product somebody could do

There is a *lot* more to (electrical) engineering than RF design. And, yes, the RF types I know have VNAs by the boatload. ;-)

Personally, I have a couple of Fluke 77s. That's it.

I've never messed with that LCD. I'll have to play with it. The sluggishness likely is the software.

The contrast on that one is adjustable. It's in the basestation menus. It's got a nice backlight (also adjustable in that menu set), too.

The above displays are graphics-mode over I2C. A badly behaved I2C, at that.

Sometimes things just work out. Usually not when the customer is looking, though.

Hi Keith,

Not even any old oscilloscopes kicking around? I was given an old single-channel 10MHz Heath-Kit when I was ~15, and one of the first purchases I made after getting a regular job at 16 was a 30MHz dual-channel unit. :-) (Branded by JDR Microdevices -- it was just a generic Taiwanese import, though. $499 was an awful lot at $3.35/hour!)

The closest thing we're currently using (and it's a pager, not a wireless intercom) has a very programmer-friendly byte-wide interface where each byte you send it ends up as a column of pixels (and it will automatically move the internal memory pointer to the next column for you and has commands to position that pointer, clear the entire thing, etc.) -- makes it really easy to display text (and we're just banging it directly with an AVR). There's some weird little problem wherein sometimes it remains blank after reset, although we've never seen it happen in production usage -- only on some test fixtures we have that let us really abuse the poor thing during development. As such, we've never tracked down the cause of the problem, although I would wager there's about a 90% chance it's our own software not getting the initialization timing right, not waiting for voltages to stabilize, etc.

The only other problem we've had with them is that they connect via a flex PCB and the epoxy that holds this flex PCB to the LCD's glass is rather fragile (brittle) -- if you don't treat the things gently, it's not hard at all to rip the flex PCB entirely off the glass.

Ironically in that scenario I had seen ads for these Hitachi-compatible Noritake VFDs and mentioned we might like to use them (this was a piece of capital equipment for the semiconductor industry -- price tag, $750k -- fell to $600k if you purchased quantities...), but since they were something like $45 vs. $20 for the LCD, the engineering manager said, nah, stick with the LCDs. Then, after we'd built the first few, some manufacutrer's rep comes to visit us with his display case of -- among other things -- Noritake VFDs, and once said manager sees how nice they look in action, makes the decision on the spot to switch over to them.

At one point this machine went through some cost reductions -- they went from polished stainless steel sides to painted carbon steel: Something like $8k down to $2k!

---Joel

Nope. I've never owned an oscilloscope. I've thought about it but really don't want to do that stuff at home. My first calculator was $400 and I was making $2.25/hr, part time, married, and (wife and I) paying my way through school.

This is the same sort of thing, except a crappy I2C interface bolted on the front end.

They don't let me play with the firmware and all that was done long before I was hired. Everything has been abstracted to menus now.

That's typical.

They do look nice but moving marketing targets are always a problem. Our marketing/new products manager loves moving the goal posts. The engineering manager (my boss) is doing his best to nail his feet to the floor before we start, otherwise his changes are still our fault.

Reality strikes hard, sometimes. ;-) I'm going through a similar deal, but I don't think the cost reduction is really going to happen, even though I spent the last four months on it. Oh well, the fun part is done, anyway. ;-)

Oh, I'm disappointed! So little creativeness...

--
Thanks,
Fred.

I've seen creativeness in fields like this. But mostly followed by a serious blow from financial reality :-(

--
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Often this is caused by a botched or non-existing brown-out reset circuit (BOR). For reasons that completely elude me it has taken uC chip designers decades to figure this out and some still don't have it. So I typically never trust them and roll my own BOR outside the uC. Meantime you can get fairly good chips for that purpose, for example the from ON Semi.

I've done that several times, convinced clients to ditch the expensive polished aluminum for steel. Dropped the cost way down, weight was hardly changed because you can make steel thinner, much improved EMC, lots of stuff was now welded and the whole thing exhibited almost the robustness of a tank. A wee mod down the road? Big deal, drill, tap, screw it down. No PEM nuts.

--
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Those great old boat anchors are going for a song just now, so if your back is up to the strain, go for it. I bought an old HP rack from Ecnerwal last year, which is now nearly full.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058

email: hobbs at electrooptical dot net
http://electrooptical.net

I was the typical geeky kid who wanted to "do" electronics long before anyone was about to pay me to do so, so largely out of necessity I started acquiring some equipment of my own. I thought I had almost died and gone to heaven when I got a job in college buliding/designing/troubleshooting power supplies, amplifiers, etc. wherein I had access to a blanket order account with Newark, fairly decent test equipment at the physics department's electronic shop (oddly, the electrical engineering department didn't *have* an "electronics shop"), *and* access to a machine shop.

The machine shop even came with a designated student helper named -- and I'm not making this up -- Elmer. :-) Good guy, although unfortunately (for me) he retired while I was there. During the couple of years I knew him, he'd often segue into his planned fishing trips during that retirement while helping you turn something on a lathe or whatever.

The physics electronics shop (PES) was run by a Real Live World War II vet named Mike, who'd been a radar tech. He was a good transistor-level designer himself, but not really the world's greatest instructor -- I think he'd kind of gotten to the point where he'd been cranking out designs for so long he sort of knew what all the circuit topologies "should" look like and what the "likely" component values were, but he had forgotten a bit of just *why* it was all that way. (And there was a bit of a disconnect between us kids who were being trained for what was surely going to be an "all digital" world -- they cut the analog circuit design classes from 3 semesters down to 2 while I was there -- and an old analog guy like him...)

I have a lot of fond memories of working at the PES. It had a great cast of characters -- besides Mike, there was a (much younger) ex-marine who was doing digital design and had parents who farmed tobacco; if you were up for it he was able to get you a job farming it during the summer. One other full-time guy had his own farm and seemed to do more testing and assembly than design; he was known to occasionally interject rather non-sequitir comments such as, "Have you seen the prices of hogs this week?" while you were discussing the operation of a circuit. :-)

Yeah, this is a very common problem... marketing guys often don't know what they really want or what will really sell until they start a few discussions of proposed plans with key customers or whatever, at which point from the feedback they receive they suddenly want to change half the design.

I'm amazed at the pricing levels the pro-audio market is willing to support. We had a marketing guy from one of the big pro-audio companies come right out and say that whether the "typical" setup of a base station and 4 wireless headsets was $5k, $10k, or $15k, the price was seldom going to be a deal breaker for customers -- cheaper is better, of course, but he'd be able to make the vast majority of sales even at the upper end of the price spectrum; customers care far more about features and reliability than cost.

---Joel

I was into electronics as a kid, too. I didn't have an oscilloscope, though. I did have a really nice Ham receiver, though. I got a job in college as a test and repair technician for the EE department, where I had access to any test equipment I wanted. I've been in similar (or better) situations since. I have no need for my own test equipment. I don't do this stuff at home anyway.

The electronics shop in our EE department had two full-time technicians (one the manager) and four to eight part-time students. I worked there the four years of college. It didn't pay much but I learned a lot and it opened doors when I graduated (a terrible year for newly-minted engineers).

Sounds like you worked in the same place I did. ;-) ...though we worked full time during the summer. Well, if we didn't do summer school.

It's worse.

Yep. Kinda like 'scopes. ;-)

That's great.

Before I was married, I didn't really do it at home, I just stuck around late at work many nights of the week. :-)

My school had this annoying policy that if you weren't taking classes during the summer, you took about a 10% pay cut -- something about how tuition fees somehow financed us lowly student hourlies, so if you weren't paying tuition you didn't get that part of your pay.

I've been following Joerg's learnings lately in that even if I (well, the company) could readily afford to get a Tek or Agilent scope, in many cases I think it makes more sense to get an Instek or similar -- especially when the low-end of Tek and Agilent are engineering and manufactured off-shores (i.e., on-the-cheap) anyway.

We do still spend plenty on fancy VNAs and spectrum analyzers; our Agilent salesguy probably isn't too unhappy if he loses a $10k scope sale to Instek when we turn around and hand him a $60k VNA order.

---Joel

I don't remember that far back. ;-) I've always work the hours that are needed. Or in the case of the year contracting, all the hours they'd let me, which ended up averaging >60/wk. ;-)

We weren't allowed to hold the job if we weren't full-time students but summer wasn't the "normal" school year so didn't count. I generally did take classes during the summer so I could take a lighter load during the year.

The tech who does the final inspection/repair has an Instek. It sucks. We have a couple of Tek's in engineering, one of which is OK. I try not to use the other. There has been a lot of used stuff around (go figure) but money is tight (again, go figure). It would be an ideal time to stock up, but...

We don't have a VNA at all. We don't really need one. We have one Aligent spectrum analyzer but it lives in the service department's screen room, for some reason. My CPOE is a bit equipment poor. Most of my career I've worked where money for such equipment was no object, though.

The first part of that sentence could be construed as ... ahem, let's not elaborate :-)

But I did the very same. Came home at 9:00pm or midnight, slept, back at the company the next morning.

We were strictly budget-limited to 20h/wk.

Why does it suck? I have their 200MHz/4ch and it's been great. Then several clients bought that brand as well and were mighty surprised that they were not milked for more money when they wanted PC software and LabView drivers (those are free downloads at Instek). What did suck big time was "scopes" such as the TSD220 series.

It's amazing what can be done with simple tools. I've done jobs using sound cards, demodulators and a dipmeter where folks have gnashed their teeth with some big expensive analyzer. Wish I had a dipmeter that goes to a GHz or higher.

--
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late

Yes, one is surprised he's still married. ;-)

I've done that, in stretches, in every job I've had. It comes with the territory. I'm getting too old for all-nighters, though. ;-)

I wouldn't have taken the contract. ...or do you mean in school? We were limited to 20h/wk while school was in session. Otherwise, the shop was open a normal 40h shift.

(i.e.,

Triggering sucks. The controls are poor, at best. It's cheap and displays its cheapness constantly. I wouldn't have one at home.

I've done several M$ projects where the only tools I had were a few Fluke-77s, a Tek 454, and an 8051 emulator. A cheap logic analyzer would have saved me a couple of months work once, but my boss was too cheap.

We use sounds cards all the time. Some have real issues, though. I haven't found one that will do everything well.

[...]

It was work at an institute of our university while I studied for my masters. Formally they couldn't take anyone before passing 4th semester tests but I was sort of the unspoken exception. Much of my job was salvaging capsizing final projects of others, mostly when they ran into hardcore unforeseen problems. Chips obsoleted, internal EMI pollution and such.

[...]

The controls on mine feel a lot more robust than on many Teks IMHO. Triggers nicely. In fact, it doesn't feel cheap at all. Take a look at the GDS-2204 if you get a chance.

You can buy We use sounds cards all the time. Some have real issues, though. I

I use a no-frills laptop with almost mil-spec robustness, a Durabook D14RA. Only 18 bits sound bit very clean. I guess it helps that it doesn't have a plastic enclosure like most laptops. But it's heavy.

--
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Something like: ? datasheet: Handles 1-4 lines, up to 20characters, pwm backlight, serial controlled

16.95$ pcb and all, source code code included so you can add the missing features/change it to your needs. Can i have the 83.05$ you save? ;-)

Best Regards

Steve Sousa

About a fifth of the work is done, so the price is about right.

John

On a sunny day (Mon, 18 Jan 2010 03:47:59 -0000) it happened "Steve Sousa" wrote in :

I told him so before, I have a LCD like that controlled by a PCF8574, creating an i2c interface for it: ftp://panteltje.com/pub/i2c_LCD_detail_img_1764.jpg That is 20 years old... BASIC program to drive it available.. No PWW for the backlight on that one, backlight on DC. To test those 2 line LCDs you need no controlled backlight.

Don't know that model and neither does Tek, apparently. ;-) The scope I usually use is a TDS3034. I'm not a big fan, but it works.

Instek

I remember using Poloroid cameras for screen shots.

They're all defective in some way. Mostly their grounding is the pits. Laptops are a real problem (unpolarized power cord).

That's because it is from Instek :-)

Not this one. It never gave me ground noise problems.

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