EEVblog 1525 - Commisioned Mailbag

[EEVblog]

00:00 - Comissioned component artwork
https://www.bad-dog-designs.co.uk/
01:48 - 1.3GHz DIY FET probe
https://hackaday.io/project/184924-diy-13-ghz-fet-probe
https://github.com/makerprobe/FETProbe_tiny
07:53 - The uSupply makes an apperance!
09:14 - Ron Demcko sends in some goodies

14:23 - Mysterious Patent
19:10 - USB Power Injector Crowd Supply kit
https://www.crowdsupply.com/board-outline
21:25 - Elimo Engineering electronic business card
https://elimo.io/
23:29 - Ambit Infusion Pump Teardown
30:20 - Metrawatt M2037 Multimeter Teardown

[golden_labels]

The capacitors reel should bear the “inhalation hazard” warning! During the middle ages, people were disputing how many devils can dance on the head of a pin. This is 2023 and the question should be brought back: how many bacteria cells can fit on a single SMD capacitor?

I wonder, who is the target industry for such small sizes. SoC with ceramic substrates?

[Kleinstein]

Maxim did quite a lot ADC chips for the early DMMs (ICL71xx variants). Chances are they were 2nd source for intersil and they also had some extra ones for higher resolution. They also have newer ones, including some based on sigma-delta. 

Because of the age I doubt this would be a sigma delta, more like a dual slope or kind of simple multi-slope (like the old LD120 and related). For a classic dual slope I am missing the usually relatively bulky integration cap (e.g. 100-500 nF PP type). There are 3 foil capacitors around, but they look a bit small for an ICL7135 or similar, clould still work for a faster running one (e.g. similar to max132)  to get a fast bar graph.

The relays in the DMM are likely for the current ranges, maybe for the highest voltage (e.g. >200 V). Chances are the set of diodes and transistors are for driving the coils for the relays.

[8086]

The business card is an electronic die, a tic-tac-toe game, and a Simon game  Selectable using the power/mode button.

https://elimo.io/ttt