reid@wrl.dec.com (Brian Reid) (09/12/90)
I want to buy a "strip chart recorder". I thougrht this was a very well-known device, but I just got back from my local electronics store (Fry's) and the staff there didn't even know what one was. So maybe I need to remind you that a strip chart recorder is a box that has an analog input, a roll of paper, a clock motor to drive the paper, and a pen. The pen wiggles up and down according to the signal applied to the analog input. Does anybody have any suggestions for stores in Northern California or else mail order places that might sell me such a device? Brian Reid reid@decwrl.dec.com
hbg6@citek.mcdphx.mot.com (09/13/90)
In article <1990Sep12.162833.15567@wrl.dec.com> reid@wrl.dec.com (Brian Reid) writes: > >I want to buy a "strip chart recorder". I thougrht this was a very well-known >device, but I just got back from my local electronics store (Fry's) and the > ......... >Brian Reid >reid@decwrl.dec.com Good luck! I had looked for quite some time for a strip recorder before I gave up and built one. A home brew recorder is fairly straight forward (unless you need to record thermocouples). Use calculator tape, and old clock motor, and build a little DC servo driver for the pen. A few years ago I started using a PC for data collection and gave up on recorders all together. John PS. the servo would be a lot simpler these days with the single chip servo systems I've seen around. ..................................................................... reply to 'from' address; hbg6@citek.mcdphx.mot.com NOT the 'sender' line address! Someday my sysadm will decide this is a 'real' problem. :-) ..................................................................... All opinions expressed are mine and not Motorolas, their loss. .....................................................................
brian@ucsd.Edu (Brian Kantor) (09/13/90)
Honeywell used to make some beautiful recorders. They were a joy to work on, too. I see Rustrak and other brands of strip-chart recorders from time to time in surplus stores, but I don't know offhand who stocks them new. The old-old Electronics Design Gold Book that I have lists over a page of places that carry such things new. I'd try a large surplus electro-junk store. If nothing nearby has any, there's always Herbach and Rademan in Pennsylvania, if they're still in business. The have everything. Edmund Scientific has one in an older catalog. Overpriced, as usual. - Brian
jgd@rsiatl.UUCP (John G. DeArmond) (09/13/90)
reid@wrl.dec.com (Brian Reid) writes: >I want to buy a "strip chart recorder". I thougrht this was a very well-known >device, but I just got back from my local electronics store (Fry's) and the >staff there didn't even know what one was. So maybe I need to remind you that >a strip chart recorder is a box that has an analog input, a roll of paper, a >clock motor to drive the paper, and a pen. The pen wiggles up and down >according to the signal applied to the analog input. Probably one of the cheapest "real" chart recorders is the Rustrak unit. This recorder uses pressure-sensitive ~2" chart and has a meter movement with a pointer that is struck against the paper by a "beater bar" at frequent intervals. The unit typically comes with a gear set that enables you to change the chart speed and the typical input is 0-1 madc. It should cost about $170 or so. Probably the easist source to deal with would be Omega Engineering (800) 826 6342. They'll take your credit card order and ship from stock. Ask them to send you their ~20 pounds of catalogs while you are at it. One of the most useful is their "Book of Books", a ~2" thick catalog of technical and reference books. If your environment can support it and you have a PC, you might also consider an inexpensive data acquisition card and some software like LabMaster. This combination will turn your PC and a printer into an intelligent strip chart recorder plus you can capture your data for further analysis. You should be able to get the combo for less than $600, hopefully much less. John -- John De Armond, WD4OQC | We can no more blame our loss of freedom on congress Radiation Systems, Inc. | than we can prostitution on pimps. Both simply Atlanta, Ga | provide broker services for their customers. {emory,uunet}!rsiatl!jgd| - Dr. W Williams | **I am the NRA**
mahaun@sactoh0.SAC.CA.US (Mark A. Haun) (09/15/90)
In article <1990Sep12.162833.15567@wrl.dec.com>, reid@wrl.dec.com (Brian Reid) writes: > > I want to buy a "strip chart recorder". I thougrht this was a very well-known > device, but I just got back from my local electronics store (Fry's) and the > staff there didn't even know what one was. So maybe I need to remind you that > a strip chart recorder is a box that has an analog input, a roll of paper, a > clock motor to drive the paper, and a pen. The pen wiggles up and down > according to the signal applied to the analog input. > > Does anybody have any suggestions for stores in Northern California or else > mail order places that might sell me such a device? I picked up mine at a local amateur radio swap meet. I think that digital recording is common enough now that most of the old-fashioned motorized units are not being sold new. My unit was made by the Esterline Angus company *many* years ago, but the paper drive system still works well. It uses color-coded gears which you can switch around to get 10 different drive speeds (5 "slow", 5 "fast"). And all of that for just $20. Unfortunately, I can't find a source of chart recorder ink for it :-( ! The ink/pen system basically consists of: 1) A long, narrow, rectangular tray which is to be filled with the right sort of ink, and a cover which snaps onto the tray. 2) A siphon tube which is lowered into the tray, and is connected to a very flexible rubber tube which leads to the pen mechanism. 3) A long, thin, metal pen arm, which has a tiny capillary tube inside for the ink to flow through. 4) An incredibly tricky pen balancing system to get the thing to slide smoothly across the paper (the arm is powered by the current being measured [+/- .5 ma]; there doesn't appear to be any sort of active-pen-drive system). The problem with normal ink is that it will evaporate from the pen tip whenever the machine isn't recording. As soon as the ink is absent from the tip, no more can be drawn out of the ink tray. The only way I know of to get the ink flowing again is to hook up a syringe to the pen tip through a small tube, try to get a good seal, then pull the syringe handle in a fast motion to pull ink through the system. The correct type of ink (I have a small sample, no more :-( ) doesn't seem to evaporate from the tip unless the machine is left turned off for a relatively long time (several days). Does anyone know where this ink can be obtained in small quantities? Esterline-Angus has a $100 minimum order :-( > Brian Reid > reid@decwrl.dec.com -- Mark A. Haun / 3445 Del Mesa Ct. / Sacramento, CA 95821 / Phone: (916) 488-2965 UUCP: {ames | apple | att | sun}!pacbell!sactoh0!mahaun | Amateur Radio: KJ6PC INTERNET: pacbell!sactoh0!mahaun@ames.arc.nasa.gov Amateur Pkt Radio: kj6pc@wa6nwe.#nocal.ca.usa -or- [44.2.0.56] on 144.93 Mhz