I use an RDBMS as my *sole* persistent store. As with any "component", I expect it to provide the capabilities that it was designed to deliver...

I use an RDBMS as my *sole* persistent store. As with any "component", I expect it to provide the capabilities that it was designed to deliver (e.g., ACID). [This is a key assumption, thus should be examined carefully] As such, it frees clients from having to check input data (if from the DBMS) as the constraints and triggers on the DBMS ensure that the data is well-behaved without nee...

I have a circuit to replace a 2050 Thyratron tube with a FET and an SCR C106, but I am having trouble sourcing the FET as I am not sure how to...

I have a circuit to replace a 2050 Thyratron tube with a FET and an SCR C106, but I am having trouble sourcing the FET as I am not sure how to translate the only specs on it that I can find to something more modern. It was made by Siliconix # U266 or FN2651. Specs are as follows: ------- https://www.flippers.com/pdfs/Siliconix_RAE_1968_Catalog_Redacted.pdf Igss = 6.0 nA BVgss = 150...

We have a mosfet closed-loop programmable current sink that works fine most of the time but behaves badly at startup from zero current or...

We have a mosfet closed-loop programmable current sink that works fine most of the time but behaves badly at startup from zero current or at very low currents. The fix is to drool in a bit of keepalive current so that the loop never goes open and rails low. https://www.dropbox.com/scl/fi/3ql0ew6a2elh562wbsx96/Keepalive.jpg?rlkey=fujknponcgtf31mi3rf072x 5e&dl=0 The 400 volt MMBD5004 would b

https://www.dropbox.com/scl/fi/40slcbgbngggdcwwt95vi/Relay_Drivers.jpg?rlkey=gfai2trx0n6bnja2yl4 hber7i&raw=1 I like C1, with just a...

https://www.dropbox.com/scl/fi/40slcbgbngggdcwwt95vi/Relay_Drivers.jpg?rlkey=gfai2trx0n6bnja2yl4 hber7i&raw=1 I like C1, with just a high-enough-voltage mosfet that it survives the max flyback voltage. C2 would use some exotic avalanche-rated thing. Everthing else needs more parts. Any more?

Has anyone used filled vias? Epoxy? Copper? I need thermal conductivity, as in a D2PAK on one side of a board and a heat sink on the other.

Has anyone used filled vias? Epoxy? Copper? I need thermal conductivity, as in a D2PAK on one side of a board and a heat sink on the other.

I'm looking for some large (6+ inches dia) spheres that can be machined to suit my needs. They need to have some "heft" and be reasonably...

I'm looking for some large (6+ inches dia) spheres that can be machined to suit my needs. They need to have some "heft" and be reasonably durable (glass would be ideal but hard to "machine" and too fragile -- or, so says my "glass guy") Bowling balls (10-pin) are the obvious idea that comes to mind. But, they aren't homogenous materials (and, I'm not sure I could get information on the...

Anyone hae any additional info? Excerpt from a Register article ( ) The Deep Space Optical Communications (DSOC) experiment will head off...

Anyone hae any additional info? Excerpt from a Register article ( ) The Deep Space Optical Communications (DSOC) experiment will head off into the void with Psyche, an asteroid-chasing probe that is scheduled to blast off on October 5. While they journey toward 16 Psyche, a metal-rich asteroid

I'm going use an insane number of 7x20mm SPST relays, so I'm testing relays and drivers. Here's a...

I'm going use an insane number of 7x20mm SPST relays, so I'm testing relays and drivers. Here's a start. https://www.dropbox.com/scl/fo/ns08x686afbayjsw8c2ab/h?rlkey=m9dr3wdnhd3v6ftdhwga65mzb&dl=0 The waveforms are drain voltage and source current. Two surprises: that little 100 volt logic-level mosfet avalanches happily at just over 100 volts. The drain voltage doesn't ring. Th...

In my ongoing effort to rid myself of "excess kit", I'm now turning my attention to my collection of APs. Is there any reason to hang onto...

In my ongoing effort to rid myself of "excess kit", I'm now turning my attention to my collection of APs. Is there any reason to hang onto anything pre-WiFi 6?

Unshielded drum cores are cheap and have lots of L*I^2 for their size. But they leak mag fields. Maybe I can put two side-by-side and have...

Unshielded drum cores are cheap and have lots of L*I^2 for their size. But they leak mag fields. Maybe I can put two side-by-side and have their far fields mostly cancel. I need two anyhow. Most are 2-pin parts and without a polarity dot, we'd have to test and mark them. Wurth has a 4-pin part with a dot. https://www.mouser.com/ProductDetail/Wurth-Elektronik/7447211101?qs=HXx4m3XcTe...