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Micky <NONONOmisc07@bigfoot.com>: Nov 22 02:09AM -0500 Are all old-style low-end 900 Mhz speakers interchangeable?   The wireless speakers that sold new for $80 a pair in 1999, which I bought at a hamfest for iirc $20 a pair, are now for sale NIB for $400 a pair!! RCA WSP150 900 MHz Wireless Speakers   Well, there are cheaper ones that are used, but that's new in the box. What are the chances that I could buy a competitor, also 900MHz, and they will work with the transmitter I have now?? Or that their transmitter would work with my speakers??   I can wait for a bargain on the very same RCA speakers, but I'd hate to pass up other brands if they're really all the same. Especially if I see them at a yard sale or hamfest.   There's an Audio-Unlimited for sale that says "Auto tuning function for interference free reception utilizing Phase Loop Lock (PLL) technology automatically tuning in the optimal frequency." No transmitter included, The RCA speakers don't mention PLL. Does that mean they're not compatible? I read the wikip article about PLL but I still don't know.   Thanks for any help you can give.   (PLEASE DON'T SHOP FOR ME. MY GUMS HURT AND I'M NOT READY TO SPEND EVEN 60 RIGHT NOW.)     Background: I have two pair of the old ones, and one of the transmitters was bad, but I saw the vendor at the next big hamfest and he replaced it. Now I'm worried another one will fail. Also one speaker has very low range now. I put it in the bathroom, very close to the transmitter, but I can only do that with one of them. IOW, I need one or more spare transmistters and rcvr/speakers   They're stereo but I don't care about stereo, and I have one speaker in my bedroom, the kitchen, the basement, and the bathroom. Plus one spare, that I've used outside, but I had to borrow a wall-wart from another one. (I'll make up a wall-wart for the 5th one.)   It's great. I can listen to the same webradio station all over the house, especially since as I said in the other thread, I have trouble getting the two DC stations on real radios, but they're both on the web.

Micky <NONONOmisc07@bigfoot.com>: Nov 22 03:00AM -0500 Let me add that I can tell some won't work. Instead of a tuning knob they have Channel 1, 2, 3 (Maybe that's for PLL)   My current devices have a tuning knob on both the transmitter and the receivers, and I suppose I could tune to channel 1, 2, or 3, and then tune the other receivers to match, but that's looking for trouble.   Also, I suppose ???? if necessary some day, I could have two incompatible transmitters with their matching speakers. That should work, right?? but I still hope to avoid it.       On Sun, 22 Nov 2015 02:09:55 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:

makolber@yahoo.com: Nov 22 07:19AM -0800 If you don't need stereo, get a low Power fm transmitter and you can use Any ordinary fm radio to receive.

Jeff Liebermann <jeffl@cruzio.com>: Nov 21 10:04AM -0800 On Fri, 20 Nov 2015 18:26:39 -0500, M Philbrook   >Its amazing how you guys can find schematics to these things.   It's actually quite easy. Instead of searching the web, I do an image search. Photos, schematics, disassembly instructions, and such are much easier to find using images than text. You can text search for "xxxxx schematic" but schematics are rarely titles with the word "schematic" on the page.   If the photo is not quite what I want, such as Google image search find a thumbnail instead of a full size image, I use one of several reverse image searches to find the original: <https://support.google.com/websearch/answer/1325808?hl=en> <https://www.tineye.com> etc...     -- 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

M Philbrook <jamie_ka1lpa@charter.net>: Nov 21 01:19PM -0500 In article <92c15btimbeeccg6j9pqjfs9lhdb7ee07b@4ax.com>, jeffl@cruzio.com says... > <https://support.google.com/websearch/answer/1325808?hl=en> > <https://www.tineye.com> > etc...   I'll keep that in mind, Thanks   Jamie

Micky <NONONOmisc07@bigfoot.com>: Nov 21 01:42PM -0500 On Sat, 21 Nov 2015 13:19:22 -0500, M Philbrook >> etc...   >I'll keep that in mind, Thanks   >Jamie   Me too. Thanks.   One more question.   If I couldnt' find a power supply for the router, until I bought a new one, could I have just unplugged the wire from the DSL modem to the router and plugged it into the computer? The only thing I'm doing wirelessly now is print, and I don't print very often.   This idea kept popping in my head and then disappearing.

Jeff Liebermann <jeffl@cruzio.com>: Nov 21 11:28AM -0800 On Sat, 21 Nov 2015 13:42:11 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:   >One more question.   Sigh.   >one, could I have just unplugged the wire from the DSL modem to the >router and plugged it into the computer? The only thing I'm doing >wirelessly now is print, and I don't print very often.   Yes. 5V from the computer is the same as 5v from the Dlink wall wart. I have a cable with a Molex connector to adapt from the disk drive power connectors to some power plugs and cables that I hacked off some dead wall warts. This kludge makes a handy adapter cable for exactly what you're doing. I've used it when a customers wall wart dies, and I need something temporary until I can either fix or replace the original wall wart. If you can find the right size power plug, it should work.   >This idea kept popping in my head and then disappearing.   You probably have a black hole in your head. Black holes will suck both good and bad ideas equally so don't use the prevalence or disappearance of the idea as a figure of merit.     -- 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

MJC <gravity@mjcoon.plus.com>: Nov 21 08:12PM In article <92c15btimbeeccg6j9pqjfs9lhdb7ee07b@4ax.com>, jeffl@cruzio.com says...   > It's actually quite easy. Instead of searching the web, I do an image > search. Photos, schematics, disassembly instructions, and such are > much easier to find using images than text.   Sorry, I still don't follow: what are you using as your search criterion? I see how you might get disassembly instructions (or lots of sales pitches!) using a photo of the outside of the device, but schematics?   Mike.

Micky <NONONOmisc07@bigfoot.com>: Nov 21 03:19PM -0500 On Sat, 21 Nov 2015 11:28:39 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >wrote:   >>One more question.   >Sigh.   This is the price you pay for your earlier sarcasm.   >>router and plugged it into the computer? The only thing I'm doing >>wirelessly now is print, and I don't print very often.   >Yes. 5V from the computer is the same as 5v from the Dlink wall wart.   No, no 5v at all. I mean eliminating the router and going straight from the DSL modem to the network card in the computer. That's the default, isn't it? It's only been 8 years but I can't remember.   >should work.   >>This idea kept popping in my head and then disappearing.   >You probably have a black hole in your head.   Maybe I can get some Gorilla Tape. It's black too so it won't show that much.

Micky <NONONOmisc07@bigfoot.com>: Nov 21 03:26PM -0500 >> When I restarted, none of the lights on the wireless router went on, >> and an ohmmeter showed infinite resistance between the two prongs that >> plug into the wall. I had a surge, didn't I?   Apparently it just cooled off! >> http://www.ebay.com/itm/5V-2-5A-D-Link-JTA0302B-Power-Supply-Adapter/331703424856?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3D9a7781190364427ebe948ecf4421bb96%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D301720248001 >>....   >Bottom line...buy the new supply.   I did that. Should be here on Friday.   In the same way that planning for a vacation is almost as much fun as the vacation, it seems yesterday planning to repair the PS was 1/3rd the fun of actually doing it, plus I don't have a zener diode and even the parts I do have become a little hard to find.   >Problem with that one is the plug on the end is different from >most other router power supplies. Get the right one and be done with it.   They have the exact one, with the green plug showing in the photo. >Worst is electrocution? burning down your house? >For stuff connected directly to the line, >if you don't know what you're doing, keep it that way.   If I did it, I'd do it right. I know what I'm doing. Not knowing which part to replace doesn't mean I don't know what I'm doing.

M Philbrook <jamie_ka1lpa@charter.net>: Nov 21 04:54PM -0500 In article <che15bpl8f7hl7veoo3flifr2dp5dhj864@4ax.com>, NONONOmisc07 @bigfoot.com says... > router and plugged it into the computer? The only thing I'm doing > wirelessly now is print, and I don't print very often.   > This idea kept popping in my head and then disappearing.   No, you do not want to power off the USB port of the computer.   that supply is over 2 amps and most likely for good reason.   My router requires 1 amp minimum while the USB ports on most PC's are 500mA (1/2 amp)   You can have a USB port that has charging options, and also they do come with higher current but that is not the norm.   USB 3.x for the most part I understand have more powwer.   You are better off not chancing it.   Jamie.

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 21 05:04PM -0500 "Micky" <NONONOmisc07@bigfoot.com> wrote in message news:che15bpl8f7hl7veoo3flifr2dp5dhj864@4ax.com... > router and plugged it into the computer? The only thing I'm doing > wirelessly now is print, and I don't print very often.   > This idea kept popping in my head and then disappearing.   If you are talking about using the data cable and removing the router from the system, you should be able to do it with out any problems. I do it from time to time just to check the download and upload speeds.

John-Del <ohger1s@aol.com>: Nov 21 02:18PM -0800 It's a very common failure on supplies that run 24/7 to fail to restart after a cool down period.   Get any old hair dryer and give it a nice sauna for a few minutes, then plug it back in. If it starts, it's a high ESR cap in about 95% of the time.     On Saturday, November 21, 2015 at 3:26:29 PM UTC-5, Micky wrote:

Jeff Liebermann <jeffl@cruzio.com>: Nov 21 02:43PM -0800 On Sat, 21 Nov 2015 15:19:59 -0500, Micky <NONONOmisc07@bigfoot.com> wrote:     >No, no 5v at all. I mean eliminating the router and going straight >from the DSL modem to the network card in the computer. That's the >default, isn't it? It's only been 8 years but I can't remember.   That will work if: 1. If you're using PPPoE or PPPoA that require a login and password, it will work if those are saved in the DSL modem or in the computah. However, if you saved them in the router, you'll have to temporarily move them. 2. If you trust your unspecified operating system to be secure without the hardware firewall in the router. The DSL modem passes all ports, even if it has internal DHCP, so your computah's firewall does all the work. 3. If your DSL modem is independent of your router and doesn't require a hack saw to seperate them.   Can't you find a 5V power source and a power jack and do it correctly? This is a repair newsgroup, not a substitution newsgroup. A 5v 2A cell phone or tablet charger should work. Worst case is borrow the 5V from the PC. Do something, even if it's wrong.     -- 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>: Nov 21 03:01PM -0800 On Sat, 21 Nov 2015 20:12:59 -0000, MJC <gravity@mjcoon.plus.com> wrote:   >sales pitches!) using a photo of the outside of the device, but >schematics?   >Mike.   Ok, I'll walk you through it. First, I do a web search by product name and buzzword: <https://www.google.com/#q=d+link+JTA0302+repair> The first hit is the page I posted, which is more luck than finesse. However, we're looking for a schematic, so I click on the "Images" button for: <https://www.google.com/search?q=d+link+JTA0302+repair&tbm=isch> (Edited and shortened for clarity). Notice that several schematics magically appear in the results.   Let's pretend that you don't see the schematic that you're looking for. Click on ANY schematic. The search results will display the image with "Visit Page" and "View Image" button. However, we're gonna do something different. In the lower right are a series of thumbnails one of which is labeled "View More". Click that and you have pages and pages of similar schematics to sift through. <https://www.google.com/search?q=d+link+JTA0302+repair&biw=1397&bih=821&source=lnms&tbm=isch&sa=X&ved=0ahUKEwinr4_vy6LJAhUP8GMKHdV9COMQ_AUICSgE#tbm=isch&tbs=rimg%3ACZFH9IV11dHBIjg-oc7iGryprYGhMbJL3yU7s4yBEMwNeVqVguPgWuTPn2TyHae7nbkM1unm89X-59h8DZFv_1RHtmyoSCT6hzuIavKmtEVcoqqCFxshoKhIJgaExskvfJTsRfsuryv7U1zsqEgmzjIEQzA15WhH4nOkQgb56QyoSCZWC4-Ba5M-fET10TFIWWvIdKhIJZPIdp7uduQwR1e6tkiviKPIqEgnW6ebz1f7n2BETj_1Q1PRiNPCoSCXwNkW_19Ee2bEXI-6EAgeQ1c&q=d%20link%20JTA0302%20repair> Here's one in Russian that looks interesting: <http://masterpaiki.ru/goryachaya-shtuchka-d-link-ili-chinim-bp-jta0303e-e.html> Use Google Translate to convert it to English. <https://support.google.com/chrome/answer/173424?hl=en>   In case you haven't noticed, it really doesn't matter exactly what you use for a search. At a minimum, the model number. Notice that I chopped off the version suffix letter from the model number. Instead of "repair", you could use inside, schematic, disassemble, tear apart, bulging capacitor, etc. Whatever works to bring up images that are close. Your eyes do the rest.   -- 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

Micky <NONONOmisc07@bigfoot.com>: Nov 21 06:14PM -0500 On Sat, 21 Nov 2015 14:43:57 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >3. If your DSL modem is independent of your router and doesn't >require a hack saw to seperate them.   >Can't you find a 5V power source and a power jack and do it correctly?   I did already. It was just a question.   >This is a repair newsgroup, not a substitution newsgroup. A 5v 2A >cell phone or tablet charger should work. Worst case is borrow the 5V >from the PC.   You mean USB, or something on the mobo? I'd have to fix up a cable to do that.

Micky <NONONOmisc07@bigfoot.com>: Nov 21 06:16PM -0500 On Sat, 21 Nov 2015 17:04:20 -0500, "Ralph Mowery"   >If you are talking about using the data cable and removing the router from >the system, you should be able to do it with out any problems. I do it from >time to time just to check the download and upload speeds.   Good. It looks like "wire" was too vague a term. Two people thought I meant the power wire (because that's what we'd been talking about) and even you asked if really meant the data cable. Sorry.

Micky <NONONOmisc07@bigfoot.com>: Nov 21 06:38PM -0500 On Sat, 21 Nov 2015 14:18:35 -0800 (PST), John-Del <ohger1s@aol.com> wrote:   >It's a very common failure on supplies that run 24/7 to fail to restart after a cool down period.   >Get any old hair dryer and give it a nice sauna for a few minutes, then plug it back in. If it starts, it's a high ESR cap in about 95% of the time.   Aha. I saved a hair dryer I got somewhere just for testing electronics, but I had in mind testing for things that do NOT work when they're hot. I'll remember to test for those that work when they ARE hot. I could test this very PSU...oh, that's what you meant. (I thought you were giving general advice.)   I'll dig out the hair dryer and do that.   In ESR cap, what does ESR mean?

"Ralph Mowery" <rmowery28146@earthlink.net>: Nov 21 07:33PM -0500 "Micky" <NONONOmisc07@bigfoot.com> wrote in message news:rsu15bthseobsta8dkg05loaeu3299a6fs@4ax.com...   > In ESR cap, what does ESR mean?   Look up equivilent series resistance. In short it is a number that tells of the quality of the capacitor especially when used in switching and high frequency circuits.   Most any old capacitor will be ok for filtering out 60 hz in the old power supplies. When the switchers came out , the capacitors begain to fail . Checking on a simple capacitor meter will show the value ok, but they fail under the high speed/frequency high current usage.

Phil Allison <pallison49@gmail.com>: Nov 21 09:20PM -0800 Ralph Mowery wrote: > supplies. When the switchers came out , the capacitors begain to fail . > Checking on a simple capacitor meter will show the value ok, but they fail > under the high speed/frequency high current usage.   ** The ESR of an electro cap is mostly due to the conductivity of the liquid electrolyte used inside.   Modern, water based electrolytes have much better conductivity and hence lower ESR values compared to the same size caps made in the past and so can handle higher operating currents without excessive self heating.   Heat is the main killer of electros, whether from the local ambient temp or current flow in the cap or both. Luckily, the conductance of electrolytes improves with increasing temp which helps extend their life in SMPS.     ... Phil

Micky <NONONOmisc07@bigfoot.com>: Nov 22 03:37AM -0500 On Sat, 21 Nov 2015 21:20:02 -0800 (PST), Phil Allison >** The ESR of an electro cap is mostly due to the conductivity of the liquid electrolyte used inside.   >Modern, water based electrolytes have much better conductivity and hence lower ESR values compared to the same size caps made in the past and so can handle higher operating currents without excessive self heating.   >Heat is the main killer of electros, whether from the local ambient temp or current flow in the cap or both. Luckily, the conductance of electrolytes improves with increasing temp which helps extend their life in SMPS.   Thank you both.

makolber@yahoo.com: Nov 22 07:10AM -0800 If you have a dead open at the AC input, It could also be an open srge current limiter, thats the device in series w the fuse. It's supposed to be a high resistance when cold and change gradually to a low resistance As it heats.

1001firstlast@gmail.com: Nov 21 10:20PM -0800 I'm not getting any sound in the right ear piece of my headphones. I opened it up and tested the speaker by connecting it directly to an audio jack cable and it works. I also tested the continuity of the wires running from the left ear piece to the right, from one end of the external audio cable to the other, and of the wires running from the speaker to the circuit board. If I directly connect an audio jack to the wires at the circuit board end, the speaker works so I don't think it's a bad solder there. Does anyone have any other suggestions? This is my first repair project so no suggestion is too basic.

Micky <NONONOmisc07@bigfoot.com>: Nov 21 02:56PM -0500 This is just a question for curiosity.   I have a Magnavox 12 or 14" CRT tv with built-in VCR. I guess that means it's about 20? years old. Maybe it's generation can be judged by the fact it also gives the choice of English or Spanish when first plugged in.   I don't have the remote.   Often, when I push the Volume Down button, instead it lowers the channel, from 3 to AV. I think the on-screen volume display disappears then, so I use Channel Up to go back to channel 3, and then again try Volume Down, with the same result.   If I hold Volume Up for a while, Volume Down usually works, so this is not a major problem, but how is this problem possible?     Is this related: I have a Huaweii (sp?) smart phone that I dropped from 2 or 3 feet on to a ceramic tile floor. After that, when the phone is turned on, instead of the AT&T logo that used to show first, instead the first screen is all green background, with one big red and one big blue rectangle on it. But the next logo shows up and it starts and every feature that I try to use works. What happened? Did I bounce some electrons around.

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