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Madness <policedept@thedonutshop.com>: Oct 10 08:25PM -0400 Replaced the belt on this deck (after spending well over an hour cleaning out the tar-like goo that the old one had gone to). Completely cleaned the head, trip-sensor & capstan w/ Q-tips & alcohol. Great, deck worked fine for about a week, but has now developed an annoying flutter (speed-variation) problem. Doesn't matter which cartridge I play, happens w/ them all. So, after looking at the rather-spartan service manual, I put a voltmeter across the motor to check for variations. The manual states that there should be 20VDC across it. Running it w/o the belt, it shows a steady 21.2V (so, no-load). But when I run a tape, I notice the meter changes a few tenths-of-volt whenever the speed varies (so w/ load, since I can cause the same under no-load by pressing down on the pulley). Which makes me wonder if the capstan needs a clean-out of old grease at its bearing. Would love to, but there's an E-clip *under* the flywheel the holds the whole assembly in place. Would love to know -- how-in-hell -- I'd remove that E-clip (the service manual gives no such information)? Anyhow, if anyone has worked on this or a similar Sony model (TC-228, 258, etc), could you please provide some insight?

stratus46@yahoo.com: Oct 10 11:24PM -0700 Lubrication issues? Sounds like the capstan might be wobbling in the bushings. If the belt turned to crud you can be certain the lubes are bad too. Sony is notorious for using lousy lubricants even in $100,000 broadcast machines.   G²

N_Cook <diverse@tcp.co.uk>: Oct 11 08:46AM +0100 On 11/10/2015 01:25, Madness wrote: > gives no such information)? Anyhow, if anyone has worked on this or a > similar Sony model (TC-228, 258, etc), could you please provide some > insight?   Is the wow cyclic? any repeat period could indicate where. What state the pinch wheel, hard,soft,flatted? can you invert it ,initially before replacing, and see if it makes a difference, also changing the applied tension by finger pressure. Are you sure you've removed all the ex-rubber black goo? it is annoyingly persistent stuff, it could trail in from somewhere unseen

Madness <policedept@thedonutshop.com>: Oct 11 11:12AM -0400 On 10/11/2015 3:46 AM, N_Cook wrote: > changing the applied tension by finger pressure. > Are you sure you've removed all the ex-rubber black goo? it is > annoyingly persistent stuff, it could trail in from somewhere unseen   I pretty sure that I've gotten all the goo out. Most had centered on the motor pulley & the flywheel. As for the "pinch wheel," those are built into each cartridge. Any idea on how I could remove the E-clip holding in the flywheel/capstan?

N_Cook <diverse@tcp.co.uk>: Oct 11 04:28PM +0100 On 11/10/2015 16:12, Madness wrote: > motor pulley & the flywheel. As for the "pinch wheel," those are built > into each cartridge. Any idea on how I could remove the E-clip holding > in the flywheel/capstan?   Piece of cotton tied to it and then a dart point or dental sickle probe

stratus46@yahoo.com: Oct 10 05:21PM -0700 NOBODY combines antenna and cable like that because the FCC doesn't like it but mainly because it doesn't work. Any signals on the same frequency will interfere and neither will be usable. It gets complicated because except for the channels numbered 2-13, the frequencies are _not_ the same between antenna and cable and with switched digital service on cable, the frequency for a given channel number may change day to day on the cable company. Many cable signals are scrambled and need the cable card to sort it out and are modulated QAM while Over The Air (OTA) are modulated 8VSB. The DATA (the TV signal riding on the carrier) is ATSC but tuning them in even if on the same frequency is different. You'll probably need to look up what the initialisms are all about.   ALSO to keep you confused, the OTA transmit frequency may NOT be the actual channel number. For example, in LA Channel 2 KCBS WAS analog an channel 2 until June 2009. Their digital channel was on channel 60 from 1998 until 2009. After the analog shutdown KCBS moved to channel 43. Data in the signal tells your TV to report that it is watching channel 2 even though it's on channel 43 (and when it was on channel 60)   I have one computer that is sourced by both my antenna and the cable company but they are separate tuner cards. The antenna card is a dual tuner Hauppauge 2250 and the cable unit is a Ceton InfiniTV6 cable card 6 tuner. They both function together seemlessly. That PC has a total of 8 tuners. The PC is connected to the TV by DVI-D / HDMI with the audio connected analog.   A 'Plant' would be cable company equipment.   B No   C No

amdx <nojunk@knology.net>: Oct 11 08:30AM -0500 On 10/9/2015 7:12 PM, micky wrote: > getting to the antenna even if there were a multiplexer or splitter > connecting the two signals, used to merge the two signal for a TV?   > Don't many people merge their cable and antenna signals like this?   I've just been through this wishing my TV had to antenna inputs, for antenna and cable, switchable by remote. It doesn't. So I hooked up a 3 position RF switch to switch between antenna and cable. It didn't work, when the antenna cable was attached to the switch the signal on the TV quit. Tried different inputs and a different 3 position switch, nothing worked. I then found a 2 position switch, when I installed the 2 position switch, it worked fine. I can only assume the 3 position switches did not have enough isolation between positions. The better solution for me is to use an 'OTA converter box' wired with an HDMI cable. Then just switch to different HDMI inputs with the remote. Mikek

veek <vek.m1234@gmail.com>: Oct 11 10:15AM +0530 Hi, I have some really old speakers Phillips DH415 that were gathering dust. I want to re-purpose them and use them with my TV/computer - i got to buy an Amplifier for them.   (here's an image: subwoofer+bass reflex+tweeter is what i suspect) http://imgur.com/a/Mt9Hw   I can't figure out what rating amp to buy.   If that's 20W PMPO x 2-speakers, then I need to buy: 30W RMS amp? That seems like not a lot of power and I don't remember this set being very loud. So is my assumption correct?   Are there any modern features I could look for in an amp. My TV is a Samsung 4003 720p and it has Component Ports for audio/video.

Phil Allison <pallison49@gmail.com>: Oct 10 10:08PM -0700 veek wrote: > http://imgur.com/a/Mt9Hw   > I can't figure out what rating amp to buy.   > If that's 20W PMPO x 2-speakers,     ** I reckon " Pm 20W " means "Power max 20 watts" .   > then I need to buy: 30W RMS amp?     ** That should be more than enough for TV and PC use.     ... Phil

veek <vek.m1234@gmail.com>: Oct 11 10:39AM +0530 I measured the case resistance (resistance at the jacks) using a multimeter and it shows 9 ohm, so i'm guessing these are 12 ohm speakers. I really need to figure out how much power I need to feed them.

jurb6006@gmail.com: Oct 11 12:00AM -0700 It ain't that critical. Thirty watts will bee fine. Whether it is PMPO, PMPILS, RMS or average doesn't matter. An old Marantz receiver maybe, or some small Sansui or something from the 1970s or so. They are out there for reasonable money. some have been restored and go for big bucks but most of them will run alright for a long time without a restore. They are all of ever eBay, as long as the seller says that it is tested and working. If you don't fix shit obviously do not go for the ones that say "for parts or repair".   And Craigslist. If the guy says "You can hear it run at my house" it is not a robbery. When you first walk in there, leave your money in your car. And if you buy tell the guy the money is in our car, he can walk out there with you if he wants but you will be right back cash in hand. But all that shit is for high end items, you want a 30 watt amp you should spend, on an unrestored but working mid fi amp maybe fifty bucks.   There are makes and models that command alot more bucks but most people do not need them.   In the audiophile realm, there are 30 watt amps that go for five figures. If you were looking for that, you would not have asked the question you asked. So I am thinking of those mid end fi things that me and my "rich" friends shunned, but really did sound good. You would probably be happy with an MCS, which was a JCPenny house brand with some of them maybe being built by Rotel or whatever. Or a Radioshack, which seem to be gaining popularity among mid audiophiles.   Really, 30, 40, 50, even 100 watt amp, when you hear it start to stress out, back of the volume or you fry the speakers.

Phil Allison <pallison49@gmail.com>: Oct 11 12:58AM -0700 veek wrote:   > I measured the case resistance (resistance at the jacks) using a > multimeter and it shows 9 ohm, so i'm guessing these are 12 ohm > speakers.     ** Says " 8 ohms " on the back of he twin cone speaker/woofer.   Try measuring right on the speaker terminal and check you meter.     .... Phil     I really need to figure out how much power I need to feed

ryan96se@gmail.com: Oct 10 05:46PM -0700 > (10,000 mfd, 10V) and it seems to be OK.   > Help!   > Also, Where can I get a schematic of this radio?   Check the speakers when you power it up. See if either on of them draw inward to outward. If so the main amplifier chip has failed. This will also give a loud 60hz hum. Bose will not sell you the chip but I found a youtube video of such a fix and he mentioned where he got it

jurb6006@gmail.com: Oct 11 12:09AM -0700 Do you realize the original question is from seven years ago ?   Do you realize someone did the same shit a little over a year ago ?

Clifford Heath <no.spam@please.net>: Oct 11 06:07PM +1100 On 10/10/15 19:16, Charlie+ wrote: > situation (even if you could hold onto the drill - but I havnt' > measured). > Otherwise the whole drill is for the bin! Its branded McKeller.   Like what I did here: <http://polyplex.org/electronics/ryobi_lifepo4/index.html>   Lithium Iron Phosphate (LiFePO4) are the go for drills, not Li-ion or LiPo. They're what the big brands use and despite lower voltage (nominally 3.4, 3.7 at max charge, not 3.7, 4.2 at max charge) and lower power density, they have better intrinsic safety than the others. Buy name-brand cells from a reputable supplier, or you'll almost certainly get crap or worse, repackaged dead cells pulled from old gear.   You need to bring out seven wires to a re-balancing connector. At first the cells may charge evenly, but they will age at different rates. After a year or three you'll need to rebalance them after every charge.   For up to six cells, go to Hobby King and get a Turnigy Accucel 6 charger and use it with an old laptop power supply. About $AU25.   I didn't bother with any protection but what is already in the A123 cells.   Clifford Heath.

Jeff Liebermann <jeffl@cruzio.com>: Oct 10 10:06AM -0700 On Sat, 10 Oct 2015 11:06:13 -0400, "(PeteCresswell)" <x@y.Invalid> wrote:   >Before I unsolder this thing and just jump the two rightmost pins   The "on" contact traces are already jumpered on the PCB. Look at your photo.   >maybe mess something up.... can anybody comment on the possible roles of >the other pins ?   >https://picasaweb.google.com/108149798664924808733/Misc#6204033735361530914   DPDT switches are commonly used for power on/off because with 6 pins, the switch is solidly mounted to the PCB. It will not wiggle side to side as it would if it were a SPDT (3 pins). Also, manufactories like to use as many of the same parts as possible. It doesn't make much sense to inventory SPST, SPDT, DPST, and DPDT switches, when a DPDT will do the job of all of these. Lastly, if there is any inrush current when turning the device on, distributing the current through two paths saves some wear and tear (or arcing) on the contacts.   -- 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

"(PeteCresswell)" <x@y.Invalid>: Oct 10 04:15PM -0400 Per Jeff Liebermann: >The "on" contact traces are already jumpered on the PCB. Look at your >photo.   That would be the two middle contacts, right? -- Pete Cresswell

micky <NONONOmisc07@bigfoot.com>: Oct 10 04:51PM -0400 In sci.electronics.repair, on Sat, 10 Oct 2015 16:15:23 -0400, >>The "on" contact traces are already jumpered on the PCB. Look at your >>photo.   >That would be the two middle contacts, right?   The two middle ones are connected and the two to the right are connected, afaict. So both poles of the switch turn on simultaneously, or very very very nearly so.   What problem is the switch causing? Are you not sure it's on when it's supposed to be on? Remove the power and measure the voltage between the middle two contacts and the right ones.   It should be zero. If it's zero, you can then measure the resistance between them, the middle two contacts and the right ones. It should be about zero when the switch is closed and very high when the switch is open. If it's not, post back. I don't know enough about circuitry to insist that all my expected conditions be true. For example, iirc some switches have a capacitor across them, to reduce sparking I think. If the capacitor were to short, the resistance even when open would be low.     From the first post: >Before I unsolder this thing and just jump the two rightmost pins - and   Even if in another situation you needed to jump the two pins, I'd see no need to unsolder the switch. Well, unless you were afraid the presence of the switch woudl mislead someone, or you needed to take it, and not just its dimensions, with you to buy a new one.

"(PeteCresswell)" <x@y.Invalid>: Oct 10 06:02PM -0400 Per micky: >What problem is the switch causing? Are you not sure it's on when >it's supposed to be on? Remove the power and measure the voltage >between the middle two contacts and the right ones.   This will be awhile. I need to find some reliable probes for my el-cheapo voltmeter.... the ones I am trying to use are not getting it for such small targets as the pins on the bottom of that board.   The device in question (a automobile dashcam) is supposed to start up automagically when 12 v is fed to it and the switch is on.   The switch is always on.   But starting a few weeks ago, it was coming on sometimes, not coming on other times.... and now it is never coming on.   I *think* am getting 12v on the power source... so my guess was that the switch had failed.   Now I am not so sure about the power source because of my issues with the meter and it's probes.....   Stay tuned... -- Pete Cresswell

micky <NONONOmisc07@bigfoot.com>: Oct 10 07:37PM -0400 In sci.electronics.repair, on Sat, 10 Oct 2015 18:02:26 -0400, >>it's supposed to be on? Remove the power and measure the voltage >>between the middle two contacts and the right ones.   >This will be awhile.   I know that feeling. Some of my projects have lead times of 5 or 10 years.   > I need to find some reliable probes for my >el-cheapo voltmeter.... the ones I am trying to use are not getting it >for such small targets as the pins on the bottom of that board.   In the picture, the board is leaning against a keyboard, so I can tell how big it is, and ...any probes should work, unless your hand shakes.   I used to make, and now I buy, jumper wires with alligator clips on each end. A package of 10 light weight, 18 gauge, is about 3 dollars. Heavy weight, 16? I havent' seen lately but I rarely need that.   And I clip one end of the jumper to the black probe, and the other end to what looks like a ground in the device. Or a leed or spike of solder that can be clipped to. Especially important with hot circuits so I can concentrate on where the red probe goes.   But I don't think that would actually work here   >The device in question (a automobile dashcam) is supposed to start up >automagically when 12 v is fed to it and the switch is on.   So at most, if unplugged, not especially this device, it could have less than 12 volts in a capacitor and it can't hurt you, but others here could tell you if a 12 volt cap could discharge through an ohmmeter and damage it. But I'm sure there are no big caps on this board. >other times.... and now it is never coming on.   >I *think* am getting 12v on the power source... so my guess was that the >switch had failed.   The switch itself, Not especially likely IME. For one thing, the switch is two pole, like two parallel switches. They'd both have to fail.   Before you do anything more, look for cold solder joints or solder that has cracked. First at the switch. If there is a crack around a pin, between the pin and the solder, especially if it goes all the way around, that's very bad. And sometimes the solder is stuck to the pin but cracked in the middle of the solder, If there's a trace underneath, I guess that's not so bad. But I'd remelt and resolder anything that looks like that. Especially on a switch, which is not a transistor.   But the advantage of using a meter from the beginning is that if you found the solder at the switch was bad, and now it's good, you know you fixed some, likely all of the problem. If you resolder now, measure only afterwards, you won't know if you fixed anything.   If you're bad at soldering, I'd avoid resoldering transistor leads, for fear of damaging the transistor with heat. You want to melt the solder quickly and quickly remove the iron so it cools. If you're good at all this   I hate to skip using a meter. It answers questions. But if I were McGiver and my life depended on it, and all I had was a ball of twine and a soldering iron, I'd skip the meter for now and solder a little piece of wire across the bottom two connectors. The bottom right has a trace. Not sure which of the left points have one. Maybe the top. If the top, make the wire twice as long and bend it so it goes to the top left too.   >Now I am not so sure about the power source because of my issues with >the meter and it's probes.....   >Stay tuned...   Harbor Freight has good enough meters for 5 dollars. Lowes and Home Depot have them for under 20. I've lost track of Radio Shack though I know it still has 1700 stores open, though their webpage doesn't have a catalog yet. Plus if you have a meter and probes now, I can't imagine what is wrong with the probes. On a low voltage like that, and disconnected to boot, so you can't hurt yourself, you don't even need probes. You could just use the wire, stipped back 1/8" and use the wires at the end.

"Rheilly Phoull" <rheilly@bigslong.com>: Oct 11 08:17AM +0800 "(PeteCresswell)" wrote in message news:bh2j1bdmlv5ju5djcqgb5bloddtv8m12ib@4ax.com...   Per micky: >What problem is the switch causing? Are you not sure it's on when >it's supposed to be on? Remove the power and measure the voltage >between the middle two contacts and the right ones.   This will be awhile. I need to find some reliable probes for my el-cheapo voltmeter.... the ones I am trying to use are not getting it for such small targets as the pins on the bottom of that board.   The device in question (a automobile dashcam) is supposed to start up automagically when 12 v is fed to it and the switch is on.   The switch is always on.   But starting a few weeks ago, it was coming on sometimes, not coming on other times.... and now it is never coming on.   I *think* am getting 12v on the power source... so my guess was that the switch had failed.   Now I am not so sure about the power source because of my issues with the meter and it's probes.....   Stay tuned... -- Pete Cresswell   For the probes use a file and sharpen the ends to a fine point. This helps for small points and pierces any coatings too.

"(PeteCresswell)" <x@y.Invalid>: Oct 10 08:47PM -0400 Per micky: >than 12 volts in a capacitor and it can't hurt you, but others here >could tell you if a 12 volt cap could discharge through an ohmmeter and >damage it. But I'm sure there are no big caps on this board.   I'll start in on the cold/cracked joint inspection next.   I have no clue what constitutes a big cap but, FWIW, this cam is designed to run for a certain period of time after the 12v external power has been removed - and they do that by using 2 capacitors instead of a rechargeable battery. Each capacitor is about 3/4" long and 5/16" in diameter. This is supposedly a higher-end feature because the caps will not wear out like rechargeable batteries will. -- Pete Cresswell

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