MightyOhm » Electronics

Surplus Summit 2012 Part Two: San Diego

Jeff — Mon, 20 Feb 2012 15:19:36 +0000

Continued from Surplus Summit Part One: Los Angeles.

After visiting Los Angeles for the weekend, I spent the next couple days in San Diego. I had a chance to visit some old San Diego landmarks as well as one newcomer to the surplus electronics scene.

Surplus Depot, San Diego, CA

Surplus Depot used to be located around the corner from their present location, back when they were called Industrial Liquidators. The store has shrunk a bit but still has some good deals and interesting parts.

More pics!

SD Electronic Supply, San Diego, CA

SD Electronic Supply opened last year(?) and recently moved to a new location just down the street from where Gateway Electronics used to be. I think a lot of the inventory is from the old Gateway store. The owner is friendly and there are a LOT of components available.

More pics!

California Electronic and Industrial Supply, El Cajon, CA

California Electronic Supply has been around for years and is still selling components and surplus stuff. I usually stop by on the way to Murphy’s, below.

More pics!

Murphy’s Surplus Warehouse, El Cajon, CA

Murphy’s has also been an El Cajon landmark for many years. They specialize in surplus military radios but have piles of test equipment, motors, switches, and other stuff. I came here at least once a month when I lived in San Diego.

More pics!

Fun fact: Jerry Mouser of Mouser Electronics started Mouser while he was teaching high school physics in El Cajon! Apparently Murphy was one of his students.

As I mentioned in my last post, these and many more surplus electronics stores are listed on the Surplus Electronics wiki page. If you know of a surplus store in your area, please add it to the list and let’s help keep electronics surplus alive!

Surplus Summit 2012 Part One: Los Angeles

Jeff — Fri, 17 Feb 2012 15:35:40 +0000

(Photo: Tony KC6QHP testing out his 47GHz amateur radio. Remember this post? All that work paid off, the radio works!)

Last month I cashed in some airline miles and finally got to visit some old friends and spend some time in beautiful Southern California. Some long-time readers of the blog may remember the last time I did something like this in 2009.

While I was there I visited my good friend Tony in Los Angeles, and we went on a tour of surplus electronics and swap meets that we called Surplus Summit 2012.

All of the surplus stores mentioned here are listed on the Surplus Electronics wiki page, which is continually being updated and expanded. (Do you know of a place to find surplus electronics in your area? Add it to the wiki!)

If you want to see more scenes from Surplus Summit 2012, there are lots more photos from my trip on flickr.

Here are a few highlights from our tour:

C&H Surplus, Duarte, CA

C&H is the best surplus electronics store I have visited since The Black Hole in Los Alamos. Test equipment, weird scientific stuff, motors, gears, components, the works. The owner, Rick, is a nice guy with a good sense of humor. This place is awesome and a well worth a visit.

(Note: C&H is only open Thursday-Saturday.)

More pics!

W6TRW Swap Meet, Redondo Beach, CA

This swap meet has been around forever is held on the last Saturday of every month, rain or shine, even if that Saturday falls on Christmas, etc. Get there early, the swap was hopping by 8AM.

This is an amateur radio swap meet but there is lots of computer stuff (too much!) and general electronics.

More pics!

All Electronics, Van Nuys, CA

Not that many people realize that All Electronics has an actual retail store in Van Nuys. It’s small but fun to visit. Not everything in the catalog is out on the shelves, but there are also some big things that probably won’t ever make it in the catalog.

More pics!

APEX Electronics, Sun Valley, CA

I visited Apex in 2009. Lots of stuff, much of it junk, but there a few interesting odds and ends. I hear that these guys supply the film industry with a lot of props.

More pics!

That’s it for LA. Stay tuned for Surplus Summit Part Two: San Diego next week!

A glimpse at Electronics Workbenches around the world…

Jeff — Tue, 24 Jan 2012 21:45:00 +0000

Since creating the Electronics Workbench Flickr group last November, I have received lots and lots of really amazing submissions from electronics hobbyists and professionals around the world.

My two biggest takeaways so far? I do not own nearly enough test equipment, and my shop is not nearly as well-organized or space-efficient as it could be (I need to use all available wall space and build up).

Here are a few of my favorite images from the group:

Click any of these images for a larger version!

Joe Grand (of Prototype This! and Grand Idea Studio) and his awesome electronics workshop:

(Nice scope, Joe!)

blalor turned his BMW into a temporary workshop, and his passenger seat is the electronics workbench (note the laptop perched on the dash):

eschlaep (Eric Schlaepfer of tubetime.us) submitted this moody shot of a CRT project in progress:

Senke2 has a nice home lab with a lofty feel:

Looks like *someone* has a Tektronix fetish. Beautiful setup by Alan (W2AEW):

More scope envy, of both the oscillo- and micro- kinds (Thanks Mgburr!):

embeddederic sent in this picture of his workbench. Note the Tek 491 spectrum analyzer up top, 10MHz – 12GHz with 1950s(?) technology:

And lastly, check out this awesome workbench panorama by anachrocomputer (best viewed large):

See if you can spot the Tektronix 575 curve tracer!

There are lots more great photos in the group photo pool.

Do you have an electronics workbench that you’re proud of? Snap a photo and share it with the group!

New Flickr Group for your Electronics Workbench

New Flickr Group for your Electronics Workbench

Jeff — Sat, 19 Nov 2011 00:03:44 +0000

Ahh, the electronics workbench – shrine to the electron, the diode, the transistor, the soldering pencil and flux pen.

You can learn a lot about someone by looking at their workspace. Note the way that they store components (in pullout drawers or plastic organizers?), hang test leads (on hooks or wire racks, or on a nail?), and keep spools of wire at the ready for repairs and new projects.

A look at someone’s electronics workbench gives you a small glimpse into what is usually a fairly personal space – a space where visions become reality and electronics projects are brought to life.

While there are quite a few electronics workbenches on flickr, I determined after a quick search that there had been no attempt to bring all of these glimpses into a hobbyist or engineer’s soul together into one place.

And thus was born the Electronics Workbench flickr group:

Have a photo of your bench? Add it to the group!

No? Then go downstairs into your basement, out into your garage, or up into the attic and take one!

And don’t spend too much time cleaning it up first – noone will believe you that your workbench is that clean when we’re not looking.

Also, a shoutout: This group was inspired in part by the Workbench of the Week (WOTW) page over at The Amp Hour. I don’t think WOTW has been a feature on the show for several months. Maybe we can get Chris and Dave to bring it back??

Happy soldering!

- Jeff

www.flickr.com

SurplusGizmos

Jeff — Fri, 18 Feb 2011 05:04:59 +0000

While I was visiting Portland last month, I made a quick stop at SurplusGizmos in Hillsboro.

SurplusGizmos is what an electronics store should be, and it’s the kind of place that I love to visit. It’s also the kind of electronics store that is completely nonexistant in Austin (oh, my beloved HSC, how I miss you), but I digress…

You can usually tell a good surplus electronics store by the pile of junk outside the door (usually with a sign on it that says “Make Offer.” I’m not kidding:

Inside SurplusGizmos, you’ll find aisles full of electronic components like resistors, capacitors, connectors, random semiconductors, fans, motors, and miscellaneous surplus stuff. Paradise!

AVR microcontrollers! Forrest Mims books!

They have cabinets with drawers full of electrolytic capacitors! Yes! This is what a real electronics store is like!

This way, resistors by the foot!! This ain’t no Radio Shack!

Aluminum by the pound!

Interesting pieces of surplus equipment sold for pennies on the dollar!

They have a huge selection of “solder samples”, printed circuit boards that are used to…

Actually, I’m sure what they are for. I think they are used by the PCB manufacturer to test their process, but can someone comment about what solder samples are for, and why you always get one or two when you order a full panel of PCBs?

Anyway, there were LOTS of them. Hundreds. Looking at these panels reminded me of Dave Jones’ PCB Design for Manufacture video. Lots of examples of v-scoring, tab-routing, fiducials, etc.

I picked up a few to use as coasters/wall art/whatever.

Apparently SurplusGizmos has some deal with Oregon Scientific and gets customer returns of their weather monitoring equipment. It seemed like if you spent the time to collect all the right parts, you could build a complete indoor/outdoor wireless weather station for a fraction of the new cost.

I wish I could have spent more time there, but my time was limited and my luggage space was small. Next time!

If you’re ever in the Portland area and want to see what a “real” electronics store is like – check this place out.

I took lots more photos, many of which are available on Flickr.

Oh, and SurplusGizmos is listed on the surplus electronics wiki. If there’s a good electronics store in your area and it’s not on the wiki, add it! Help keep these small, independently-owned electronics shops alive!

Surplus Electronics Wiki Growing Fast

Jeff — Wed, 07 Apr 2010 20:33:06 +0000

The past few weeks have seen a lot of activity on the MightyOhm Wiki!

Since it was mentioned on the Make: blog last week, helpful readers have been making significant contributions every day.

One highlight of the wiki is the Surplus Electronics Resources page, which I first posted about in February. It has more than quadrupled in size since then and now includes surplus shops in the United Kingdom and Canada in addition to dozens in the United States. If you haven’t seen this page yet, you should definitely check it out.

If you don’t see your favorite electronics surplus store on the list, please add it! Several of these “junk shops” close every year due to rising rents and competition online. Anything we can do to keep them in business will benefit the maker community. One way to do this is by making sure that folks know that these resources exist, and this is where I hope the wiki will help.

I want to express my sincere gratitude to everyone who has been contributing to the wiki. In particular, thanks for making it one of the best directories of electronics surplus stores on the web!

Photos of The Black Hole

Jeff — Tue, 02 Mar 2010 16:12:36 +0000

Last May, my brother and I went on a week-long roadtrip across the US. Ambling down the highway in a very large moving truck, we travelled from California to Texas by way of Tuscon, Socorro, Albuquerque, Santa Fe, Los Alamos, and quite a few rest stops, gas stations, and fast food restaurants in between.

Intoxicated by the chile verde, we spent considerable time in New Mexico, a state that neither of us had visited before. One of the highlights of our visit to the Land of Enchantment was a side trip to Los Alamos, birthplace of the atomic bomb and home of two major attractions for any electronics geek:

Los Alamos National Labs

Sadly, armed guards prevented us from taking a close look at the Los Alamos National Labs. Actually, the museum is pretty decent, and includes scale models of Fat Man and Little Boy, some exhibits about radioactivity and nuclear weapons, and a short film about the history of the labs.

The Black Hole

The Los Alamos Sales Company, aka The Black Hole, is a surplus store started in 1951 by the late ‘Atomic’ Ed Grothus, a former LANL machinist turned peace activist.

I have never seen a more fascinating collection of electronic test equipment, laboratory glassware, chunks of machined aluminum, LN2 dewars, bell jars, dusty old databooks, and just plain weird stuff. Good news: most of it is for sale, although there are very few price tags around and some items are probably in the “if you have to ask…” category.

A controversial Los Alamos institution, it has even been the subject of a documentary, although I haven’t managed to track down a copy (yet).

Here are some photos to give you a taste of what it’s like to wander around The Black Hole:

A geiger counter near the front door clicks away in response to some radioactive source nearby.

One of several aisles of surplus test equipment. You name it, it’s here.

Mmm… Organic Plutonium!

Anadex CF-300R Timer with gorgeous nixie display.

Racks of vintage test equipment. Scopes, counters, power supplies, etc.

Period datasheet for the Fairchild uA741 operational amplifier.

Pan Am hard hat.

Oscilloscope with permanently attached scope camera. This is the same setup you see in the pictures of atomic bomb test shacks in books such as How To Photograph an Atomic Bomb, by Peter Kuran.

Honestly, the pictures capture only 1% of what you’ll find here – you have to actually visit to appreciate this place. Oh, and budget an hour or two minimum. If you enjoy looking at dual trace oscilloscopes and dusty cold war relics as much as I do, you’ll need an afternoon to really do it justice. If you want to see more, check out my Bradbury Science Museum and The Black Hole albums on Flickr.

By the way, The Black Hole is listed on the Surplus Electronics page of the MightyOhm Wiki. Is there a surplus electronics store in your city? Add it to the wiki!

Announcing the MightyOhm.com Wiki

Jeff — Tue, 02 Feb 2010 17:59:53 +0000

I am pleased to announce that the MightyOhm Wiki is now online and open to the public.

While there isn’t a ton of content yet, my hope is that the wiki will become a useful means to share information and resources relevant to the site. At the moment, there are pages for electronics vendors, hardware/software tools, and PCB manufacturers.

Another page I have been working on for a while is the surplus directory, which lists surplus electronics stores around the country. If you have a favorite surplus goldmine in your area, please create an account and add it to the wiki!

MightyOhm Has a Wiki. Check it out.

Kit Building Party Photos & Video

Jeff — Mon, 02 Nov 2009 19:07:43 +0000

This weekend I hosted a post-Halloween kit building party at MightyOhm HQ.

Nine close friends built Conway’s Game of Life kits from Adafruit Industries. This is my favorite kit for these kinds of workshops because it’s easy for beginners to complete in about 2 hours, and when everyone is done, you can wire all of the kits together to create one large cellular automata display. The last time I helped people build this kit was at a Make:SF workshop at the TechShop in Menlo Park.

Here’s a timelapse video of the afternoon, shot with a Logitech QuickCam Vision Pro webcam on an Eee PC 4G running Booru Webcam 2.0.

The capture interval was 5 seconds. I used Quicktime Pro to stitch the images together at 15fps and iMovie to add titles and music (Turbo Outrun by FRP from remix.kwed.org.)

I wore my Halloween costume for most of the afternoon. What am I? Most people on the streets of San Francisco had no idea…

Safety first!

Stuart was the first to finish his kit:

Soldering the kits together to form the matrix:

Nine happy kit-builders with the 3×3 matrix they created with their finished kits:

And lastly, a video of the 3×3 matrix in action:

Three people had little to no soldering experience at the beginning of the afternoon. Everyone who came went home with a working kit. Success!

Improvements to my microscope setup for SMT work

Jeff — Mon, 26 Oct 2009 19:56:19 +0000

Why do I need a microscope for SMT?

The single biggest challenge to doing “real” SMT work (0805 or smaller components and fine lead pitch ICs) at home is being able to actually see what you are doing. I know that there are many hobbyists (and maybe even some budget-conscious professionals) who will disagree with me, but I wouldn’t dream of working with surface mount components without using a microscope. I’ve tried many alternatives, including a 10X handheld triplet loupe, a magnifier ring light, even a nausea-inducing magnifying visor, and none of these even come close.

In case I haven’t made myself clear: I would rather solder SMT’s with a 150W soldering gun than with anything other than a decent stereo microscope.

In January of this year, I scored a stereo zoom microscope on eBay. While my scope is far from state of the art (it’s a “vintage” American Optical model 569) the optics are fantastic and it quickly became the most prized piece of equipment in my shop. Here’s a photo of the scope shortly after I added it to my lab, for more photos and information about it, see my original post.

For the first few months, I used the scope pretty much as it arrived. One of the first major tasks I used it for was assembling the first batch of AVR HV Rescue Shields, and for this purpose it worked extremely well. However, as time went on, it became clear that I needed to improve my setup in a couple areas:

The magnification range of 7-30X was great for working on a few tightly grouped 0805 or smaller components, but was too high for general PCB work. A typical BGA package was larger than the field of view.
The included incandescent projector-style illuminator (shown piggybacked on the scope in the photo above) could only be placed in a limited set of positions and did not have adjustable focus – it made a nice, bright spot in the center of the image that didn’t fully illuminate the field at low zoom levels. While it is removable from the scope (this provides a workaround for these issues), the included stand took up too much bench space to be practical.

Upgrading the microscope:

The first upgrade I made was to add a secondary objective aka barlow lens to the scope. A secondary objective serves to increase or decrease the total magnification of a microscope, while simultaneously trading off working distance, the distance between the bottom of the microscope and an object in focus on the bench. In my case, I added a 0.5x secondary objective, which gave me half the magnification while increasing my working distance by approximately 2x. While American Optical stopped making accessories for the StereoStar 569 long ago, Reichert, who acquired AO’s microscope line, still sells parts and accesories, including the #575 0.5X secondary objective, shown below.

The secondary objective screws into the existing threads on the bottom of the microscope. Here it is installed on my scope:

Now with the secondary objective installed, I have a zoom range of 3.5-15X and a working distance of 6-8″. If I need higher magnification, I can always remove the lens. Perfect!

The second upgrade I made was to add a fluorescent ring light to the scope. I picked up the cheapest one I could find on eBay. This model is sold by Amscope, outputs 8W, and is available for under $30:

The ring light conveniently attaches to the newly installed secondary objective by tightening three thumbscrews, and provides a decent amount of light that fully illuminates both the object I’m working on as well as the surrounding workbench area, which has been surprisingly helpful. Best of all, the new light stays out of the way and provides more even illumination than the halogen projector that came with the scope.

Here’s a photo of the microscope setup as it looks today:

Conclusion:

While the changes I made are significant improvements over my original setup, I have made a few observations that may lead to even more tweaks and upgrades in the future:

The increase in working distance due to the 0.5x secondary objective is great, but it puts the scope significantly higher above the bench. I didn’t appreciate that this could be an issue until I had to buy a taller lab chair to see through the eyepieces! I’m not sure how to work around this, but it’s good to be aware that more working distance isn’t always a good thing.
The color temperature of the fluorescent ring light is very poor (cool) compared to the halogen illuminator it replaced. This gives everything a slightly depressing blue cast and is far from a true color representation. Most noticeable are tantalum caps, which go from bright orange in color to a sort of slightly orange-ish dark grey under the scope. Yuck!
Ring lights can create pretty nasty glare. This might be a side effect of how I have the ring light mounted or the distance to the bench.
The 8W fluorescent lamp is ok, but more light would be better. Fluorescent ring lights are nice and cheap, but better performance can be achieved with a significantly more expensive fiber optic illuminator. I may look into getting one of these in the future.

Despite these minor issues, I am pretty happy overall with the new setup even after a couple hundred hours of heavy use.