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Jake T <jaketbone@steak.com>: Jan 12 02:18PM -0500 On 1/12/22 7:56 AM, Peter W. wrote: > Really? Dumpster Diving for a $0.65 (+ tax) part? And a used one at that?   > Peter Wieck > Melrose Park, PA   I ordered from Digikey via the snail mail system to avoid shipping. Ordered some other goodies too. Where I live, I think I'd be locked up if I tried dumpster diving. They won't pull you over for driving like a jacka** through town, but if they see you taking stuff out of the dumpster, look out!

Guy Patterson <str00ntz@aol.com>: Jan 12 01:06PM -0800 On Wednesday, January 12, 2022 at 7:56:52 AM UTC-5, Peter W. wrote: > Really? Dumpster Diving for a $0.65 (+ tax) part? And a used one at that? > Peter Wieck > Melrose Park, PA   Fair point, but you might find a Faberge egg while you're snorkeling through the offscourings.

Chris Jones <lugnut808@spam.yahoo.com>: Jan 13 10:46PM +1100 On 12/01/2022 23:56, Peter W. wrote: > Really? Dumpster Diving for a $0.65 (+ tax) part? And a used one at that?     I'll happily take a genuine Motorola, National or TI part out of a dumpster and available today, over whatever you might receive in a month's time from a random ebay seller in China (which was the OP's original suggestion). Heck on ebay you might end up with a used part anyway, albeit with carefully straightened pins and a freshly lasered part number on it, perhaps related to its internal circuitry, perhaps not.   If you're building things for yourself, or even prototypes at work where time is of the essence and you don't have the new part you need, there is nothing wrong with testing and reusing the occasional part from scrapped high-quality equipment, (unless you're building pacemakers or satellites, or for production use where you need traceability etc.). Some newly made TO-220s have more bendy thinner tabs to save copper, so I prefer the old ones with the thick tab anyway - less chance of cracking the die when you do up the screw.

Chris Jones <lugnut808@spam.yahoo.com>: Jan 13 10:57PM +1100 On 13/01/2022 06:18, Jake T wrote: > if I tried dumpster diving.  They won't pull you over for driving like a > jacka** through town, but if they see you taking stuff out of the > dumpster, look out!   Pity, though it would save me a lot of problems with storing all the test equipment I find.

lanavy2307 <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1214@example.com>: Jan 13 05:37AM #94-620-01 for a Crate Amplifier.   --

Phil Allison <pallison49@gmail.com>: Jan 12 10:04PM -0800 lanavy2307 wrote:   ======================   > #94-620-01 for a Crate Amplifier.   ** See:   https://www.ebay.com/itm/333707902162?_ul=IL   https://www.banzaimusic.com/transformer-t-pwr-carvbap.html     ...... Phil

whit3rd <whit3rd@gmail.com>: Jan 12 06:59PM -0800 On Tuesday, January 11, 2022 at 5:13:08 AM UTC-8, Jake T wrote: > maybe something that would mute the audio when a certain audio level is > exceeded? Suggestions for such a circuit would be welcome. It would be > placed between the mic output and speaker. Thanks in advance.   There's an integrated circuit, LM13700, that has this basic function. See figure 17 here <https://www.ti.com/lit/ds/symlink/lm13700.pdf>   That example uses one half the chip, and responds to pulling the 'gain control' pin low when the sound is too loud. The tricky part is, you use the other half of the chip to amplify, rectify the sound from AC to negative DC, smooth the DC with a capacitor, and steal some current from the "Iabc" circuit node while that capacitor stays negative. It's just a couple of capacitors, diode, and a lot of fiddling with resistor values.   Alas, it's an oddball chip, and an oddball kind of design.

Chuck <chuck23@dejanews.net>: Jan 12 03:36PM -0600 On Wed, 12 Jan 2022 05:50:21 +1100, Trevor Wilson >mechanism. They are horrible to work on. I refused to take them in for >service many years ago. Just not worth the effort. Carousel types are >much easier. Thanks Trevor. I figured as much. I have years of experience working on Yamaha carousel players but none on this mechanism.

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