An unusual Oscilloscope phenomenon

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It depends on the shield resistance. Putting a 1-ohm resistor between the shield and ground on the Rx end is as good as an open circuit for ground loop purposes, and should get rid of the antenna problem.

Cheers

Phil Hobbs

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But:

We used such transceivers in multi/multi type ham radio contests and field days. There you had to deal with another 100W transmitter blasting into an antenna maybe 100ft away. You could make a light bulb glow on the other antenna. Many transceivers fell off the rocker there, the only ones that always performed were the super-expensive Collins line and the Heathkit at the budget end of the price scale. If their signal management wasn't up to snuff this would never have worked.

All the more money for me. ;-)

Tim

My Heathkit IO-103 scope is the same way.

Tim

Two coaxial shields with one end of each grounded at opposite ends is pretty nice.

Best regards, Spehro Pefhany

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Is that open end shield rather than opened shield, or am I missing something here. Grounding one side is pretty common knowledge, though you get arguments over which side to ground.

Didn't anyone tell you that dovetail joints were optional? :-)

Just kidding. I can't imagine even you would have chiseled out dovetail joints (since I'm thinking those dovetail jigs you use with a router didn't exist for the casual home woodworker back then)...

I built a small table (~2'x2'x1') for test equipment to live on not quite a month ago. I thoroughly enjoyed using a dado blade to cut a bunch of lap joints, and verified the table could hold 300lbs. Old boat anchors, here I come!

Podcast:

Nice, love your accent. If it were winter here, I'd fire up my Tek 547 (since my Rigol is at a friend's). But in summer, the 547 cancels the A/C so I don't use the 547...

I didn't go that far but I polished and stained the corners until you couldn't really see where things butted up anymore.

Saw a contractor commercial lately about the Fein Multimaster. Drooling all over the place. Fein is "the" electric tool company in Germany, only the good stuff. You had to call a 1-800 number to find out the price and that should have been a dead give-away. Well, found it on the Internet, saw the prices of spare inserts and decided that I do not need it this urgently.

That's the other thing I built, or partially had built when I was around

I guess nobody told you about the shims. ;-)

Cheers! Rich

I first saw the Fein Multimaster at the Portland Woodworking Show not that long ago. They were having a grand time demoing it -- and letting anyone who cared to try it out themselves -- and it was *very* tempting.

There's been a lot of competition with it lately (apparently Fein's patent expired?):

Rockwell:

...and there's always eBay for knock-off Fein inserts... (quality level... who knows?)

Nice story about getting your workbench frame built. I suspect that just couldn't be done today, unfortunately. :-(

---Joel

Almost forgot... Bosch has a rechargeable version, but the reviews are mixed:

-- and how they're a very, very good tool...)

Fein is simply crazy expensive. I looked at their routers over the weekend. I wasn't impressed, for 4X what a Bosch or PC costs. Bosch has a "Multi-Master type tool ("Multi-X", I think) that's a lot cheaper and looks just as good (Li-Ion battery, though). A little lower down the line, Dremmel has a copy for $100ish. If you want to go cheap, HarborFreight has one for $40. The reports are decent, acknowledging that it's a $40 tool. The only real complaint is that the blades loosen.

No shims. The trick is to lay the Formica upside down onto the floor, butter it up with glue, then lay the wood piece on top. While doing the latter it slipped my hand and ... thud, landed on the Formica. Almost perfectly line up. With the emphasis on "almost". There was no way to get this off because it was the Henkel Pattex type glue which never lets go of anything.

How do shims fix a skewed veneer?

Alright! Thanks. I guess I do have to check out Harborfreight.

No, the HW store closed. The usual, the 3rd generation drove it into the ground :-(

The $40 version will be good enough for me. I've used Fein drills, they are really top notch. I think grampa's drill in the garage is a Fein. About 100 years old, works like a champ.

Hello:

Since you're into it, why don't you compare the refresh rate of digital vs analog scopes? Also known as the waveforms-per-second capability? It's something i'm very curious about in practice, and also, do the digitals behave as the analogs (like a low-pass filter) when you increase the freq of a wave-form or suddenly start aliasing?

Thank you. I really enjoy your blog

Best Regards Steve Sousa

"Steve Sousa"

Bit later they show you another one.

Bit like tasing a pot of stew with your little finger.

Plain fact is that you do not get to see what is actually coming down the probe cable and you may well see stuff that is not there at all.

Bit of a worry, really.

..... Phil