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As a Dayton resident, I agree that Mendelson's can be interesting to wander around. Have the elevator attendant take to to the third floor to browse the electronic components. A lot of the stuff seems overpriced to me, but sometimes you can find a good bargain or obscure component among the junk.

I'll also second the Air Force Museum. If you haven't been in a while, they've opened up a new hanger in the last year or so.

Dayton Hamfest, May of every year, with a trip to Mendlesons.

>>Where do you buy 80 ohm coax? I've heard of 75Ohm, but not 80.

http://www.electrospec.com/alpha/product_detail.asp?item=9840+BK001

http://www.meci.com/product_info.php/products_id/6302327?osCsid=9575d379ece2e7a4a29cd750b9338529

I did mean to say 75 ohm, but I've been working on an 80 ohm dipole antenna lately, so my numbers were mixed up.

-b

• All Electronics usually has good deals on power supplies and DC-DC converters.
• Meci has some great deals on DC-DC converters right now too.
• Electronics Goldmine might have some too.

Perhaps if I come up with some spare change and a bit of free time I'll hack one together. Keep an eye on Hack A Day in the next month. :)

>But you probably won't need the heavy, 8-gauge stuff that's available. Most system that pump out about 150w RMS per channel should have about 12- or 14-gauge on it. Monster Cable's XP line should be more than adequate, and isn't too expensive. Anything more than that, and you should probably be looking at 8-gauge, though.

Very right, but hell, I'll prove it with science before the audiophiles get here.

A little math using our good old friend Ohm's law into an 8-Ohm speaker. To do this we need a table of accepted wire resistances or one hell of an ohm-meter.

IMHO, 18 gauge wire is overkill for 150 watts. Let's see if it is, though!

Assuming your speaker is 10 feet away from the stereo (your room isn't a concert hall, is it?) we calculate loss as such:

6.6 Ohms / 1000 feet = 0.0066 Ohms per foot = 0.066 Ohms in 10 feet.

To push 150 watts through an 8 Ohm load (speaker) we need:

I = (150 / 8) (sqrt) = 4.33 Amps.

Now, to calculate the loss to heat caused by the resistance of the cable:

P = 4.33^2 * 0.066 = 1.24 watts.

Which likely couldn't even muster a measly 1 or 2 degrees temperature change in an 18 AWG 10 ft. heatsink.

Therefore, by using the crappiest SPT-2 lamp cord you can find, you can have a fire-resistant, UL approved sound system that pumps delivers a full 99% of it's power to speakers at 150 watts. And any normal person will find 150 watts of RMS power total overkill for anything but a sub.

BTW: Don't waste your money on gold plated junk unless you live in an area that gets a lot of corrosion. Gold is a poorer conductor than copper, and therefore is a detriment to efficiency.

Personally, though, I try to use 16 gauge cable. 18 gauge tends to be too thin to be durable enough for me. Oh, and I happily push over 250 watts RMS through 16 gauge wire without even the slightest tinge of warmth on the cable.

By the way, lamp cord is usually a lot more flexible and easier to route than that horrible, unapproved crap they call "speaker cable". Which is why it usually costs a little more than the bargain basement stuff, but heck, it's worth it in reduced effort!

One day I'll print this out really nicely and stick it up next to the stereos at Best Buy/FutureShop. :-)

Excess Solutions Lots of parts. Off 101 at Brokaw.

WeirdStuff Warehouse Lots of Sparcs.

Halted / HSC Good components, lasers, motors, some new parts.

Alltronics Used to be retail on Zanker, with jackelope, but it looks like they're just mail order now.

Closed:

Haltek off Shoreline in Mountain View.

J&M Surplus in San Carlos.

RA Enterprises, the best source of motors

Alltronics (retail)

And here are a few non-SV places with websites:

MECI, Inc.

All Electronics

Herbach and Rademan

C&H Sales

--
chahast AT pangaea FOO dhs FOO org
s/FOO/DOT/g

Mendleson's is a great place! Their website is here, but as oter's have mentioned the most fun is going there in person.

//I'm an idiot... This time I included the linkage ;)

Well, you missed the point, but that's OK.

Realize that if you're operating the car correctly (RTFM lately?), you'll pause long enough with the key in the "On" position to observe the function of the dash lights, before starting the car. Motherboards that POST and get on with loading the boot sector in less than a second are not uncommon, as of late.

And Linux, on such specialized, limited machine would boot -fast-. Which means that chances are good that the thing will be at a mid-point in the boot process by the time the box gets killed by the starter.

And don't tell me that you've never switched your car on and listened to the radio/talked to a friend/finished a phone call for a moment before starting it.

But that's not the point, either.

The point is about building a reliable system. I -never- want to be faced with debugging my car's embedded PC during a vacation, just because I got distracted by an attractive girl and missed the window of opportunity for starting the car.

That said:

Even if a cap would solve any of these issues I raised (and I don't think it will, though it will tend to lessen them), the problem is hardly that they're difficult and expensive to come by:

These 100,000 microfarad, 15VDC caps can easily be wired in parallel - and we all know that multiple parallel caps are generally better for current peaks than larger, monolothic caps. At $39.50 per high-current Farad, they're hardly expensive. And the same place has stocked them for many years, making them rather easy to get.

Actually, I hesitate to call these scams - but more on the level of "selling an article to a person that could be had cheaper somewhere else". Let me show you a perfect example:

Look up electric bicycle motor on Ebay. Now, I am going to pick an auction that doesn't "die" until the 28th so that others can see what I mean - I am picking the last one on that list - click here.

Now, look at that picture of the "dual motor" at the bottom - seems pretty cool, huh? Pretty professional, get a little kit and convert your bike to electric. Cost doesn't seem too bad (if you have priced EV bikes before) - heck, "Buy It Now" is only $1.00 over starting bid - so this motor combo, a cheap bike from WalMart or a garage sale, and a cheap gel-cel battery - and I can have my own electric bike for under $200.00!

The motor only cost $93.00...

Now - go here, and on the left hand side select Battlebot Parts - or click here to see them. Now, go down to the fourth item on that page - look familiar?

MECI sells the exact same thing for $40.00! Just above it is the battery you need (actually, you will need two of them for enough amps to go far enough - and really, this isn't the best motor system to use, but might be fun to play around with).

So, here is an example of an eBay seller using their own ignorance against them.

Unfortunately, this seems to be the "way" of our capitalistic society - middlemen, etc everywhere always scamming for a buck. You see this on Ebay a lot - cheesy CDs of "info found no where else" (yeah right, just everywhere on the internet) - these I would take more seriously if they were selling the CDs as "fruits of labor for scouring the Net" - at least then it could be seen as an internet information gathering service thing. You also see it in the multitude of "plans" showing how to build a 100" projection TV with a special lens (but, you do get the lens - nevermind the fact that plans are everywhere to do this, it uses nothing new, and the lens can be had cheaper at the local Walmart).

These guys aren't typically shut down because they do offer a real product, and actually sell it - and people love it!

Another "scam" - I have seen sellers of SDRAM bidding for memory on other auctions - sometimes within hours of their own auctions - for the same type of RAM - they buy the RAM cheap from another auction, then resell it the same day for a profit to other bidders (and typically, for much more money than they could find it for on Pricewatch).

Many times I have wondered if I could pull these same kind of "deals" off - and each time I stop thinking about it, because it just isn't in my "moral fabric" to rip people off - I would rather tell them where to get it cheaper.

I guess that is one reason why I will never own a business - I am too honest for my own "good"...

bleh.

Actually, I hesitate to call these scams - but more on the level of "selling an article to a person that could be had cheaper somewhere else". Let me show you a perfect example:

Look up electric bicycle motor on Ebay. Now, I am going to pick an auction that doesn't "die" until the 28th so that others can see what I mean - I am picking the last one on that list - click here.

Now, look at that picture of the "dual motor" at the bottom - seems pretty cool, huh? Pretty professional, get a little kit and convert your bike to electric. Cost doesn't seem too bad (if you have priced EV bikes before) - heck, "Buy It Now" is only $1.00 over starting bid - so this motor combo, a cheap bike from WalMart or a garage sale, and a cheap gel-cel battery - and I can have my own electric bike for under $200.00!

The motor only cost $93.00...

Now - go here, and on the left hand side select Battlebot Parts - or click here to see them. Now, go down to the fourth item on that page - look familiar?

MECI sells the exact same thing for $40.00! Just above it is the battery you need (actually, you will need two of them for enough amps to go far enough - and really, this isn't the best motor system to use, but might be fun to play around with).

So, here is an example of an eBay seller using their own ignorance against them.

Unfortunately, this seems to be the "way" of our capitalistic society - middlemen, etc everywhere always scamming for a buck. You see this on Ebay a lot - cheesy CDs of "info found no where else" (yeah right, just everywhere on the internet) - these I would take more seriously if they were selling the CDs as "fruits of labor for scouring the Net" - at least then it could be seen as an internet information gathering service thing. You also see it in the multitude of "plans" showing how to build a 100" projection TV with a special lens (but, you do get the lens - nevermind the fact that plans are everywhere to do this, it uses nothing new, and the lens can be had cheaper at the local Walmart).

These guys aren't typically shut down because they do offer a real product, and actually sell it - and people love it!

Another "scam" - I have seen sellers of SDRAM bidding for memory on other auctions - sometimes within hours of their own auctions - for the same type of RAM - they buy the RAM cheap from another auction, then resell it the same day for a profit to other bidders (and typically, for much more money than they could find it for on Pricewatch).

Many times I have wondered if I could pull these same kind of "deals" off - and each time I stop thinking about it, because it just isn't in my "moral fabric" to rip people off - I would rather tell them where to get it cheaper.

I guess that is one reason why I will never own a business - I am too honest for my own "good"...

bleh.

The place that you are referring to is very likely Mendelson's Electronics. They are located in downtown Dayton, Ohio, and you can also buy things over the 'net. I've been there a few times. I usually just buy wire since it's so cheap; but they have everything from computer racks to water pumps to restaurant tables. Some people call a lot of it junk. Your mileage may vary.

There is just such a store in Dayton, OH. It's called Mendleson's Electronics Co. They also go by MECI. The retail store is two big warehouse floors open to the public. It is a mix of electrical, electronic, store and restaurant fixtures, office furniture, and everything else. You WILL spend all day if you go there.

They also have an online store at http://www.meci.com/.

Josh