Microscopy Lamp for LOMO Microscopes

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One of my LOMO microscopes came with a LOMO OI-35 (ЛОМО ОИ-35) illuminator, the other just with a mirror for an external light such as theLOMO OI-19 (ЛОМО ОИ-19). So I figured to machine myself a light fixture for a 3W LED light. Lamp fixture I did not do any drawings for this and just figured everything out while machining it. I then spray painted the lamp fixture white and added a LEE diffuser filter.

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Audio Isolation Transformer

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The Intimo 5430 tube radio I recently restored has a DIN-5 for an external playback or recording device. So I figured to build an adapter, such that I can hook the radio up to a computer audio output. The schematic itself is fairly quite straight forward. The diodes are 1N4007 and are primarily designed to absorb any high voltage pulse that may couple through the transformer if something goes wrong in the radio.

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Fixing a Soviet Space heater Луч

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I recently got this old 1.2kW soviet made space heater of type “Луч”. The heating resistors/spirals are fine, but the fan was making loud noises. This usually indicates a bad bearing somewhere. Furthermore the heater had a unearthed East-German/Soviet type Schutzkontaktstecker compatible plug, which I was going to swap out to an earthed plug (and also a respective line cable with earth wire). The inner workings are fairly simple: There is a thermal cutoff, then a rotary switch selects which of the heating spirals get supplied and also powers the synchronous motor.

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Microscopy Insights #7

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Pictures taken with a Sony SLT-a37 on my MBS-10 (МБС-10) with the МФУ tube. Porous Concrete Exploded X2 Class Capacitor This capacitor was from my HP 8112A pulse generator, it had a catastrophic failure. I removed it and replaced it with a new one, the pulse generator is working again, albeit it is still somewhat stinky. Moth An unspecified type of moth, I’m not quite sure about the species. Anyone any idea?

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Funkwerk Erfurt 8600a Stelltrafo

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I recently got this east German Funkwerk Erfurt Stelltransformator 8600a, which is a 250VA step transformer with 14 steps and a ratio display. Picture taken after the fixes outlined in this article First thing I saw broken was the plug. The original one out of bakelite broke in an unrepairable manner. I replaced it with another bakelite plug I had sitting around. Cleaning the inside In order to cleanup the inside I completely disassembled and reassembled the unit.

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Magnetic Stirrer Maintenance

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I recently got this magnetic stirrer labeled “Fisherbrand Agitateur Magnétique 10510”. It had remains of silicone on the top. It had some problems with the motor starting at low speeds, so I figured let’s check it out and try to fix it. The circuit is unimpressive, it’s a small transformer, discrete bridge rectifier and a BD681 NPN transistor controlled by a potentiometer to regulate the motor speed. However the advantage here being, that is super simple to troubleshoot and repair.

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Quick Restoration: Theatrical Light

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I recently acquired this rusty theatrical spot light. It looked like, someone already repainted the thing at some point and as can be clearly seen on the second picture above evidently someone put a bulb of a too high wattage in it. I removed the remains of the paint and applied new high-temperature paint. The fixture uses a GY9.5 socket, which in by itself does not really help in figuring out the rating of the light.

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Mettler K7T

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My other laboratory scales and balances: Mettler B5, Mettler P1210, Sauter L10 I recently obtained this Mettler K7T laboratory scale from the late 1950s to early 1960s. It has a resolution of 100mg with a capacity of 800g. Cleaning The internal mirror was fairly dirty, so I gave it a clean with isopropanol. The case didn’t actually have any normal rust spots, this looks more like some corrosive chemical spilled onto there at some point.

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