USB function generators?
in [Design]
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From: Joerg on 11 May 2010 11:19 JosephKK wrote: > On Sun, 09 May 2010 09:23:13 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> John Larkin wrote: >>> On Fri, 07 May 2010 14:13:49 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> Gents, >>>> >>>> Unless it rains on Sunday >>> It's raining here, headed slowly your way. >>> >> Yup, that's why we just walked the dogs :-) >> >> >>> Got leaks? >>> >> We had one that I diagnosed as too short chimney flashing, when rain >> storms in sideways. Just like Forrest Gump said, there's sideways rain, >> upside down rain, big old fat rain ... >> >> >>> Rain in May is unusual here. We had a very wet winter, lots of >>> snowpack, long hot (indoor) showers in the forecast. I hope it's a >>> trend. >>> >> My wife just lit a load in the wood stove. In May! Global warming ... >> ROFL ... >> >> Anyhow, two cords of wood 10 years ago, then three, now four, and next >> year we'll order five because we almost ran out this time. > > If this return to more normal winter weather presents itself next time > you might better consider 6 or 7 cords. Or a lot more insulation. Normal? We are still in contact with the kids (now retired) of the first owners. The house was built in 1970 and they can't remember anything like that. In fact, the house had a fairly weak radiant heat system which a later owner simply cut off with an angle grinder (%#&*!!). Met a neighbor yesterday, they already upped the ante to five cords for next season. Guess we also should have ... or move to another state. In view of the pension funds blowing up around here that may be necessary anyhow. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 11 May 2010 11:23 JosephKK wrote: > On Mon, 10 May 2010 09:05:25 -0700, Joerg <invalid(a)invalid.invalid> > wrote: > >> JosephKK wrote: >>> On Fri, 07 May 2010 14:13:49 -0700, Joerg <invalid(a)invalid.invalid> >>> wrote: >>> >>>> Gents, >>>> >>>> Unless it rains on Sunday and I have some time I might just junk this >>>> dreaded Wavetek Model 23 generator. Looked around for USB-based >>>> generators and found a nice li'l scope/gen combo: >>>> >>>> http://www.allspectrum.com/store/product_info.php?products_id=2778 >>>> >>>> Not a lot of info, seems it has no galvanic isolation from the computer >>>> like some others <knuckles turning white ...>. However, unlike many >>>> others it does go down to 5 millihertz so can be used in machine, stress >>>> and vibration testing which I need to do at times. >>>> >>>> What do thee think? >>> I think it is overpriced and underpowered. >> >> Overpriced? I've seen it on sale as low as $200. What alternatives are >> there, other than a big vintage box? > > Underpowered because of the power limitations of USB. Overpriced because > they did not solve the galvanic isolation problem or the power problem > with a wall wart or a cord brick (both of which could have been easily > done at that price point). Yep, the lack of isolation is a problem. Can be fixed but that'll cost users another $100. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: miso on 11 May 2010 15:12 On May 11, 8:14 am, Joerg <inva...(a)invalid.invalid> wrote: > m...(a)sushi.com wrote: > > On May 10, 4:18 pm, Joerg <inva...(a)invalid.invalid> wrote: > >> m...(a)sushi.com wrote: > >>> On May 9, 6:34 am, Joerg <inva...(a)invalid.invalid> wrote: > >>>> m...(a)sushi.com wrote: > >>>>> On May 8, 4:16 pm, n...(a)puntnl.niks (Nico Coesel) wrote: > >>>>>> "m...(a)sushi.com" <m...(a)sushi.com> wrote: > >>>>>>> On May 7, 2:13=A0pm, Joerg <inva...(a)invalid.invalid> wrote: > >>>>>>>> Gents, > >>>>>>>> Unless it rains on Sunday and I have some time I might just junk this > >>>>>>>> dreaded Wavetek Model 23 generator. Looked around for USB-based > >>>>>>>> generators and found a nice li'l scope/gen combo: > >>>>>>>>http://www.allspectrum.com/store/product_info.php?products_id=3D2778 > >>>>>>>> Not a lot of info, seems it has no galvanic isolation from the computer > >>>>>>>> like some others <knuckles turning white ...>. However, unlike many > >>>>>>>> others it does go down to 5 millihertz so can be used in machine, stress > >>>>>>>> and vibration testing which I need to do at times. > >>>>>>>> What do thee think? > >>>>>>>> -- > >>>>>>>> Regards, Joerg > >>>>>>>>http://www.analogconsultants.com/ > >>>>>>>> "gmail" domain blocked because of excessive spam. > >>>>>>>> Use another domain or send PM. > >>>>>>> USB is always a driver hassle. I try to buy USB devices that also work > >>>>>>> in Linux, so if the company goes bust, you can at least run the box > >>>>>>> under linux. > >>>>>>> $300 would get you a nice function generator at a ham swap meet. My > >>>>>>> PM5191 was $125 in a freakin' store (RA Surplus, now defunct) years > >>>>>>> ago. You can't get much money for low bandwidth generators these days. > >>>>>> Well... a good HP3314A still sells for a couple of hundred. More > >>>>>> recent Agilent generators fetch even more. AFAIK those are USB and/or > >>>>>> ethernet controllable. > >>>>>> -- > >>>>>> Failure does not prove something is impossible, failure simply > >>>>>> indicates you are not using the right tools... > >>>>>> nico(a)nctdevpuntnl (punt=.) > >>>>>> -------------------------------------------------------------- > >>>>> The HP3314A has a control panel, so it's not like you are buying a > >>>>> black box USB device from a Chinese company that won't exist in a few > >>>>> years. Black boxes can become bricks if the drivers are history. .... > >>>> How do drivers become history? With all my black boxes they came with > >>>> the box. Ok, I do not change operating systems at every whim some guys > >>>> in Redmond might publish. If a "new and improved" OS is not backwards > >>>> compatible with my legacy stuff I won't buy, I'll stay with the old OS. > >>>>> ... Think > >>>>> about all the ISA controlled items that have become bricks. ISA GPIB > >>>>> boards are valueable only for their trade in value with Nation > >>>>> Instruments. Anybody need a scsi drive? Now ethernet is another story. > >>>>> It doesn't need drivers. > >>>> Huh? You can buy plenty of brand new PCs with numerous ISA slots. > >>>> Regular quality or industrial stuff. And I'd venture to say that you > >>>> will find a similar selection 10 years from now. > >>>>> I've seen the similar Fluke or Tek function generator that cuts out at > >>>>> 11Mhz go for about $200. I think Joerg's issue is a lack of local > >>>>> geeks. ;-) In the bay area, these items are very common on the used > >>>>> market. Probably LA as well. > >>>> Yup, out here there's abosultely nothing going on of what you have in > >>>> the Bay Area in terms of electronics stores. IOW, out here there are > >>>> none left. > >>>> -- > >>>> Regards, Joerg > >>>>http://www.analogconsultants.com/ > >>>> "gmail" domain blocked because of excessive spam. > >>>> Use another domain or send PM. > >>> Drivers become history as the OS progresses. Or are you using your > >>> drivers from Windows for Workgroups while on Win 7? ;-) > >> Close: Until about 2005 I used a Logitech ScanMan on an NT machine. Only > >> seasoned computer users will remember it. It's the one on the right in > >> the picture: > > >>http://commons.wikimedia.org/wiki/File:Handscanner_01.jpg > > >> AFAIR WfW wasn't even out when I bought this and the software came on > >> floppies. Luckily I had made sure that the NT box could handle 5-1/4" > >> ... phzzzzzt ... done ... worked. Until its wheels fell off. > > >>> I still stick with the claim that the only black box that will live > >>> forever (or forever enough) is one using ethernet. I've got three > >>> perfectly usable ethernet appliances, one of which is at least 8 years > >>> old (forever in computer time). It's only 10mbps, but it is a linux > >>> bases print server that really don't need upgrading. Well, maybe when > >>> I go 10Gbps, I'll replace it. The other boxes are only 100mbps, but > >>> fine for the purpose. You put all the slow stuff on one router to act > >>> as a funnel to keep them from slowing down the fast ethernet. > >> Or, as Joel wrote, RS232. That bus is also forever and that's also what > >> the ScanMan device above utilized. > > >> -- > >> Regards, Joerg > > >>http://www.analogconsultants.com/ > > >> "gmail" domain blocked because of excessive spam. > >> Use another domain or send PM. > > > Well, yes and no regarding 232. First, they dropped the serial ports > > from most notebooks. They still have 232 on desktops, and of course > > you can add serial cards. The caveat is the device using 232 has to > > "agree" to handshake control, either XON/XOFF or the physical > > handshake lines. Many devices like GPSs and scanners do not have > > sufficient buffering to handle the "choppy" 232 modern PCs produce. In > > the dark ages (DOS), the program owned the port. You could even peek > > and poke. In more modern operating systems, the program has less > > control over the port and some programs that worked under win98 won't > > work under news OSs. > > Maybe I am lucky but all my RS232 works, including gear from the > mid-80's. The only issue is with very few non-standard devices that rob > power from the serial bus and can't live on the 6V or so that laptops > provide. > > -- > Regards, Joerg > > http://www.analogconsultants.com/ > > "gmail" domain blocked because of excessive spam. > Use another domain or send PM. Hey, all you have to do is 5V to be legal. The probably with 232 powered devices is there is no spec on how much power the 232 device should deliver. There is a spec on the DC load (input resitor of receiver), plus what you need for slewing. However, the good 232 devices try to limit the slewing, so they don't need as much drive. The whole serial mouse industry lived without a spec.
From: Joel Koltner on 11 May 2010 15:40 <miso(a)sushi.com> wrote in message news:7fb0f371-b563-4393-a451-9e921a1a7fe9(a)v29g2000prb.googlegroups.com... > The whole serial mouse industry lived without a spec. Early on, didn't some serial mice require external power adapters (wall warts)? You can get away with a lot at the 1200bps I seem to recal their using...
From: Spehro Pefhany on 11 May 2010 15:50
On Tue, 11 May 2010 12:40:28 -0700, "Joel Koltner" <zapwireDASHgroups(a)yahoo.com> wrote: ><miso(a)sushi.com> wrote in message >news:7fb0f371-b563-4393-a451-9e921a1a7fe9(a)v29g2000prb.googlegroups.com... >> The whole serial mouse industry lived without a spec. > >Early on, didn't some serial mice require external power adapters (wall >warts)? Anything is possible, but I can't remember any that did. There were serial port mice, and mice that used a proprietary ISA card. >You can get away with a lot at the 1200bps I seem to recal their using... There isn't much worst-case power at a serial port to operate the LEDs and other internal circuitry of the mouse. |