Daily On/Off circuit?

Started by Terry Pinnell in sci.electronics.design3 days ago 42 replies

My 15 year old 'Garden Lamps Unit' is switched on via an LDR, 4001 Schmitt, 4013 flip-flop and a relay. And switched off by an...

My 15 year old 'Garden Lamps Unit' is switched on via an LDR, 4001 Schmitt, 4013 flip-flop and a relay. And switched off by an ancient mechanical clock closing a contact which delivers a +ve going 12V pulse to the SET pin of the flip-flop, switching off the lamp around 11 pm. (BTW, intuitively I'd have expected that to be called RESET?) But not surprisingly the clock is unreliable, its han...


30 years in prison for Trump

Started by Alan Folmsbee in sci.electronics.design3 days ago 29 replies

Russia has benefitted from the sanctions Trump has imposed on the USA. Putting government workers out of work was "mostly democrats" according...

Russia has benefitted from the sanctions Trump has imposed on the USA. Putting government workers out of work was "mostly democrats" according to Trump. Ruining American culture is hurting mostly democrats, so republican scum support the traitor from the Electoral College.


smart bulbs?

Started by John Larkin in sci.electronics.design3 days ago 10 replies

...

https://www.amazon.com/LOHAS-Equivalent-Automatic-Security-Lighting/dp/B0747QT5WW/ref=sr_1_4?ie= UTF8&qid=1550343306&sr=8-4&keywords=light+bulb+dark+sense If I put two of these in the same fixture, I wonder if they will confuse one another. Probably not. -- John Larkin Highland Technology, Inc lunatic fringe electronics


OT spiders, snakes

Started by John Larkin in sci.electronics.design3 days ago 15 replies

Are you afraid of spiders or snakes? It may be genetic. -- John Larkin Highland Technology, Inc lunatic fringe electronics

Are you afraid of spiders or snakes? It may be genetic. -- John Larkin Highland Technology, Inc lunatic fringe electronics


1/4 oz copper

Started by Winfield Hill in sci.electronics.design4 days ago 32 replies

Anybody ever ordered PCBs with 1/4-oz copper layers? -- Thanks, - Win

Anybody ever ordered PCBs with 1/4-oz copper layers? -- Thanks, - Win


IDC headers

Started by Phil Hobbs in sci.electronics.design4 days ago 4 replies

So a customer wants us to replace a board-mounted D9 connector with a cable assembly, so they can mount our board elsewhere in their box. (So...

So a customer wants us to replace a board-mounted D9 connector with a cable assembly, so they can mount our board elsewhere in their box. (So much of engineering involves the apportioning of pain between individuals and groups.) ;) I naturally looked at IDC connectors--D9 male IDCs are reasonably plentiful, with 30 choices at Digikey with gold contacts. But the other end, i.e. 50-mi...


JTAG header highway robbery

Started by Phil Hobbs in sci.electronics.design4 days ago 34 replies

Hi, all, So we're getting some parts for a small board fab--it's that VCA thing I talked about a week or so back. One of the biggest items...

Hi, all, So we're getting some parts for a small board fab--it's that VCA thing I talked about a week or so back. One of the biggest items in the BOM cost is the standard 10-pin mini JTAG header, Samtec FTSH-105-01-L-DV-K-A-P. It's now up to over four bucks! What do you folks use instead? Thanks Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innova...


attenuator

Started by John Larkin in sci.electronics.design4 days ago 11 replies

...

https://www.amazon.com/Attenuator-3db-Sma-Module-Pack/dp/B07MWD949Z/ref=sr_1_21_sspa?ie=UTF8&qid =1550097003&sr=8-21-spons&keywords=sma+attenuator&psc=1 -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com


glob-top thermals

Started by John Larkin in sci.electronics.design5 days ago 42 replies

I was wondering what might be the thermal effects of lumping a heap of glob-top epoxy on a surface-mount part. I have an interesting...

I was wondering what might be the thermal effects of lumping a heap of glob-top epoxy on a surface-mount part. I have an interesting circuit that unfortunately dumps 0.8 watts into a 1206 resistor. That's pushing things a bit even by my standards. I might be able to push stuff around to fit a 1210 or even something bigger, but not much. The entire board is 0.77 square inches and there...


RF prototypes/ ARRL handbook

Started by George Herold in sci.electronics.design5 days ago 86 replies

Hi all, A (mostly clueless) physics type wants to do some RF stuff. (measuring nmr signals.. protons, ~5-25 MHz range) He's got something...

Hi all, A (mostly clueless) physics type wants to do some RF stuff. (measuring nmr signals.. protons, ~5-25 MHz range) He's got something working, but construction is ugly. I was thinking of recommending an ARRL handbook, is any version better than others?


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