really tiny transistor

Wow! I've got dreams of seeing HBT* correlations. (and then showing others.) I need the right light source, and then fast low noise detectors.... and other stuff.

The fast transistor might be useful as a fast diode. George H.

I'm doing some fast o/e circuits lately, but not especially low noise. My fiberoptic digital links have lots of light. The sugar-cube fiber coupled photodiodes, with TO18 cans inside, have a lot of inductance and capacitance if you bend the leads down into thru-hole pads. So we designed this saddle thing, to make a planar interface to the PC board.

I characterized the late lamented Avago SOT89 phemt as a diode, two ways. It was awesome, a 1 amp, 1 pF, 20 v diode.

These SAV phemts would probably be good diodes, but there's no apparent advantage over a cheaper low-barrier schottky. Possibly lower forward drop at higher currents.

A "grid leak" AM detector might be interesting.

We generally use the card guides in the extrusion, so the nut on the BNC connector is the main mechanical reference. It's sort of an outgrowth of my dead-bug prototyping method, which uses BNC connectors to hold copperclad board against the lid of a die-cast aluminum stomp box.

Cheers

Phil Hobbs

We were going to use the card guides in an extruded box, for my new fast photodetectors, but that led to a spiral of issues that were solved by designing the new box and hard-bolting the board along its edges.

The card guides don't actually do much. They sorta can't. But all the box makers have them.

Maybe we should allow for our box to be eventually converted to an extrusion. The pcb mounting screws would probably have to come in on the top side of the board. I'll talk to Paulo.

What went wrong with them?

They're not ideal in a high-vibration environment, but we like them OK otherwise.

Tell him I said hello. We spent a week in the Azores last summer. (I think he's from there, isn't he?) San Miguel is a beautiful place. The vegetation looks like somebody's garden run amok, with miles-long hedgerows made of blue hydrangeas. We're hoping to go to some of the other islands next time.

Cheers

Phil Hobbs

No good path for cooling. Or any clean way to mount the board. Pem spacers on the board to the bottom of the extrusion is clumsy and takes board space.

Here's Paulo's model:

OK, I will. Yes, Azores.

San Miguel is a beautiful place. The

Just curious, what do you do for feet on the bottom of the box, and how do you keep them from falling off?

We don't. There are some tapped holes on the bottom, so it can be bolted down. We sell a rackmount tray too.

Thanks