ESR Meter confusion

Can't remember the last time I saw a toumbstoned SMT part from a production, or even prototype production line. Probably at my last job - a small company trying to build on the cheap (RoHS with a three stage oven). I thought toumbstoning was a thing of the distant past.

We had that problem, too, but haven't seen it since I left there. I found it easier to just reheat all connections in the suspect area.

I use them to verify that the correct part was put on the board. Once in a while our CM screws up the SMT program. Backwards SOT23-6s seem to be their big problem.

We sometimes see dry joints in quick-turn boards, especially our last batch from Screaming Circuits--they must have used a specially-thin stencil, because there are no solder fillets at all. We probably had

Cheers

Phil Hobbs

The min and max are on the data sheet too. If they're not, buy something else. At three cents each, may as well but good parts from authorized distributers, so you can be confident that they meet their specs.

If you want a well matched diff pair, buy an opamp. Most dual transistors these days are just two die potted together, not very close and not well thermally coupled.

Yikes! BJTs or mosfets hard in parallel, running in linear mode, are a recipe for endless grief.

They just keep getting better! I don't think I have any circuits that mind more beta. And I prefer mosfets anyhow.

I got some smart tweezers and a vacuum part pickup thing, but don't use them. I do use my AADE l/c meter a lot.

More beta tends to go along with lower breakdown voltage and more capacitance. So it isn't always a benefit, by a lot.

That meter is the only electronics kit I've ever built--in 2015!

Neil was already too sick to assemble them. Poor guy.

Cheers

Phil Hobbs

I used to build Heathkits and sell them at my cost. I just liked building them. It didn't occur to me to make a profit.

He was cool, and it's a great little instrument.

Like I said, repair and manufacture involve different mindsets.

.... Phil