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Bob's Mailbox

Hiya Bob:
In case 450,000 people haven't suggested this already, here goes: Our new car (which, alas, is new) keeps the radio playing until you open a door. I like that! (But what if I want to listen with the door open? I don't like that. /rap) A timer isn't a bad idea, but what if you need 10 more seconds to hear whatever it was you wanted to hear? (I just turn on the ignition for another 2 seconds, and the timer runs again. I don't have to wait for it to shut off. I just turn the key momentarily. /rap)

I assume you have a door-activated dome light, as you mention using a door switch for some items. You could build that for your car, too.
via e-mail

Yeah, but I don't WANT a setup like yours. When I get out of my car, I want the radio to keep playing until I get in the house. With your setup, I would have to climb out the window. No, thanks!—RAP

Hi Bob:
Several years ago, I came across a neat little circuit that would flash my motorcycle's main headlamp alternately between low and high four times a second. I thought this little attention getter might give me a tad more visibility. It certainly did. A police officer informed me that only emergency vehicles could have this sort of display. Until your laser hologram becomes available, I'll just treat everyone as though I'm invisible and give 'em (and me) lots of room.
via e-mail

I've seen motorcycles with their headlights blinking away wildly like this. At least in the daytime it ought to be OK. I can't imagine anybody complaining. Check your state traffic laws—the cop might be wrong.—RAP

Dear Mr. Pease
I always enjoy your column, and was amused about the round manhole covers. Here in England, most of them are square or rectangular, and we don't seem to drop them into the manholes!

On another topic: Breadboarding. I use strip board with strips and holes at 0.1-in. spacing. I've found it easier to use it upside down, i.e. soldering the devices into the strip side. At HF, I "super glue" copper foil onto the other side to form a ground plane. It may not be very good above 50 MHz, but it's OK up to there using phenolic-based strip board. I haven't anything so crude as figures to back that up, but things seem to work.

Sorry to hear about your VW Beetle. I've never had one, but they are a cult car here, too. (I'm not a professional, but a Ham Radio man.)
via e-mail

Yeah, there are lots of breadboarding styles. So long as the ground plane is nearby, they work well. My newest (1970) Beetle sure runs strong. And— HA!—it has 10% more trunk space than the New Beetles.—RAP

Dear Bob:
I get so many trade publications I can't possibly ever read them all. Well, anyway, just a note to tell you that no matter how many Tech. Pubs. I get, I ALWAYS seek out your articles for a breath of fresh air. When work is unusually hectic, I can always read one of your columns and bring immediate sense to my day....
via e-mail

Thanks, Mike. Yes, I even go back and read my own stuff, to find out what I wrote! Sometimes it makes a good break from THINKING!—RAP

All for now. / Comments invited!
RAP / Robert A. Pease / Engineer
[email protected]—or:

Mail Stop D2597A
National Semiconductor
P.O. Box 58090
Santa Clara, CA 95052-8090

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