Considering purchasing a Logic Analyzer

[keeney123]

Re: Considering purchasing a Logic Analyzer

I think you will be alright with the higher voltage. I guess if you can not get any schematics on this thing Then you might as well start replacing things. First I would run all the diagnostics on the logic analyzer with the O-scope board out, then start replacing things on the O- scope and see if you get the trigger back. Some of the circuity will most likely be to fast for you to look at with your other scope. You are kind of flying blind. You have to figure that it worked at one time. There is a 95 % chance it is a component that is bad. The only problem with troubleshooting this way is if you have parts dependent on each other, so that if you replace one part the other part will take the new one out and visa-versa.

[stj]

Re: Considering purchasing a Logic Analyzer

the battery-backed ram may still be good, you need to back it up because it's probably got calibration data in it.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

the battery-backed ram may still be good, you need to back it up because it's probably got calibration data in it.

Okay. If I replaced it, once I got everything working good, I was going to try and recalibrate everything. You're right, supposedly it holds the calibration data. I just figured as old as it was, it was probably bad.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

I think you will be alright with the higher voltage. I guess if you can not get any schematics on this thing Then you might as well start replacing things. First I would run all the diagnostics on the logic analyzer with the O-scope board out, then start replacing things on the O- scope and see if you get the trigger back. Some of the circuity will most likely be to fast for you to look at with your other scope. You are kind of flying blind. You have to figure that it worked at one time. There is a 95 % chance it is a component that is bad. The only problem with troubleshooting this way is if you have parts dependent on each other, so that if you replace one part the other part will take the new one out and visa-versa.

I still haven't tried HP yet, still can't find an e-mail address. How do you guys know so much about all this stuff? It just blows my mind! So, run the diags on the logic analyzer first, with no o-scope module, then plug the o-scope module in, run the diags on the o-scope module, record the results, replace the caps (when they come in the mail), run the diags again. If it still fails, replace the IC, run the diag again, right?

[stj]

Re: Considering purchasing a Logic Analyzer

i'v seen those zero-power rams go 20years+
the data in it may be something you cant regenerate that was created with a test-rig.
it may also contain a MAC or serial number for the board.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

I don't think this one contains that kind of data Stj. I read on EEVBlog how I guy had to replace his because it wasn't retaining the calibration data. He gave a link to Mouser I think, where they had replacements and said just unsolder the old, solder the new one in, recalibrate and away you go.

20+ years?! That's insane. This oscilloscope module is around 20 years old. If it's working, I'll probably just keep it I guess. No sense in replacing something that isn't broke. Got ten 10nF 100V 10% MLCC SMD caps coming from Mouser. I was surprised how cheap shipping was compared to Digikey. It was nice.

[stj]

Re: Considering purchasing a Logic Analyzer

you can cut the top off those rams, extract the old battery, and glue a coincell holder to the top of them.
i'v done loads.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

No shit? If it is bad, maybe when I replace it, I'll open it up just for the fun of it. When I see words like Lithium, I always get a bit nervous. I have a friend that wanted to start making vaporizers and using custom batteries but doesn't want to do the work to learn about anything. He says the lithium ion batteries are only dangerous when they have this protection circuit built in. If you get the batteries without the protection circuit, you can just use them like normal batteries in circuits without any problems. It didn't really make sense to me why protection circuits would make something more dangerous. I do have to admit though, I know absolutely nothing about them. For all I know, there might not even be something called protection circuits for lithium ion battery packs.

[keeney123]

Re: Considering purchasing a Logic Analyzer

Sounds like non-volatile RAM with battery back up.

[stj]

Re: Considering purchasing a Logic Analyzer

exactly,
it's a chip with a small lithium coincell and sometimes a crystal ontop potted in a plastic box.

as for spork's idiot friend, it's cells without the protection circuit that are dangerous.
the circuit limits the current and stops the battery being flattened so low that it's dangerous to recharge.

[keeney123]

Re: Considering purchasing a Logic Analyzer

exactly,
it's a chip with a small lithium coincell and sometimes a crystal ontop potted in a plastic box.

as for spork's idiot friend, it's cells without the protection circuit that are dangerous.
the circuit limits the current and stops the battery being flattened so low that it's dangerous to recharge.

Is that the same sort of set up like the Texas Smart Watch in the 1980's with a 64 bit serial fed security code to program the chip?

[stj]

Re: Considering purchasing a Logic Analyzer

no, it's just a cmos ram - sometimes with a clock in it.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

exactly,
it's a chip with a small lithium coincell and sometimes a crystal ontop potted in a plastic box.

as for spork's idiot friend, it's cells without the protection circuit that are dangerous.
the circuit limits the current and stops the battery being flattened so low that it's dangerous to recharge.

He wanted me to solder the circuitry for these vaporizers but I refused. He was a bit upset but I told him, if something went wrong, those things could end up blowing up in someones face! I said I don't know anything about lithium ion and don't feel comfortable at all using them.

He found plans on the internet for something that he called a "mechanical mod". A vaporizer that doesn't use any solid state electronics. It has a battery, some really, really, really thick braided wires and a mechanical switch. Whenever he clicked it, there was this giant bolt of electricity crossing through the air to something. It was enough where it started melting the plastic. I told him I thought a safety cap (or maybe it was a diode) would fix it but he said it was fine and if it wasn't, they wouldn't of posted the plans on how to make it on the net. I'm not an expert in physics or anything, but I think what was happening was there was a magnetic field that was being generated and the field was collapsing, generating something called a spark gap (or something like that). The spark you saw going from the unit (maybe 1/2 an inch to a inch long!!!) was much larger than what you see from a spark plug. He was convinced the problem was the braided wire and just switching it to solid wire would fix it. I don't know if he ever tried replacing the wire or not. It seems he just wants to make money but is sooooo lazy, he just refuses to actually put any effort into learning how this stuff works. I've pointed him to free resources online to learn about electricity and building circuits but he just never reads them. I've also given him one of those Make It: Electronic Component Kits but again, just doesn't want to put any effort into learning I guess. Kind of sad.

He's trying to sell these vaporizers he's making and I'm afraid he's going to end up hurting someone, real bad like.

[stj]

Re: Considering purchasing a Logic Analyzer

he WILL get a battery explosion or a meltdown with that - i would hurt him if he sold one to me!

he is simply shorting the battery with a bit of wire thin enough to act as a heating element.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

he WILL get a battery explosion or a meltdown with that - i would hurt him if he sold one to me!

he is simply shorting the battery with a bit of wire thin enough to act as a heating element.

Agreed. That's why I refused to help. With the "mechanical mod", he wasn't using lithium ion. But it's just stupid. Things like spark gaps, generally, they're a problem. There's a few cases I guess where you would purposefully want one. It's just playing with fire man. He tore about a few from China and felt because they were so crappily built, no matter what he did or how he did it, it'd be safer than theirs.

If I were going to build something that had the potential of hurting someone, you'd be damn certain that I would research the heck out of it and then submitted the schematics and design online for peer review, on a place like this. I even tried getting him to go here, to this forum, to ask questions about stuff. It just seems he doesn't care though.

[stj]

Re: Considering purchasing a Logic Analyzer

you can by oil vaporizers from model shops.
http://www.rapidonline.com/steam-smoke-generators

[keeney123]

Re: Considering purchasing a Logic Analyzer

If you are smelling melted plastic something is wrong.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

If you are smelling melted plastic something is wrong.

I like that! I've smelt melted plastic before! When I was a very young child, I was addicted to video games. I've since kicked the habit. But I would play whenever I could back then. Finally, after what seemed like a lifetime of begging my parents, they caved in and bought the family an original 8-bit NES system. We had never even played a video game before, so this was all new to us. I instantly fell in love with it. I remember how my mum used to take me to Toys -R- Us and they had tons of NES games for sale. They also had Gameboy games.

The store had this setup where you could try a few Gameboy games threw the NES system. I didn't realize they were using an adapter. Eventually, I got my own Gameboy and as time went on, I decided I wanted to hook it up to the TV like they had in Toys -R- Us. I took the NES apart and I took apart the Gameboy. I grabbed a wire from my dad's basement and just started randomly connecting stuff from the Gameboy's circuitry to the NES circuit board, thinking there was some magical stuff in both systems and if I could just figure out where to the connect the wire, I'd successfully have the Gameboy hooked up to the NES. The only magic I found was that damn magical smoke! And boy, did it ever come out! The wire I had got really red and hot. It burned my little fingers and the NES and Gameboy didn't work after that.

To this day though, the original 8-bit NES is my absolute favourite system. I still play it once in awhile. I also like the Sega Master Systems but I don't have one anymore. It's very sad. That's a real nice system, the Master System.

[tom66]

Re: Considering purchasing a Logic Analyzer

I had an HP 54501A with the battery backed RAM module, mine was still going after 22 years old and according to the guy I sold it to is still working making it almost 26 years on one battery. (mfg in 1990)

Pretty impressive for a lithium cell battery.

I have to say it's hard to beat the Rigol DS1054Z now as it's a 4 channel scope, 1GS/s sampling with 50MHz bandwidth and serial decode function (I2C, UART, SPI etc.) You can hack it and upgrade all the functionality very easily.

[Spork Schivago]

Re: Considering purchasing a Logic Analyzer

They just don't make batteries like they used to! I didn't even know lithium ion batteries were around back then. Or are these lithium batteries not lithium ion? I know in laptops, we're lucky if we get a year out of them! Of course, they drain a lot faster with all that power, you know?