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N_Cook <diverse@tcp.co.uk>: Mar 06 09:02AM A neat cheap little 50m range (checked true) measurer, would it be possible to change the f crystal to hopefully f/3 or so and get 150m range. Assuming (looks possible) to split send and receive and enlarge the 15mm capture window to 150mm window. Also assuming I can identify which is the crystal and is not integral with the ASIC, not epoxied over anyway. Would the LCD likely become unreadable at 1/3 the original drive f. Accuracy would be worse but decimeter resolution over 150m would be fine

"pfjw@aol.com" <peterwieck33@gmail.com>: Mar 06 04:05AM -0800 MY concern would be whether or not the optics would support the longer distance. After all the trouble, you might have just a piece of landfill.   A Bosch device capable of that 150 feet is about US$60 these days, or less. And a cheaper off-brand device may be had for less than US$30.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Mar 06 12:33PM > A Bosch device capable of that 150 feet is about US$60 these days, or less. And a cheaper off-brand device may be had for less than US$30.   > Peter Wieck > Melrose Park, PA   Its optics I'm playing around at the moment with this 17GBP 50m (150ft) not poking around inside yet. Just in the process of boring/grinding a hole through a 150mm glass 3 dioptre magnifying glass to try passing the the transmit beam thru the centre and then larger capture area for the focussed received, to see how that works at 50m initially, ie how much darker a "reflector" would be the new minimum .

N_Cook <diverse@tcp.co.uk>: Mar 06 02:58PM On 06/03/2019 12:33, N_Cook wrote: > centre and then larger capture area for the focussed received, to see > how that works at 50m initially, ie how much darker a "reflector" would > be the new minimum .   So far , so good. 5mm hole ground in the centre and simply holding unit in line with the hole, can produce a 5m reading without forcing errors from its operational window , across the room. Now to mount in a rigid tube , to try outdoors, over 50m span.

Lucifer <LuciferMorningstar@bigpond.com>: Mar 06 12:40PM +1100 >on the one cpu but this is just basic troubleshooting.   >Odds are it's "something else" including a bad cpu but the battery and simm >placement is a good starting point.   I will check the battery and RAM placement. Thanks.   It has 6 x 2GB RAM cards. 3 for each CPU. Only 3 cards (6GB) show in System Profiler. I could have all 6 RAM cards for the one CPU but I'd really like to have both CPUs working.

bje@ripco.com: Mar 06 12:19PM > show in System Profiler. > I could have all 6 RAM cards for the one CPU but I'd really > like to have both CPUs working.   I've never seen one of those Xserves up close but have resurrected from the dead a few Sun servers. On Suns, the memory is more of a pool where is installed correctly, either cpu can grab as much ram as it needs, in other words, it's not dedicated to each cpu.   But who knows with apple.   I don't know if you have this or ran across it...   https://support.apple.com/kb/DL1428?locale=en_US   but it seems to contain the hardware diagnostics for that thing, at least the part of it called AXD EFI.   There are other versions, 3x104, 3x106 but one of them should work.   As the other guy (John?) mentioned, there could be a pair of simm looking things that are called VRM's, usually one for the cpu, the other for the ram bank, 4 all together (2cpu, 2ram). You can usually swap the cpu ones just to see if the off-led follows to the other one. If so, you know what to look for.   I can't find a diagram of that thing anywhere so only taking a guess there.   They are socketed like the simms and the only reason for that is again, on the Suns, they are changed if the cpu is upgraded. I don't know if they go bad, never had a bad one.   Good luck.   -bruce bje@ripco.com

Jeff Liebermann <jeffl@cruzio.com>: Mar 05 09:22AM -0800 On Mon, 4 Mar 2019 11:55:25 -0600, Ralph Phillips <ralphp@philent.biz> wrote:   >check all the tabs for a Maintenance button. I don't have a Brother, so >I can't verify here.)   >RwP   The maintenance tab looks something like this: <http://support.brother.ca/euf/assets/images/answers/images/Windows/8600Printpre012.jpg> Doesn't seem to do much. I just checked the driver for my Brother MFC-7860DW laser printer and the maintenance tab was missing. The tab seems to be only for inkjet printers, not lasers, but I'm not sure.   I'll be dealing with a office full of various Brother printers (all lasers) today, so I might be able to check if any of them have maintenance tabs.   Useful link: <https://www.ifixit.com/Device/Brother_Printer>     -- 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

Jeff Liebermann <jeffl@cruzio.com>: Mar 05 09:34AM -0800 On Mon, 4 Mar 2019 21:50:14 +1100, Clifford Heath <no.spam@please.net> wrote:   >Personally, I wouldn't keep a Brother. HP all the way.   I fix both Brother and HP laser printers. (The ink jets go to someone else or to the recycler). HP printer quality, serviceability, and parts availability vary depending on printer line and model. I've seen some that still function normally after 250,000 pages. However, on the latest models, I've seen them survive only 10,000 pages or less. Brother printers won't last as long but can be convinced to go 100,000 page with regular cleaning and maintenance. HP has better print quality. However, I can usually deliver 2-3 Brother printers for the price of one equivalent HP printer. Most (not all) Brother printers do NOT contain a refill prevention chip on the toner cartridge and can be found for about $15 on eBay. HP is somewhat more expensive, mostly because of the carts require a refill prevention chip. HP repair parts can easily be found online. Brother parts are more difficult to obtain.   I would give it an "HP most of the way" instead of "all the way". If you have a limited budget and you don't mind replacing the printer when it craps out, Brother is a good option. If you want it to last, HP is better. I have a small collection of cost of ownership spreadsheets for various models (that is in need of updating). For less than 5-10 years, Brother costs less to own. Beyond that, HP is cheaper. Between 5-10 years, they're about equal (if I buy eBay toner carts).     -- 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

Spare Change <noncompliant@notcompliant.zgq>: Mar 05 11:37PM -0800 On Mar 4, 2019, Mike S wrote   > I'm on my 2nd Brother laser printer and have never seen a service app to > my knowledge. Just out of curiosity, what is the intended use of the app?   It's called brmainte.exe and it is used to calibrate the laser when replacing it. Also serial number entry when replacing main PCB. A few other things.   From the maintenance manual:   https://imgur.com/uoyRqNt   Anybody know where brmainte.exe can be found?   Thanks.

Spare Change <noncompliant@notcompliant.zgq>: Mar 06 12:12AM -0800 > It's called brmainte.exe   There's also the maintenance.exe app:   https://imgur.com/VRKYnCM   Still looking for these apps...

Mike Coon <gravity@mjcoon.plus.com>: Mar 06 08:15AM In article <i2ct7eho34m6kinjbjvvo1ho5gmdcekmuo@4ax.com>, jeffl@cruzio.com says...   > I fix both Brother and HP laser printers. ...   In that case, can I ask your opinion about a problem with an HP color laserjet 3500. I fixed the problem it was handed to me with. (Sticky solenoid #4, determined by error message and explanation found on the web.)   But then find that it prints smeary. You can see smears that arise from the alignment patterns placed (but not meant to be printed) down each side of the transfer belt. And also from previoius printing. So maybe it is just inadequate gleaning of toner from the belt. But I cannot see how to fix that, short of a new belt unit. Since this is just a freebie being upcycled it does not warrant much, if any, expenditure...   A really dense colour picture looks great because the smears are hidden!   Cheers, Mike.

bob prohaska <bp@www.zefox.net>: Mar 06 02:19AM I've been given an old 2wire 1701HG ADSL modem/router, which I wanted to test as a possible spare for my aging Cayman 3546. The 2wire has a case with a vaguely bowtie-like profile, not the more modern rounded cigarbox shape of the later models.   The unit powers up and the lights make sense: Power flashes, then settles on steady green, LAN flashes at first then settles on steady green, DSL flashes a while, then turns red and eventually turns off since there's no DSL cable connected. The device was working when taken out of service, so I don't think it's fried, but it hasn't been used in at least five years.   I was able to do a factory reset, connect a computer and ping the default address of 192.168.1.254. However, a web browser pointed at that address brings up nothing useful. An old browser simply stops, a later version of chromium reported "connection refused". That seems odd, one would expect the controller to answer, even if DSL is down. Could it require a DSL connection to fire up the admin web server?   As a last resort I decided to examine the board for physical faults, like bad/cracked solder joints and leaky capacitors. Alas, the case has no visible means of assembly. I think it snaps together, but can't find any tabs that might release it.   If anybody's got a hint how to make further progress please let me know.   Thanks for reading!   bob prohaska

Jeff Liebermann <jeffl@cruzio.com>: Mar 05 09:07AM -0800 On Tue, 5 Mar 2019 08:22:00 -0000 (UTC), gregz <zekor@comcast.net> wrote:   >> on motherboards?   >My experience shows it dries up. Sure is messy. >Greg   Are you talking about "liquid metal" (gallium-indium) thermal paste? <https://www.thermal-grizzly.com/en/products/26-conductonaut-en> The paste offers an improvement in thermal conductivity, but with some issues. It rots aluminum heat sinks. It tends to run and drip when hot, shorting out everything it touches. It's difficult to clean up. It's expensive. I haven't tried liquid metal, but have cleaned up a motherboard and video card where the customer applied some.   W/m*K Diamond 1000 c-BN 740 (Cubic Boron Nitride) h-BN 600 (Hexagonal Boron Nitride) Silver 406 Copper 385 Gold 314 AlN 285 (aluminum nitride ceramic) Aluminum 205 Graphite 200 Carbon 150 SiC 120 Brass 109 Indium 86 Liquid Metal 73 (Indium-gallium-tin) ZnO 50 (zinc oxide) Al2O3 25 (aluminum oxide ceramic) Pastes 4.0 SilPad 2000 3.5 Circuit Works 1.84 Dow Corning 340 0.67   -- 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

Lucifer <LuciferMorningstar@bigpond.com>: Mar 06 12:43PM +1100 On Mon, 4 Mar 2019 14:51:11 -0800 (PST), John-Del <ohger1s@gmail.com> wrote:   >> on motherboards?   >I assume you mean heat conducting stuff? Way too viscous, but I don't >know if it will creep (prob not).   I used contact cleaner to fix a noisy volume control in a Commander telephone.

Pangopelsa2017@yahoo.com: Mar 05 04:46PM -0800 Good morning, Can you please send me the solution manual of Electronics a system Approach Neil sorey 5th? Thanks you for answering me.

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