The Analyzer’s New Clothes

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This Tektronix 1705A L-band spectrum analyzer has temporarily borrowed a garment from an old waveform monitor.

Why?

Because as I had it on my bench powered up naked after running through a calibration on the CRT power supply, an operator comes walking in and rests his arm riiiiight here. Luckily I got him to move before any BANG occurred.

How do you even guard against awful human error like this?!

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Small naked wire and HV diode are on the input side of a voltage multiplier that puts out FU Kilovolts.

Now if you’ll excuse me— I need to make a sign for him. 😉

Bonus: The resistor the other tech never bothered to replace. Amazingly it still works, but I wasn’t gonna leave it like this!

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while we're on the subject of near crispy critters

Just Big and Lousy

Today’s— uh, victim— JBL LSR2325P active studio monitor. It’s a nice sounding biamplified monitor with an active crossover system and suspicious “Imagine” brand capacitors. Hmmmmm. 😉

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Our music producer came to me with this loudspeaker he uses to play his creations for our news director, among other things, because it was crackling and popping ferociously when the input gain knob was touched. I found the input gain knob loose on the rear panel and guessed I’d also find cracked solder joints. But where?

Input gain control is below the inverted plastic bathtub under that board. So how do you remove this plastic bathtub? Desolder the shitty thermoplastic power switch—- which will melt and eject its metal parts. WTF??!!

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You can see the switch on the panel here – it’s a snap in flange mount – the only way to get around doing this would be to cut away the plastic flange and back it out, I guess. The tub it’s in is sealed so this wouldn’t create an air leak. But still— AARGH!!! Also, WHY THERMOPLASTIC? I have a problem with this. See, if the switch starts warming up, the plastic will soften, removing pressure from the contacts, creating more heat. Eventually the fault will only clear when the switch either totally loses contact or the thermoplastic erupts into flames.

Proper electronic assemblies use thermoSETTING resins. Glass reinforced polyesters/epoxies are nice. These are resins that set either when two parts (a resin and a hardener) are mixed, or enough heat+pressure are applied to kick over a curing reaction. This reaction is a one way process and the resulting product WILL NOT MELT and soften. It may eventually be flammable, but most thermosetting resins, especially glass fibre filled ones, have a very good track record of self extinguishing.

Phenolics are very common in solderable connectors. You can always tell when you’re dealing with a phenolic resin because it will not soften and allow the connector to deform with extended heating during soldering. These resins are often colored teal blue/green, or a tan color on Amphenol products. Ever wondered what the name “Amphenol” is about? 😉

Wikipedia article on thermosetting polymers

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I don’t even want to think too hard about what that AC power inlet fixture is made of, all things considered.

The header pins leading to both the boards inside this tub were also graced with total shit-grade soldering and I reworked them. There’s one board below with the three jacks and one board above with the amplitude pad and the HF/LF trim filters. I resoldered the input pot and tightened the nut around it with some Loctite purple on it. In theory, I probably should have used blue, but I can’t find the blue, and red is right out of the question. Whatever works, right? I’ve had just as good luck with things like this using nail polish on them.

 

That’s the fate that befalls any nail polish I buy that looked GREAT in the store but when I put it upon my claws it turned out all watery looking or otherwise unsatisfying. (“NYC Color”, this means you. Well– some of their shades. Some of their newer ones are actually formulated with, well, color, in them.)

After this– I can’t wait for my assistant here to show up so I can run my fingers through his thermal insulation and hear him make silly happy squeaky meows.

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How to tell you’ve entered clickbait hell

Boy, the clickbait “news” sites are thick as a brick nowadays. So you see a link, or maybe even clicked it – how can you tell if it’s clickbait garbage or not?

First off, take a look for the story they’re talking about by searching via Google News. Look to see if the same subject comes up in a well established source such as the New York Times, Reuters, Washington Post, etc. Huffington Post kinda doesn’t count that much anymore, sadly.

But second, well, visit the link with uBlock Origin installed and active on your browser and see what happens. Do you get bombarded with prompts asking you to disable ad blocking and/or turn on desktop notifications for that site? Yeeeah—- chances are good you’ve found bullshit clickbait. Well, unless you’ve gone to Forbes, but that’s malware spewing bullshit of a different stench. Actually, I primarily run uBlock to protect against malvertising– I don’t really mind ads so much as long as they don’t block the page content or require interaction to get them out of the way first, but the ad networks have allowed sponsors to abuse the privilege of injecting active content for years. Oh how great were the days when ads could only be a 468×60 pixel jpeg or gif??

Look at the article. Sometimes you can actually, once in a blue moon, find a good reliable source cited in clickbait, then sometimes laugh as it contradicts the clickbait article you found it from. More often than not it’ll just lead you to some cesspool like Alternet though.

And then other times you’ll find something that looks so bloody insane that you think it HAS to be clickbait and then you find it proven true by Reuters, BBC, NPR, PBS, NBC, Fox, CBS, CNN, and official White House press releases, and you lose a good chunk of your faith in humanity…. oh wait, that’s just the last week or so… and the next four years… nevermind

Filters Of Wal-Mart: Worst. Oil. Filters. EVER.

A little background: I drive a car that was made when Ford and Mazda shared a lot of engineering and manufacturing resources. They both used the same engine, but with different intake systems and controls and stuff. I have the Mazda and the dipstick says FoMoCo on it! In addition, well— nobody but me knows what oil filter it takes. It actually takes a CARTRIDGE type filter. Most of the auto parts stores try to convince me it takes a spin on– it’s not. Anyway, this same cartridge filter is used on the Ford models, and I always got either the Motorcraft OEM filter or the Purolator cartridge for each replacement.

Until last night—-

I went to a Walmart store for some late night grocery shopping fun (with extra bonus pallet jack traffic and floor refinishing fumes) and picked up the Motorcraft filter. I noticed that all the boxes on the shelf looked like they’d been previously handled, and some visibly opened. I picked up the nicest looking one… Then I noticed… the box was rattling as I carried it back to my cart.

Pandora’s box.

This simply has never happened before. I opened the box to see why– what was rattling?!

What?!

The shaking was the plastic cage inside the filter rattling end to end. Curious— I’d never seen one of these where the cage was free to slide back and forth. That seemed like a ludicrously terrible idea, as if it did that with the filter in service in the engine, it’d eventually start wearing through the paper.

Then I noticed it was totally askew.

The whole thing tilted a bit like the Leaning Tower of Pisa. Hey, what’s up with that seam? Normally those are pretty closely bonded.

OR NOT! Not bonded at all! I could totally open the seam up with no real effort.

 

Now I’d like to point out the color of this filter media. Normally, oil filters are made of a thick paper with resin coated fibers, or sometimes a synthetic nonwoven fabric. In the case of resin coated cellulose fiber paper, a thermosetting resin may be used. This is a material that remains workable and flexible during the assembly of the filter, then kicked into its final set state by the use of heat.

This filter shows signs of very uneven heating, coating, or both. No loose fibers were visible… which was a cut above the fresh hell you are about to see here.

Briefly— if you were to place THIS filter in your engine and run it there is a good chance most of the oil circulation would bypass it. Chances are you’d get away without any engine damage.

What follows are weapons of engine destruction.

Fram.

Fram is a name known widely for low cost, retail channel filter products— the cheap ones you’ll find at your local auto parts store. They were originally built by a division of Allied Signal, who have been bought out by Honeywell.

A wonderful testament to the quality of Fram filters follows. This is from the excellent Oil Filters Revealed page that showed me, years ago, that not all oil filters are created equal.

Russell,
I obtained great satisfaction from reading your oil filter survey.

I worked for two years as the oil-filter production line engineer in
an Allied-Signal FRAM facility and I can confirm every bad thing you
have said about FRAM automotive filters. That’s from the horse’s
mouth, as it were.

I’m also a quality engineer and can confirm that FRAM applies no
quality control whatsoever to any of the characteristics for which we
buy oil filters. I frequently saw filter designs which were barely
capable of meeting J806. Many of FRAM’s designs will block and go to
bypass after trying to filter very little contamination. There were
often leakage paths at the paper end discs when these were not
properly centered on the elements. Some designs had the pleats so
tightly packed against the center tube that they would block off in no
time. I had discovered that the FRAM HP1 that I had been buying for
about $20 Cdn was EXACTLY the same as a PH8 inside – the only
difference being a heavier can – no advantages in flow capacity. The
paper filtration media was of apparently poor quality and the process
of curing the paper resin was very inconsistent – elements would range
from visibly burnt to white. FRAM’s marketers admitted that there was
just about no way the public could ever prove that an oil filter
contributed, or did not prevent, engine damage. The only thing FRAM
tested for was can burst strength. Another problem that they have from
time to time is in threading the filter base – often there are strands
of metal left behind on a poorly formed thread.

I have not used a FRAM filter since I started working there. Their
claims are entirely and completely marketing bullshit.

If people really want to protect their engines, a good air filter is
vital (which excludes FRAM from that list as well) and a combination
of one depth and one full-flow hydraulic filter, together in parallel,
will do the job of filtration to perfection.

Thanks for doing a great job in trying to get the truth out! You can
quote me anytime.

[name omitted to protect submitter]

Nice to see that Fram’s complete and total lack of quality control continues to this day. The nice thing about having a car that takes a cartridge filter — NO SECRETS. In fact, I always inspect the cartridge after removing it and letting it drip dry a few minutes to check for any metal or plastic bits. Try that with a spin-on filter!

 

First up– the Fram Tough Guard.

Well, nice to know the resin curing issues were not present as there simply appeared to be no resin. None at all. On handling the filter, paper fiber came off on my hands. The uneven pleating is a little weird but not a show stopper (I’ve even seen it on Purolator filters for the first pleat or so right near the seam) and the seam is at least sealed, albeit… questionably so, with a great besplodging of glue.

But we need to have a look inside.

Hey wait WHAT?
First of all, that sealing ring around the edge appears to literally be a heat sealed on piece of kitchen scrubber. It’s got enormous pores and would allow contaminated oil to bypass right through it. Second, do you see the support structure?

No.

There is no support.

Oil flows through the filter from the outside in. Under high RPM operation, it may be presented to the filter media at a pressure of over 100 PSI. In response to this, I suspect this filter would simply cave in. Combine that with the loose fiber issue and this filter may spell death to your engine. A structural failure of the filter would shower paper fibers through the entire engine, where they can clog the fine oil passages to bearings, build up in the variable valve timing system, jam up solenoid valves, and possibly even block the oil pump’s pickup screen. That’s a whole lot of GAME OVER right there.

 

Well, at least this one only left slight amounts of fiber on my hands, compared to the next model up—

This is supposed to be Fram’s finest. The crem de la…. CRAAAAAAPPPPPPP

A mesh backs this filter media. It looks a little like the mesh that supports the cotton gauze media on my K&N air filter. The K&N, however, never has to deal with this kind of pressure!!

Royal Purple’s oil filter has a similar mesh as part of its media, however, its media is actually

a) bonded together;

b) backed up by a metal tube to hold the oil pressure!

 

Now let’s look at that media— as it RAINS loose fibers all over my hands.

This is Fram’s fancy schmancy “synthetic” media. I guess it’s supposed to be bound together by a resin, but that resin appears to be… just… not cured. Not at all. This filter sheds like our assistant overnight guard at work.

Dear human, please take your other hand off that shiny rectangle and place it upon me as well. And go buy yourself a Purrrrrrrrrrrrrolator.

 

A metal channel is crimped over the seam, and kind of…. rudely crushed at one end. Possible weak spot, as if the media ITSELF isn’t.

The filter media.

what fresh hairy hell is this

 

If the other two filters were merely bad, this one… this one is malevolently awful. This one was shedding little dust bunnies of fiber as I handled it. Touching the surface would raise a layer of fibers. Whatever the method used to form and cure the nonwoven fabric media was, it was not done right– resin not cured, insufficient heat/pressure, who knows. It’s a major ugly quality control issue– oh wait, what quality control?

(Note that the manufacturing has been offshored to China since that statement about the quality control was written.)

So, in the case of the two Fram filters, this “quality” is believable. The Motorcraft one is an odd duck though and I honestly suspect a supplier FAKED IT. Here’s why– all of the boxes on the shelf had wear as if they’d been handled, opened, and repacked at some point in time. I have to wonder– were they boxes from factory rejects or overstock that got restuffed with fakes? Dare I say— could their own service centers be involved, saving the retail boxes from filters they install in customers’ cars and repacking them with bulk packed shit filters? This wouldn’t be the first time I’ve seen a lot of defective crap hit shelves at Walmart – I once got burned on an entire purchase of *SIX* SD cards there that turned out to be genuine yet defective repackaged Sandisk products.

They also had some filters from K&N and Bosch there. The Bosch filters, as I recall, are Champion Labs “Performance” line filters and they looked just fine.

From K&N’s website.

The K&N’s– they were the “Pro Series” being sold at the HP series’ prices. See this image for why the HP series rules. Not only does it have better filter media inside, but you don’t need an oil filter wrench to install and remove it. The “Pro Series” are just the ‘Performance’ model Champion Labs filter with the K&N name stamped on it and a higher price tag. This same filter element is used in ACDelco OEM filters.

 

In short, do not buy a Fram filter or any oil filter from Walmart unless you really want an excuse to do a full engine teardown and overhaul. And if you want a K&N, spend the few extra bucks on the HP series. You’ll be glad you did. For all practical purposes though, it’s the same as the Mobil 1 filter with an easy installation/removal tool built in.

Misspent youth – the Yihua YH-305D

Boy, was I ever young and stupid. It was the summer of 2004 or so, and various Chinese electronics vendors were just starting to flood the US market with some really cool looking toys, and the quality hadn’t faded to zero on them yet either! Mostly….?

At the time I’d just gone through a big mess with most of my workshop having been left out in the rain for several days in my absence, so I didn’t have a power supply. I bought this Yihua YH-305D on eBay and thought it was pretty great for the price, even after it arrived with the instruction manual calling it a “DC POWRE SUPPY” and the plastic nuts on the front panel binding posts don’t actually… work. (I got around this using banana plug leads.)

Years later it finally occurred to me to be suspicious of the fact that the constant current regulation is sloppy as hell, and the cooling fan starts to run if you draw more than one amp off it continuously. At five amps steady draw, the Powre Suppy doesn’t get noticeably warm, but the fan continues to howl forever.

I opened it and realized just how misspent my youth truly was.

wp-1483573643309.jpgThis… beautiful… board greeted me right away. There are places where traces kinda got half etched over there on the side then subsequently, but incompletely, covered with solder to fix it. Ummmmmmmm yeeeeeaaaaah D-

wp-1483573603318.jpgThe underside of the regulator pass transistor assembly. That’s three *supposed* 2N3055 transistors, paralleled. Why would you need three 2N3055’s for five amps?? You can run 15 amps through ONE real 2N3055 if it’s heatsinked properly. Oh wait, I forgot the key word… real. Genuine. Official. Not Pure Unadulterated Chineseium. I couldn’t get a picture of the labels on these “2N3055” transistors that were SO GOOD that they had to put three in parallel to pass 5 amps, but I was able to get a peek at it and they were printed in a gray looking ink with a nonsense logo– it looked like the Marvell Semiconductors logo??!! Either way, this video details what I’m probably actually looking at and why they are… very… very… derated.

The heatsink they are bolted to also explains the fan behavior. It’s nothing more than a flat plate with very little mass and surface area.

wp-1483574274591.jpgThe fan sucks up air from right above it and exhausts it out the back when the thermal switch seen in the background snaps on. I’m not sure how hot it has to get to trigger that, but it sure gets there in no time.

wp-1483573638001.jpgThe main filter capacitor looks underwhelming and I have my doubts it’s actually a Rubycon as its clothing would suggest.

 

This is paired to, uhhh, the death capacitor, as I lovingly call it. If you are using a power supply like this as a limited current source and you lose connection to the load momentarily, and the voltage limit is significantly higher than the voltage the load pulls it down to, any capacitor on the output will be charged up to that level. Once connection is reestablished to the load, it is presented with very high available current at this higher voltage. I detonated some high efficiency white LEDs under test with a power supply like this years ago while trying to develop a boost converter based driver for solar lighting applications and was royally pissed. So, without further ado, the death cap…

wp-1483573631845.jpgand…. the… rubber cement disaster of the century. The entire front of the supply is just…… bespooged with this cement…. Another red cement is found splattered all over the place as well. At left in the above picture is the digital meter board which I am not even going to touch let alone try to calibrate the screwed up zero point on, FORGET THIS

 

wp-1483573620558.jpgThe board is supported only by one small bracket from the rear; if I drop this power supply it will experience the sweet release of death it so sorely longs for.

 

Yeah. I was young and stupid and I bought this.

 

There’s a great thread on EEVBlog’s forum about these, including the wonderful thing that happens when you switch one on and it goes wham, overshoot, boing, boing, boing, and either stops bouncing or… not…

 

American Dream… I’m so done

I’m so very very DONE and so are your chances of ever getting anywhere on the roads in northwest Miami-Dade in 2020. I had heard nothing but radio silence on this project for over a year, and this is probably why– they were trying hard to apply decorative wallpaper to an elephant in the room to conceal it.

“It is unlikely that all needed interchange improvements will be approved and constructed by 2020, the build out year for ADM,” Lisa Colmenares, a state transportation planner for South Florida, wrote in a Nov. 23 letter to Miami-Dade. “If any of the interchange improvements fail to be approved … by 2020, the base transportation network that is the foundation of [the county’s] traffic analysis will be invalid.”

They don’t even know—–

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Here’s its likeness in cable nightmare form.

Bang!

I’m still baffled by this one. I’m going down 595 eastbound past Davie when there’s suddenly a massive bang… I didn’t see any objects in the road prior to this but something must have hit hard. I pulled over and found the wheel well liner wrapped around the wheel and what’s left of the front bumper unsnapped from its tracks.

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There was once a big black plastic pan here.

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Flapping in the breeze.

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I do hope that dangling wire would have been for the fog lights on a fancier trim model

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The remains of the pan I had to remove because it was dragging and there’s nothing left to attach it to

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There is no real evidence of what may I may have hit in the road, but it sure did a nice job of demolishing all the plastic parts.

Oh well. Likely coming soon: a post in which I detail reassembling the front of a car in 88 degree December weather.

Crap Power Strips

This has significantly bothered me for a while.

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This is one of the most common power strips available now, as it’s the least expensive available out of China. Note what happens if you miss just a little plugging in a two prong plug. If you touched the prong here and any grounded object, hi diddly shockarino, neighbor!

But guess who doesn’t seem to have a problem with this.

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Genuine meaningless hologram.

This strip is available under a number of brand names including General Electric, Westinghouse, Belkin, Sunbeam, whoever the retailer licensed a brand name from that week. You should not buy it.