Archive for the ‘Electronic Components’ Category:

2019-07-08 BigClive Fixes LED Floodlight With Solder

from YouTube video bigclivedotcom about fixing a LED floodlight. Half of the 100 LEDs went dark; he resoldered the LEDs and they all started working. The non-conducting half was not using its half of the 25 mA, so the conducting half was probably running at nearly twice its normal current, or about 25 mA. Hopefully

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2019-07-06 Earliest Audio Amplifiers I built

from FB group Building Transistor Radios July 6 Bill Korbak The early germanium alloy transistors didn’t have enough bandwidth for RF, they were only good for audio. That’s where I built my first amplifier, a three transistor audio amp on a PC board I etched in ferric chloride. I also built the power amplifier. It

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2019-06-14 300 And 500 Telephone Set Networks

From FB group Bell Telephone … June 17 Dan Bottoms I’ve opened up the network of a 500 set, and got my hands full of that bazillion centistokes (like tar!!) clear silicone snot that is inside. I think it finally ran off after leaving it out in the hot sun for a week. I knew

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2019-06-12 Plug-in Coils Pros And Cons

from FB group Regenerative Radio… Jun 13 I’ve thought about using plug-in coils, but I’ve had experience with Grid dip meters and there are a few important issues that must be dealt with. One is, what happens to the unused coils when the equipment is not in use. They get separated from the equipment and

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2019-06-11 Selenium Rectifier Burned Up, How To Replace

from FB group Vintage Transistor Radios Jun 12 Bob Kirsch has the right idea, but the single replacement diode *must* be rated for 400 V peak inverse voltage or more. A 1N4007 is cheap and readily available. I assume you’re in a country where the AC line voltage is 120 VAC, because the rectified DC

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2019-06-06 1/2 Price Offer For Lot Of NOS Capacitors

Posted to FB group Building Transistor Radios Jun 15 Months ago I started watching an eBay item of a lot of twenty Hammarlund 3 to 15 pF air variable silver plated ceramic trimmer capacitors. They were made in 1956, NOS / NIB, sealed in their original packaging and individually boxed. For months the seller wanted

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2019-04-08 Output Transformers Construction

from FB group Regenerative Receiver… Apr 8 庄议翔 The power transformers have the laminations interleaved. The first lamination has an E then I, the next one has I then E. So the transformer core does not have any air gaps, because it does not have any DC flowing through the windings. The transformers for single

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2019-03-31

from FB group Vintage transistor Radios April 3 Are all ‘polyvaricon’ tuning capacitors the same? They’re all about the same size. Charles Vesser Japan Industry Standard… The few that I have examined were 140 pF antenna and about 70 pF oscillator. In parallel give 210 pF. They’re probably made to match up with the loopstick

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2019-03-17

From FB group Building Transistor Radios 2019-03-19 John Ferguson Yeah, I used to use the Sylvania ECG and the NTE catalogs to cross-reference transistors. But then I got some better product manuals from the makers, especially Motorola and National Semi. And I got hold of the professional industry documents. ECG and NTE give a ‘one

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2019-03-15 The Tape Recorder 6V6 Making Crackling Noise

from FB group Building Transistor Radios Tuck Choy I was a reel to reel tape recorder fanatic when I was a kid, and had a recorder with a 6V6 output to the spkr. The first thing I did was modify the recorder to add an external spkr. One time I plugged in a clip leads

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