suspicious of the capacitors inside, as I had another desk multimeter break due to a short circuiting electrolytic capacitor (I’ll make a repair post about that one some time). And the latter capacitors were still newer than the ones that are used in this thing, so I figured I’m going to replace them really quick to ensure that they don’t end up destroying ICs or the transformer.

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Resetting Password on a CISCO Catalyst 2900XL

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I needed to reset a password on an old CISCO Catalyst 2900XL, so here is the procedure as a reference: The following should work at least on all older CISCO Catalyst series switches, in my case this is a very old 2900XL. Hook up a serial terminal Hold the MODE button pressed until the switch is booted. Now something like this should come up: C2900XL Boot Loader (C2900-HBOOT-M) Version 12.0(5.2)XU, MAINTENANCE INTERIM SOFTWARE Compiled Mon 17-Jul-00 18:19 by ayounes starting.

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Quickie: New paint for a Karl Klein DNG 6-22,5

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I recently got this Karl Klein DNG 6-22,5 blower (22 m3/min) I want to use for dust extraction. Unfortunately the seller spray painted the whole thing with zinc spray w/o telling or asking me. This is what I got out of the box: It appears that they at least stripped off parts of the old paint (maybe even sand blasted it?) but like I don’t like this look. So I gave it a quick new paint job, first I removed some of the zinc spray where it was not sticking properly.

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Repairing a Siemens Schuckertwerke AC Motor

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Disassembly Te screws of the bearing covers were completely sheared off, probably from vibrational damage. New bearings Replaced the old bearings with new SKF 6200-2RSH ones. Odd screws The screws holding the bearing cover were of an odd dimension, either imperial or something like M3.5. I decided to rethread the inner plate to M4, so I can use standard screws. To do this I used a 3.5mm reamer to clean up the hole and re-threaded it to M4.

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Voltcraft Power Supply Maintenance

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I got a couple older power supplies from the Voltcraft brand, so I decided to clean them up a little bit: 12V 2A - Replacing Selenium Rectifier This unregulated unit had a selenium rectifier that started smelling a bit sweetly, which is the smell of impending failure. I replaced it with a silicon rectifier and also added a short circuit current limiting resistor, as I dunno whether the transformer is short circuit proof.

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