prepreg question

Doesn’t foil always go on prepreg? Putting it on a fully-cured core would need glue, and wouldn’t interlock with the surface texture.

Cheers

Phil Hobbs (Coming to you from some random patch of ocean, a bit south of Cuba)

Dr Phil Hobbs snipped-for-privacy@electrooptical.net wrote: |----------------------------------------------------------------------| |"(Coming to you from some random patch of ocean, a bit south of Cuba)"| |----------------------------------------------------------------------|

I like satellites! (S.

I guess that stackup is common, foil and prepreg on the outer layers. That looked weird to me. I would have expected three cores and two prepregs.

We were just having a philosophical debate about 6-layer stackups. The decision is

L1 sigs and parts L2 gnd plane L3 sigs L4 sigs L5 power plane L6 sigs and parts

and we have to get the impedances and crosstalk and bypassing right.

Caymins? Or on a ship?

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Space or soviet?

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

I like spacecraft. Many notable space ex-craft used to be from the U.S.S.R. (S.

The Resilient Lady (Virgin). Pretty good ship, and on interline rates you can’t afford not to go. (Keeping the bar bill low, of course.)

Cheers

Phil Hobbs

I spent a month working in the USSR. It was kinda weird.

We'd go into a restaurant and ask for beer, piva. They's say "nyet piva", we don't have beer tonight. No wonder the USSR fell.

They did have Cuban rum in the hard-currency stores. It was pretty good. We couldn't get Havana Club in the USA.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

A while back we could see a ship from our kitchen deck, at anchor in the bay. The crew was quarantined aboard. We called it The Covid Princess.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

And the US is randomly bombing ships in that area?

This is what I like more:

And this is good too:

Thinking about buying a little sail boat and sail away before the war house nut case starts WW3 Need to work on my space-drive !

No safe place on earth left?

Can your Resilient Lady still re-fuel? Or are you stuck forever on Cuba?

I like Mississippi. The weather is awful but the people are nice.

And the Mississippi river is awesome. Take a ride on the Natchez up to Oak Alley if you can.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Yes, nice organ too, must be really loud!

Makes me wonder, are propellers so much better than these wheels?

Don't know. It is interesting.

Here in San Francisco, we have the Jeremiah O'Brien, one of the last Liberty ships still running, a D-day veteran. It's an ancient steam piston engine. The boilers are ancient too, so they run them at something crazy like 200 PSI.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

A stern-wheeler was designed and built for opening up a local weed-clogged canal. It tended to chuck the weeds into the stern of the boat, rather than getting constantly tangled up in them.

It's available for tours and an occasional cruise on the bay.

The radio room is full of original stuff that still works.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

There is still a lot of military surplus radio stuff for sale that actually still works: Dutch site:

But for a few dollars you get a good portable marine band transceiver...

--device-index <index> Select RTL device (default: 0).

--gain <db> Set gain (default: max gain. Use -100 for auto-gain).

--enable-agc> Enable the Automatic Gain Control (default: off).

--freq <hz> Set frequency (default: 1090 Mhz).

--ifile <filename> Read data from file (use '-' for stdin).

--interactive Interactive mode refreshing data on screen.

--interactive-rows <num> Max number of rows in interactive mode (default: 15).

--interactive-ttl <sec> Remove from list if idle for <sec> (default: 60).

--raw Show only messages hex values.

--net Enable networking.

--net-only Enable just networking, no RTL device or file used.

--net-ro-port <port> TCP listening port for raw output (default: 30002).

--net-ri-port <port> TCP listening port for raw input (default: 30001).

--net-http-port <port> HTTP server port (default: 8080).

--net-sbs-port <port> TCP listening port for BaseStation format output (default: 30003).

--no-fix Disable single-bits error correction using CRC.

--no-crc-check Disable messages with broken CRC (discouraged).

--aggressive More CPU for more messages (two bits fixes, ...).

--stats With --ifile print stats at exit. No other output.

--onlyaddr Show only ICAO addresses (testing purposes).

--metric Use metric units (meters, km/h, ...).

--snip <level> Strip IQ file removing samples < level.

--debug <level> Debug mode, see README for more information.

--help Show this help.

Wrote some code for that long ago, still running 24/7:

Those Liberty ships were referred to as "Kaiser's Coffins" by the men in the Merchant Marine during World War II, in reference to Henry J. Kaiser who produced them in an assembly line, often with cement hulls. There used to be one on the beach in Santa Cruz that had split in half when the hull cracked down the middle of the ship.

HJ built a liberty ship per day.

Kaiser made cars for a while too.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Look up "critical crack length in Liberty ships".

The problem was that the hulls were continuously welded structures and there was nothing to stop cracks from propagating across the whole hull in microseconds. The earlier comet aircraft suffered from the same problem. John