Search found 1781 matches

by Externet
Thu Jan 04, 2018 5:53 pm
Forum: General Discussion
Topic: Nuts & Volts issues...
Replies: 2
Views: 1775

Nuts & Volts issues...

Is there a place showing the contents of the other years ?

----> http://gramlich.net/projects/nuts_and_v ... index.html

When was the first issue ? Eighty something ?
by Externet
Wed Jan 03, 2018 8:01 am
Forum: General Discussion
Topic: Very unusual desoldering method...
Replies: 9
Views: 2515

Re: Very unusual desoldering method...

Hi haklesup. The lamp bulb used on the video is a common automotive halogen 12V incandescent headlamp bulb, typically 55 to 65 Watts. One filament has a Graves shield to direct the emission towards one side (or block certain direction). There is also 120VAC halogen bulbs (without the shield) that co...
by Externet
Tue Jan 02, 2018 5:48 pm
Forum: General Discussion
Topic: Laptop charger voltage...
Replies: 1
Views: 1551

Laptop charger voltage...

At the beginning, the laptop battery packs were over 14V and the chargers about 18V-19V. Understandable. Now, some laptop packs are 11V, and still use the higher supply to charge them. Why ? Why a 12V nominal automobile 'outlet' cannot directly supply/charge a 11V laptop ? ----> https://www.amazon.c...
by Externet
Tue Jan 02, 2018 5:07 pm
Forum: General Discussion
Topic: True green 'neon' pilot bulbs...
Replies: 3
Views: 1691

True green 'neon' pilot bulbs...

Cannot find them on the market. Do you know of a source ? The ones I see now are red Ne-2 type under a green lens. One uses a powder behind the glass : ----> https://www.aliexpress.com/item/20pcs-Green-5mm-Indicator-Neon-Light-Sign-5X13mm-NeonLight-With-Resistance-for-220V-Verde-NEON-GLOW/3281119278...
by Externet
Tue Jan 02, 2018 12:52 pm
Forum: General Discussion
Topic: Very unusual desoldering method...
Replies: 9
Views: 2515

Re: Very unusual desoldering method...

A piece of sheet metal as half shroud should take care of the glare for the user. Headlamps were limited by law to 55 Watts, but that was a looong ago.
by Externet
Sun Dec 31, 2017 6:58 pm
Forum: General Discussion
Topic: Very unusual desoldering method...
Replies: 9
Views: 2515

Very unusual desoldering method...

:grin: Hi fellows. Have to share this; worth trying. Come back with your observations, results, comments, adaptations, improvements. Am sorry it has some advertisements embedded... Get your finest tweezers ready, it is a very nice way to harvest valuable parts from discarded equipment, enjoy : :idea...
by Externet
Wed Dec 13, 2017 3:39 pm
Forum: Up For Grabs
Topic: Wanted : electret condenser microphone capsules...
Replies: 10
Views: 2410

Re: Wanted : electret condenser microphone capsules...

Electrets arrived from China last week. As expected, not vented, another idiot vendor and the typical ignorant advertising.
Am drilling the ones I have for the project. Done. Erase the blackboard...
by Externet
Sun Dec 03, 2017 6:22 am
Forum: General Discussion
Topic: unmarked transformer
Replies: 8
Views: 2070

Re: unmarked transformer

Very unlikely the blues are related to the reds. Prove by probing for continuity between them. They should not.
The blues should provide power for yielding 5VDC circuitry, the center-tapped 12-0-12 for around 24VDC. Any can be used alone, leave the other disconnected if not needed.
by Externet
Sat Dec 02, 2017 5:47 am
Forum: General Discussion
Topic: unmarked transformer
Replies: 8
Views: 2070

Re: unmarked transformer

Measure the voltage at the blue wires the same way you did finding 12-0-12 at the reds. If there is voltage, is another secondary winding for other voltage uses. If no voltage; unplug and measure resistance. If zero ohms, it could be a thermal fuse. If open, may be an open thermal fuse. A transforme...
by Externet
Mon Nov 20, 2017 11:34 am
Forum: Up For Grabs
Topic: Wanted : electret condenser microphone capsules...
Replies: 10
Views: 2410

Re: Wanted : electret condenser microphone capsules...

Do not care about directionality, but the noise cancelling feature does not bother to have.
Building scuba intercoms and pressure at depth would burst the electret film if not vented...
by Externet
Mon Nov 20, 2017 7:40 am
Forum: Up For Grabs
Topic: Wanted : electret condenser microphone capsules...
Replies: 10
Views: 2410

Re: Wanted : electret condenser microphone capsules...

:x Have about 2 dozen from canibalized gadgets and telephones of all sorts, none is vented :cry: Drilled low the sides of one carefully with 0.40mm holes and still works, seems I did not break anything inside, but unsure the plastic spacer inside got drilled all the way trough. One more week to see ...
by Externet
Sun Nov 19, 2017 5:14 pm
Forum: Up For Grabs
Topic: Wanted : electret condenser microphone capsules...
Replies: 10
Views: 2410

Re: Wanted : electret condenser microphone capsules...

Thanks, Tzap. The venting is at the connection side. Yours show the perforations at the sound side. Ordered some but coming from a chinese vendor is a roulette; if they ship exactly what they show pictured or whatever they want. I do not think they know what they are selling. Should be here in a wee...
by Externet
Fri Nov 10, 2017 1:48 pm
Forum: Up For Grabs
Topic: Wanted : electret condenser microphone capsules...
Replies: 10
Views: 2410

Wanted : electret condenser microphone capsules...

Hi all. Please check behind your spider webs for any vented electrets. Typical 9.5mm size or low profile; with or without pins/leads.

They look like :
Vented.jpg
vented2.jpg
vented3.png
vented3.png (64.69 KiB) Viewed 1808 times
Miguel
by Externet
Wed Nov 08, 2017 2:02 pm
Forum: General Discussion
Topic: Microwave oven transformer... reversed.
Replies: 10
Views: 3638

Re: Microwave oven transformer... reversed.

Thank you gentlemen. Good to learn from your experiences. So about a Volt per turn to expect... With a few fatty AWG turns, a substantial battery charger/eliminator could also be implemented. I wonder if with the primary energized and not loading the secondary there is some things needed to consider.
by Externet
Wed Oct 04, 2017 8:43 am
Forum: General Discussion
Topic: Temperature sensor opinions!
Replies: 15
Views: 2636

Re: Temperature sensor opinions!

Hello Len. Trying to contribute with my grain of sand, I always encounter this doubt when people addresses thermostats... Your "The critical temperature for all points is 40C" ---> means that is the maximum or minimum you want to achieve ? temperature should be controlled from above or under 40C ? G...