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jurb6006@gmail.com: Mar 16 05:19PM -0700 I think you should resolder the board. When shit like this happens in one channel and then the other independently it is almost not going to be the power supply, which is usually the first logical guess. But in this case with both channels intermittent I think it has bad connections.   They may look good, especially with lead free solder, but the reason that you experience this the way you described could be due to thermal issues.   I am so disgusted with lead free solder that I quit. Think about that. I almost refuse to work on anything with it. It is too unpredictable and also it has corrosion issues you cannot see. Resolder it with 63/37 and cook it. I mean COOK IT. But look for the connections that might be possible for the problem, do not do all the connections. In fact if you have a floating iron you can do it while it is running and find the bad ones more easily. However, do not expect simple resoldering to fix it. You have to take all that lead free shit off and clean the connections, which means the board as well as the pins or whatever, and use the 63/37 on it.   If you do not want a recall that is.

dansabrservices@yahoo.com: Mar 16 07:33PM -0700 Isolate the problem first. Does the distortion change with a change in volume? I would guess that there is a transistor in the front end that is starting to fail because of heat. It doesn't take much.   You have an advantage here, one channel works as expected. Take some voltage measurements and compare left to right channels. Use a scope and see where the distortion starts.   IC431 (4580) might be a suspect. Follow the audio signal in both channels.   Let us know how you make out.   Dan

Bruce Esquibel <bje@ripco.com>: Mar 17 10:40AM > with both channels intermittent I think it has bad connections.   > They may look good, especially with lead free solder, but the reason that > you experience this the way you described could be due to thermal issues.     Hmmm, but isn't that receiver from the late 80's, early 90's?   Not sure the "lead free solder" problems would apply.   -bruce bje@ripco.com

Phil Allison <pallison49@gmail.com>: Mar 17 04:20AM -0700 Bruce Esquibel wrote:     > Hmmm, but isn't that receiver from the late 80's, early 90's?   > Not sure the "lead free solder" problems would apply.   ** The JVC RX807V is a thoroughly modern, home theatre, multi channel nightmare. Pb free solder is 100% guaranteed.   But it ain't all that bad.   IME, most Pb free stuff is far from impossible to deal with.   A bit of 60/40 on top of any dodgy looking joint works wonders ..         ... Phil

"David Farber" <farberbear.unspam@aol.com>: Mar 17 09:41AM -0700 Bruce Esquibel wrote:   > Not sure the "lead free solder" problems would apply.   > -bruce > bje@ripco.com   The date on the service manual is 1992 and the solder looks very shiny and easy to work with. I would say that it is not lead-free solder.   Thanks for your reply. --   David Farber Los Osos, CA

N_Cook <diverse@tcp.co.uk>: Mar 17 04:30PM Normal channel missing just mV of output, same with footswitch supposed operation, lead ch is fine. Seems to be a rare beast, any pointers to a schematic ? Uses 4x rc4558 opamps ,2x SJ3692 in PA, seems to use an opamp and FET for gating on and off "normal" gain channel. Swapped out the 4558s, as socketed, no change. Thought found prob on underside , one pot pin had never been soldered, just touching contact and some ring crack failures or dodgey looking at pots, but that was just the general crackly performance, clean ch still absent. o/p of one opamp is high, same with swapped version, goes to gate of the FET, which will be the next thing to investigate, if no schematic found. When last powered I did not think to see if the footswitch action gated the opamp o/p. Any other ideas?

Whiskers <catwheezel@operamail.com>: Mar 16 06:22PM > Later I was able to recharge the battery fully, use some and recharge > over and over up until now. Using a different cable. But if the > cable were bad, how to account for the first paragraph??   Could be a quirk of the battery controller in your phone. Or perhaps the 'small cubicle charger' (whatever that is) could supply sufficient current to keep the phone going, but not enough voltage to bring the battery to a full charge. I think a long thin cable might have enough resistance to have that effect, or one with a damaged conductor.   -- -- ^^^^^^^^^^ -- Whiskers -- ~~~~~~~~~~

Jeff Liebermann <jeffl@cruzio.com>: Mar 16 11:29AM -0700 On Thu, 16 Mar 2017 14:57:53 +0200, Micky <NONONOmisc07@bigfoot.com> wrote:     >Later I was able to recharge the battery fully, use some and recharge >over and over up until now. Using a different cable. But if the >cable were bad, how to account for the first paragraph??   Since the phone was on continuously, probably with full backlighting, and apparently while talking, it was drawing quite a bit of current from the battery. If your "small cubicle charger" was a gutless clone charger, that can only supply perhaps 0.5A at 5V to the charge controller in the phone, you could have been breaking even. If the total draw equals the charge current, then the phone is running off the charger, not the battery, and the battery SoC (state of charge) remains unchanged. You'll need to supply some more numbers to verify this. One of these will help with the charger part of the puzzle: <http://www.ebay.com/itm/222262460143>   However, you may have had a different problem. The constant 77% indication suggests that whatever is delivering this number (OS or some app) is hung. Since it recovered later, did you reboot the phone?   -- 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

jurb6006@gmail.com: Mar 16 05:06PM -0700 On top of what has been said, some chargers simply refuse to recharge when the battery is not low enough. Look at laptops, if you don't USE the battery the thing will stop recharging period. Some of them you have to take the battery out and unplug them to get them to charge again if you do not use the battery.   If the circuitry reads the battery as charged "enough" it may well refuse to charge. It depends on the make and model and type of battery.   Some of them you cannot just "top off" like an old car battery in a 1967 Chevy. They actually require cycling to work properly. So even if it causes you an inconvenience by dying a bit son, the point of the circuitry is to preserve the battery.   The technology is much better than it used to be but is still not perfect, especially when you require amp/hours out of a battery thinner than your credit card. Also, overcharging low quality batteries has been know to cause them to explode.   So when something like this happens, disconnect everythng, and if you cannot take the battery out, make sure to run it down. Watch ten movies on it or whatever, unplugged. Run it down to like 40 % and I bet it will charge. If not, there might be something wrong with it. (or the charger of course)

VanguardLH <V@nguard.LH>: Mar 16 08:09PM -0500 Jeff Liebermann wrote:   > indication suggests that whatever is delivering this number (OS or > some app) is hung. Since it recovered later, did you reboot the > phone?   How old is the battery? Maybe it never gets above 77% until you get a new battery.

Micky <NONONOmisc07@bigfoot.com>: Mar 17 09:01AM +0200 >>>over and over up until now. Using a different cable. But if the >>>cable were bad, how to account for the first paragraph??   >> Since the phone was on continuously, probably with full backlighting,   Yes.   >> and apparently while talking, it was drawing quite a bit of current   Yes.   >> total draw equals the charge current, then the phone is running off >> the charger, not the battery, and the battery SoC (state of charge) >> remains unchanged.   Yes.   >> indication suggests that whatever is delivering this number (OS or >> some app) is hung. Since it recovered later, did you reboot the >> phone?   I may have turned it off. It charges faster when off, though one friend of mine told me it only charges when on! Huh? I'm sure mine isn't different from his.   It doesn't charge very fast when on, even when the screen is black. But I know the lit screen runs the battery down far faster than with an unlit screen. So if the charger can keep pace when the screen is lit, why doesn't it charge faster when the screen is unlit.   Maybe Whiskers is right. The voltage of the charger is exactly or very close to the voltage of the battery, so the charger can also run the phone but it can't charge the battery.   How do those rechargers work, the size of a cigarette pack or so that charge when there is no outlet? Do they use a different battery that puts out more voltage**, or do they just even out the charge, like if you have an empty glass and a full glass, and you pour half a glass into the empty one? **If the charger put out more voltage it would take that much longer to recharge, and would never recharge from the little cube (maybe not cubicle) charger I brought and my friend also lent me. (I brought a bigger one too, that came with the phone, but mostly I'm using the laptop port..)     >How old is the battery? Maybe it never gets above 77% until you get a >new battery.   The battery was new with the phone last June or July, but as I said, later I fully charged it, to 100%. And I have done that at least 10 times since. Using a different cable.

Jeff Liebermann <jeffl@cruzio.com>: Mar 17 09:04AM -0700 On Fri, 17 Mar 2017 09:01:52 +0200, Micky <NONONOmisc07@bigfoot.com> wrote:     >I may have turned it off. It charges faster when off, though one >friend of mine told me it only charges when on! Huh? I'm sure mine >isn't different from his.   Well, there's an easy way to find out. Buy one of the various USB ammeters and measure what the charger is doing. <http://www.ebay.com/itm/222262460143> So, I tried it. I turned off my Samsung S6 phone and plugged in the stock Samsung 2amp charger. The screen showed a gray battery symbol with an ominous lightning bolt in the middle, which I assume means that it's either charging or self destructing. The gray battery symbol then filled up to 100% because the phone was already fully charged. The screen then announced that "This phone is capable of wireless charging". It would appear that the S6 is capable of charging when turned off.   >It doesn't charge very fast when on, even when the screen is black.   What is "it"? Maker and model please. If you plug a 0.5A or 1A charge into a phone that was designed to use a 2A charger, it will take much longer to charge.   >But I know the lit screen runs the battery down far faster than with >an unlit screen. So if the charger can keep pace when the screen is >lit, why doesn't it charge faster when the screen is unlit.   It does charge faster with the screen off. If the charger is delivering 0.5Amps, and the screen is drawing 0.4Amps, then the battery is only getting 0.1Amps.   >the little cube (maybe not cubicle) charger I brought and my friend >also lent me. (I brought a bigger one too, that came with the phone, >but mostly I'm using the laptop port..)   The LiIon external "I forgot to charge my phone" devices have one or more LiIon cells inside. Depending on the number of cells and feature list, a DC to DC inverter produces 5.0VDC at the USB connector. Circuitry on the PCB also take care of charging the LiIon batteries from a USB 5.0VDC charger. The voltage is always 5.0VDC.   To the phone, these devices look like a 1A or 2A USB charger. They supply 5.0VDC to the phone. The charge controller inside the phone decides how much current to suck out of the device, which is then used to charge the phone battery or run the phone.   I have a bunch of these that I inherited from various disreputable sources. They work well at moderating my erratic charging habits. None of them even come close to their advertised capacity (in mA-hrs).     >The battery was new with the phone last June or July, but as I said, >later I fully charged it, to 100%. And I have done that at least 10 >times since. Using a different cable.   I bought a bag of very thin USB to microUSB cables (in 10 assorted colors) on eBay to give to friends as holiday bribes. No problems or complaints yet. At the low price of these cables, if you suspect a problem, just replace it or try a heavier cable.   -- 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

jurb6006@gmail.com: Mar 16 04:53PM -0700 >"I don't use the sat radio in my car, but lots of people do. If I spent more time in the car I would pay for the subscription. But I do LOVE the nav, particularly the built in variety. If car hacking comes to be reality, I'll disable the microwave antenna and put my old Garmin back in service. "   Far as I can glean, the radio is not the problem. It is the problem detector, like if you get in a wreck. They hack in through that and can control your brakes and acceleration but ONLY if you have traction control and a few other things. What I read is that it happened through an ONSTAR system.   If I remember correctly it did not happen to a regular person, it was the company that had kids try to hack into it. It was not done to the average Joe on the street.   But it could. Unless they did some serious software modifications it certainly could. Newer cars can be different but the fact that a bunch of them run Windows is not really reassuring.   YOu might say they should be runnning Linux but the reason Linux is not hacked as much is because of its smaller market share it is simply not as big a target. It is open source, which means if someone wanted to take the time they could hack the shit out of it easier than Windows.   The MAC OS, well that is a possibility. They are not impervious to hacking but it can be done. If all the cars in the country ran it, it would become a target and gain the reputation of Windows in a very short time. These kids are good.   The only real solution is to keep the car offline. Just like some people still have old 98SE PCs running offline and burn CDs of the files they generate for transfer, when they are good and ready, to a modern PC. Only contact anythimg by choice. I would almost recommend the Garmin instead but only if you want them to know where you are. If you have a mistress or whatever, or like to party with some people of less than pristine character (by "their" standards) you might want to shut even that thing off.   People are getting used to being watched all the time, and I do not see that as a good thing.

ohger1s@gmail.com: Mar 16 06:35PM -0700 > >"I don't use the sat radio in my car, but lots of people do. If I spent more time in the car I would pay for the subscription. But I do LOVE the nav, particularly the built in variety. If car hacking comes to be reality, I'll disable the microwave antenna and put my old Garmin back in service. "   > Far as I can glean, the radio is not the problem. It is the problem detector, like if you get in a wreck. They hack in through that and can control your brakes and acceleration but ONLY if you have traction control and a few other things. What I read is that it happened through an ONSTAR system.   >snip>   My wife's car has ABS, traction and stability control as well as built in nav and sat radio (unsubscribed), but any system control influence the car can possibly have from the outside world would be through the nav/sat link. Removing the microwave antenna will take the car off line, assuming it can be remotely addressed at all (Ford Edge). It has no On Star (which I believe is cellular based?).   I would almost recommend the Garmin instead but only if you want them to know where you are. If you have a mistress or whatever, or like to party with some people of less than pristine character (by "their" standards) you might want to shut even that thing off.   Not worried about that.. I have no problems with surveillance cameras out of doors or any public place for that matter. In fact, since I'm one of those people who commit no crimes, I feel safer with them about. As far as the Garmin leaving a bread crumb trail in it's memory, that doesn't bother me in the least (and even those can be erased).

jurb6006@gmail.com: Mar 16 05:43PM -0700 >"Did it teach you how to wire the HV power supply in a high power TV transmitter?"   No   >"Have you ever worked with 10 KV shielded cable?"   Years ago, but not handling any real current.   >"He was not qualified to inspect anything bigger that a small store or one of the thousands of Condos in the area. He had no idea who the FCC was, or what a FCC Construction Permit was. He was as clueless about the FAA permit for the tower or the lighting requirements. "   Not surprising. Inspectors do not make what the people who do the real work make, I have found out why many times in the building trades. (but not transmitters)   >"...cursed me out and said he would be right back with a 'Cease and Desist Order to stop work on the new TV station. He never came back. "   Probably a rookie. Really. they give these guys authority without proper testing and vetting. That is the way i t works in this country and I am sure you are not all too happy about it either.   Know what else ? On a plumbing job I refuse to use teflon tape. I have personally proven it to be inferior to not only pipe dope, but even regular hand soap.   Someone lobbied for these regulations, just like any other. Government is deaf dumb and blind. they cannot do anything and that is why they are in government jobs.   There are exceptions but they are, of course exceptions. One was a very competent electrical inspector, they gave him the name "Ivan the terrible" because he really did his job. My work satisfied him even though I did not go through all the apprenticeship and all that, I learned from family. Most contractors dreaded his arrival to a job to inspect. And I have seen their work and some of it was downright dangerous. Other inspectors looked the other way but not Ivan Cucic. (the terrible) He did not want to see kids getting burnt in their beds n shit and I agree.   If you do something wrong like in electrical wiring, which is relatively simple, and it causes death or injury, you belong in jail. You should see how it is here. Licensed, bonded and insured mean nothing, all they do is pay off if you fuck up. I want it not fucked up. I never pursued that because I sold the job as "If I fuck up and your house burns down I lose my house, if the licensed, bonded and insured people fuck up an insurance people pay off. Who has the greater incentive to do the job right ? But I was never afraid of an inspection in fact I welcomed it.   I have seen things that will put hair on your chest, curl it and take it off in one fell swoop. Maybe we need a thread about that. And industrial too, why do they allow shared neutrals in commercial buildings ? And the reason that the shower goes hot when someone flushes a toilet is because it was not plumbed right, IMO. You have to not use the easiest method to avoid that. You take the toilet supply right off the main, way before it gets to the hot water tank. But they do not do that because it costs more money. So if you get scalded it is not their problem and if it is, they are licensed, bonded and insured so they suffer no loss.   And believe me, that is prevalent here. I have pulled extension cords out of walls.

jurb6006@gmail.com: Mar 16 03:20PM -0700 > Kinda sorry about that, no threat was warranted. I apologize.   BTW, this killed twelve people was fiction. And hopefully you had a look at to what I was replying. This was a rant, nobody can shut this down. Maybe the Russians could but not easily.

jurb6006@gmail.com: Mar 16 03:24PM -0700 > I have a beer now and then. Now, that the world's finally gone to 'H'. > (and even before then)   Well I do more than now and then. I can't stand how things are. Political correctness, then the liberals who fucked things up, and now Trump because they just HAD TO HAVE Hillary, why couldn't they just run someone good ?   The world is in alot of trouble, there is no doubt. Beam me up Scotty.

Jeff Liebermann <jeffl@cruzio.com>: Mar 16 10:55AM -0700 On Thu, 16 Mar 2017 08:19:39 -0000 (UTC), gregz <zekor@comcast.net> wrote:     >A/U is stranded center too. Rg58 is solid. Au cu difference seems to be >outer covering difference. >Greg   Oops, you're right. I stand corrected:   RG-58a/u (Belden 8259) <http://www.belden.com/techdatas/metric/8259.pdf> PVC jacket UL temp temp rating = 75C Attenuation at 1GHz = 70.5dB   RG-58c/u (Belden 8262) <http://www.belden.com/techdatas/metric/8262.pdf> Non-contaminating PVC jacket UL temp temp rating = 85C Attenuation at 1GHz = 74.8dB   So, different jackets, higher temperature rating, and less loss for RG-58c/u. Also, RG-58c/u appears to have a military designation (MIL-C-17, M17/155-00001), while RG-58a/u does not.   More: <https://abrind.com/faq/> Q: I see different jackets types advertised, what are the differences, and why I should care?   A:Jacket Types: PVC-I Polyvinyl Chloride (PVC), black (contaminating). Contaminating jackets will breakdown from sunlight (Ultra-Violet Resistant), and cannot be buried. The PVC-I is rated with a shorter life cycle than PVC-IIA. Suitable for low grade jumpers.   PVC-IIA Polyvinyl Chloride (PVC), black (non-contaminating). Non-Contaminating jackets will not breakdown from sunlight (Ultra-Violet Resistant), and suitable for direct burial without conduit. The PVC-IIA is rated with a twenty-year life cycle. The best all-around jacket. (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

Jeff Liebermann <jeffl@cruzio.com>: Mar 16 11:19AM -0700 On Thu, 16 Mar 2017 01:58:16 -0400, "Michael A. Terrell" >use a TV FSM as a 50 ohm RF millivoltmeter. Now, I have some precision >attenuators, and a Boonton 9200 RF Millivoltmeter ans different >feedthrough terminators.. :)   I initially did the same thing using various iron and ferrite toroid cores. They worked, but not if I wanted a really flat frequency response (+/-0.5dB) over many octaves of frequency range. I had a few adapters that I optimized for frequencies of interest, but getting it fairly flat from 1.5 to 30 MHz (marine bands at about 4.5 octaves) was rather difficult. Instead of fighting the problem, I switched to a minimum loss pad. The low frequency pads ended up inside Pomona aluminum boxes, while the microwave stuff was on microstrip stuffed into a box made from brass or unetched PCB material.   Actually, it wasn't quite a minimum loss pad. I worked out the numbers for a 50 to 75 ohm -6.0dB pad instead of -5.71dB, which made power and voltage scaling, measurements, and calculations easier.   One problem with minimum loss pads. They develop feet and walk away. I wasted about a day of company time building and characterizing a collection of about 20 attenuators for my own use. Within about 8 weeks, they were all gone, probably "borrowed" by my co-workers.   Hint: There's no such thing as a precision attenuator in a lab that works with transmitters. Eventually, they all get cooked. The best I could do was characterize what was left of the attenuator after someone accidentally transmit into it, and compensate for the changes in loss and impedance.   -- 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

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