Archive for the ‘Electronic Components’ Category:

2021-02-25 Set Blows Out Substitute Diodes

From FB group I take … Alejandro Cruz He said a diode is a diode but there are more than volts and current. The reverse recovery time is important. If it is rectifying 50 or 60 Hz AC then standard recovery time is good. If it’s rectifying high frequencies then it should be fast recovery

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2021-02-08 IEEE.ORG Website Is Not Private. Intersil ICL 8038 Function Generator

Chrome won’t allow me to connect to the spectrum.ieee.org website because it’s saying it’s not private. I go to learn more and they don’t have any way to override the error message. I went here first to read the story and tried the link at the end to comment. https://spectrum.ieee.org/tech-talk/tech-history/silicon-revolution/decoding-the-innovation-delusion-nurturing-the-maintenance-mindset They asked in an article

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2020-10-29 Freq Counter – Crystal Tester Mod For Low Frequencies

I got this frequency counter and crystal tester mainly for the frequency counter. Today I decided to test a few crystals, and was successful with ones above 10 MHz but not at 4 MHz. The two capacitors labeled C2 and C3 are the feedback to the crystal, and they were originally 22 pF. So I

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2020-09-05 Capacitive Dropper Failures In 240 VAC countries

From a comment I left in Big Clive’s youtube video https://youtu.be/jgaCYRc1-og In the past I’ve seen Clive having to replace “used up” capacitors in the ‘capacitive dropper’ circuits of low cost line operated devices. The problem seems to be common in other countries but here in the US I haven’t seen any problems with the

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2020-06-13 MLCC Replacements For Electrolytic Capacitors

Reply from FB comment Mark French I got a roll (on tape) of 22 uF, 10V and 47 uF, 10V tiny surface mount MLCCs. They’re not polarized, but I’ve heard they tend to be microphonic. I’m going to try leaving the old caps in and bridge a MLCC across them. They’re small enough to to

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2020-06-11 Optocouplers Don’t Always Protect

From FB comment Monty Ross It’s true that optocouplers are used for isolation. But I have seen whole sections of PC boards with a hole burned where the optocouplers used to be. It is incredible how much damage the power lines do to the PC boards due to high voltage spikes in the power. Transformers

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2020-06-01 Motorola HEP Catalog Transistors pp 10-12

These are scans of the specifications for most of the Motorola HEP line of replacement transistors. Germanium and Silicon. Pages 10, 11, 12.

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2020-03-10 Simple AM Band Antenna Tuning Coil 240 Microhenrys

The standard ferrite antenna loopstick for a 365 pF tuning capacitor has an inductance of about 230 microhenrys. This in combination with the tuning capacitor tunes across the full AM broadcast band. It’s useful to be able to wind your own inductor so it can be used for an antenna coil, a trap to attenuate

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2020-02-21

I found that 100 uH was a good all around value for these solar garden light circuits. But at the time I made these around 2009 the 5252 4 legged chip was uncommon and almost all the garden lights used 2 discrete transistors. I don’t know why they started using the 4 legged 5252 –

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LED Indoor Motion Sensing Lights – Decrease On Time

I bought two of these motion sensing LED lights for my hallway. They have a rechargeable cell that is charged through a micro USB port. To see one inside watch big Clive’s YouTube video – the ebay link to buy them is in his description. The charge lasts for more than a week with frequent

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