- speaking of germicidal MV lamps, I have a question..... - 4 Updates
- Rice cooker, opening - 2 Updates
- weather instrument barograph ink resource and pen modification? - 2 Updates
- Ambient 7 Day Forecaster - 2 Updates
- Silly USB connection "repair" - 1 Update
| J-J <none@none.non>: Jan 26 03:09PM -0500 >> and capacitance? In the video, he is using 20 uF, but I think that's >> for a much larger bulb if I'm not mistaken. Thanks. > he uses a lightbulb as ballast to limit current. No cap that I saw. So the little blue round object at the bottom left of screen is not a capacitor? Sure looks like it with the two posts sticking up from it, but maybe not. |
| J-J <none@none.non>: Jan 26 03:11PM -0500 On 1/26/20 3:09 PM, J-J wrote: > So the little blue round object at the bottom left of screen is not a > capacitor? Sure looks like it with the two posts sticking up from it, > but maybe not. Never mind, I guess that's the plug for the incandescent bulb. It seems like that's all he has in series with the MV lamp then, an incandescent bulb to act as ballast. Any more details on this would be appreciated. |
| tabbypurr@gmail.com: Jan 26 01:34PM -0800 On Sunday, 26 January 2020 20:11:41 UTC, J-J wrote: > Never mind, I guess that's the plug for the incandescent bulb. It seems > like that's all he has in series with the MV lamp then, an incandescent > bulb to act as ballast. Any more details on this would be appreciated. the only other detail one could add is that the discharge is snaking. IIRC, and can't be sure, that comes from underrunning the discharge, which often affects lamp life. He makes the mistake of opening the window: let the ozone do its job. NT |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Jan 27 08:31AM -0800 > He makes the mistake of opening the window: let the ozone do its job. Sufficient atmospheric ozone to kill bacteria by exposure will pretty much destroy any rubber materials, attack many plastics, harm many plants and much worse. https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners Further to this, so-called "air cleaners" based on ozone are very similar to bug-zappers. They do not work, they can (and often do) cause harm and are generally worthless. Peter Wieck Melrose Park, PA |
| tabbypurr@gmail.com: Jan 27 06:14AM -0800 Asked to fix one of these, but am stumped at the start: how does one open it? There's no screw on the plastic base under the label, and the feet aren't removable. The only other accessible screws are the 2 on the rear side: removing the top one doesn't free the wraparound side at all, the lower one is the earth connection. Puzzled. https://ibb.co/Pt4nnvy https://ibb.co/8PScWFm https://ibb.co/nRm7RVH https://ibb.co/yQGwBrr https://ibb.co/DWhZWKR https://ibb.co/r2HWP7j The thing is o/c. It looks like a simple nonelectronic one, likely an easy fix if I work out how to open it! |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Jan 27 07:44AM -0800 http://www.buffalo-appliances.com/media/manuals/exploded%20diagram%20j300.pdf Looks like some sort of snap-fit system. Are those black dots on the feet holes, or little rubber bits? If holes, you may be able to release the feet through them. Landfill, or not, I expect that you will find replacement with a more serviceable model to be the expedient choice. Peter Wieck Melrose Park, PA |
| J-J <none@none.non>: Jan 27 09:04AM -0500 Picked up a 1972 Taylor barograph. This is a weather instrument with an electronic rotating drum. On the drum is taped a chart and, in combination with a "pen" (of sorts), barometric pressure is recorded. After a week, the charts are removed and replaced with a fresh one. I picked this up surplus with the hopes of reselling, but I am having trouble with two things: 1) sourcing a *cheap* slow drying ink, and 2) possible pen woes. I'm posting here because the rotating drum is, after all, electronic. In other words, it does not use a wind up key, but electronic mechanism and initial tests show that at least it appears to be rotating correctly and on time. However, just for testing, I cannot seem to find a low cost slow drying ink. There is "barograph ink", but it is quite expensive for a tiny amount. I know there must be alternative slow drying inks out there with different names at less cost that might be suitable. Any suggestions would be welcome here. Another thing I want to work on is the pen. The original is a tiny, triangular shaped stainless steel reservoir. A drop of ink is placed in the reservoir and this lasts until empty. There are alternative "pens" that are felt tipped, require no ink, and last up to two years... but again expensive. I'm wondering if I might be able to modify or use a standard felt pen from the store somehow in this application. Further suggestions appreciated. Thank you, JJ |
| tabbypurr@gmail.com: Jan 27 06:22AM -0800 On Monday, 27 January 2020 14:04:16 UTC, J-J wrote: > suggestions appreciated. > Thank you, > JJ The first question is what inky materials do you have on hand? If you can dissolve one in oil, paraffin, diesel or any mixture of those, great. Last time I did this I was using printer's ink plus paraffin. Inks applied in small enough amounts don't need to dry at all, the liquid part just soaks into the paper. I doubt an ordinary felt tip would work. You could sleeve the tip in plastic to try it, but I'm not optimistic. Most likely it'll run into the paper, and the paper will tear. Oh, I remember an ink experiment ... vegetable oil & powder toner. Soot is also usable but not nearly as convenient, as there is the issue of particle size. Anyway, why not use a biro? NT |
| "Paul Hovnanian P.E." <paul@hovnanian.com>: Jan 26 08:12PM -0800 Jeff Liebermann wrote: > <https://wiki.radioreference.com/index.php/Paging> > Are you near one of these cities? If so, I might be able to find the > location of the local paging transmiters using 929.6125 Mhz. I ran an FCC database search on the 929.0 to 930.0 MHz pager band, centered on Seattle (close enough to my location to cover reasonable transmitter sites). No sites are licensed for exactly 929.6125 MHz. But with a wide bandwidth front end, close enough might work. > connection. If you have a service monitor, try tuning the receiver > for best performance. Maybe replace the antenna with a length of coax > and RF connector so that you can attach an external antenna. There is no actual wire antenna on/in this thing. Basically just a little brass bar soldered to the reciever board (a one turn loop). Next time I go over to visit, I'll bring my unit and see if it loads as fast as theirs. It is interesting that, when I do get updates, it does a pretty good job, loading a 7 day forcast for 150 cities in the USA. But then it goes brain dead and the forcast data ages out. So it does work in fits and starts (without me having to smack it). When I power it down, the on-screen clock re-acquires the current time within half an hour. The pager company probably broadcasts a time signal for all its customers in a somewhat more reliable manner than the weather data. On a hopeful note: If the pager company is still maintaining their stuff, I live about a mile from a major hospital and medical complex. Doctors being a major customer for paging services, I seriously doubt that a viable paging company would let their service go to s**t in this area. I wish I had 900 MHz RF gear to do some testing. Most of my work is down around 60 Hz. Thanks for the RTL-SDR and Radio Reference links. I'll do some playing with those when I get a chance. -- Paul Hovnanian mailto:Paul@Hovnanian.com ------------------------------------------------------------------ Do not interfere in the affairs of dragons, For you are crunchy and tasty with barbecue sauce. |
| Jeff Liebermann <jeffl@cruzio.com>: Jan 26 10:46PM -0800 On Sun, 26 Jan 2020 20:12:27 -0800, "Paul Hovnanian P.E." >Jeff Liebermann wrote: >> Are you near one of these cities? If so, I might be able to find the >> location of the local paging transmiters using 929.6125 Mhz. Oops. I forgot to include the URL: <http://old.ambientdevices.com/cat/150cities.html> Looks like Seattle is (or was) listed as having coverage. >on Seattle (close enough to my location to cover reasonable transmitter >sites). No sites are licensed for exactly 929.6125 MHz. But with a wide >bandwidth front end, close enough might work. The FCC database is rather difficult to use. I don't want to ruin my evening by trying to find something in there. This might be of interest. See Pages 7 and 21 <https://labs.ece.uw.edu/funlab/funlab_CRdata/Seattle%20TVWS/radardata_v2.ppt> Looks like the Univ Washington Medical Center uses 929.6125. I doubt that UWMC is sending weather info on their paging system. It's probably coming from some other provider on the same frequency. Or, the previous provider of weather data sold the frequency to UWMC some time in the past. If I could find the license, I could lookup the history. More: <http://cloud.spok.com/coverage/LocalOne-way/SEA.pdf> >There is no actual wire antenna on/in this thing. Basically just a little >brass bar soldered to the reciever board (a one turn loop). Next time I go >over to visit, I'll bring my unit and see if it loads as fast as theirs. Is there a ceramic trimmer capacitor near the brass bar? Something that small for 900 MHz is going to have a rather high Q and require tuning to get it on frequency. I think you'll find the tuning adjustment to be rather critical. >re-acquires the current time within half an hour. The pager company probably >broadcasts a time signal for all its customers in a somewhat more reliable >manner than the weather data. Flex Time is usually sent once per minute and is typically off by as much as 30 seconds. I presume it varies with type of pager and transmitter maintenance. How your weather station handles time signals is unknown. >live about a mile from a major hospital and medical complex. Doctors being a >major customer for paging services, I seriously doubt that a viable paging >company would let their service go to s**t in this area. The hospital might be handling their own paging. See previous mention of UWMC. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
| N_Cook <diverse@tcp.co.uk>: Jan 26 07:59PM The annoying situation , due to thousands of make/break connection to a laptop and eventual wear. Where , despite cleaning of contacts, movement of the cable often breaks contact. A small piece of that protective slide of a 3in floppy disk, cut to L in cross section and wide enough to feed in the "gap" between USB line plug plastic slab of insulation and the metal shroud. So the short return part of the L is against the end of the plastic slab, just enough width to act as an end stop to loosing fully in the gap. May of course accelerate failure of the chassis socket part , but at 0.15mm thick metal , perhaps not, we'll see. -- Monthly public talks on science topics, Hampshire , England <http://diverse.4mg.com/scicaf.htm> |
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