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"Arfa Daily" <arfa.daily@ntlworld.com>: Aug 10 05:33PM +0100 "Phil Allison" <pallison49@gmail.com> wrote in message news:fa32623b-8488-42c9-93ae-e4db0ae15e34@googlegroups.com...   > ... Phil   Today, having pulled all of the cabling out of the way, It was possible to see where the secondary wires spaded onto the lower PCB, and there was just enough room between the board stack and the cabinet side to mark them, and pull them with a pair of long-nose pliers. I then shorted the blown-out thermistor, and hooked up the variac again. Same as before. 20 volts of input, and the variac is grunting fit to bust, so it does look like the transformer primary is shorted turns, as that's now the only thing connected. So now a case of seeing if we can get the tranny and inrush thermistor, and more to the point, at what price ...   Arfa

Tim R <timothy42b@aol.com>: Aug 09 02:13PM -0700 On Sunday, August 9, 2015 at 12:21:40 AM UTC-4, Trevor Wilson wrote:   > **Since you have declined to provide any useful information, I doubt you > can be helped. A model number would be nice. Some old amps are well > worth resurrecting. Some are not. Given that yours is "old and extremely   Sorry about that, the model number was on the back.   It's an Onkyo TX-3000. I bought it for $5 at a thrift store years ago, and still remember carrying it to the car several blocks away.   I just looked it up, the weight is 11.4 kg. The date is given as 1981, which may make it almost 35 years old.   I haven't opened it up to look yet.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Aug 10 09:05AM +1000 On 10/08/2015 7:13 AM, Tim R wrote:   > I just looked it up, the weight is 11.4 kg. The date is given as > 1981, which may make it almost 35 years old.   > I haven't opened it up to look yet.   **I guess our definition of "heavy" is very different. 11.4kg is not heavy. 50kg is heavy. Either way, your Onkyo is an attractive, retro-styled receiver. Keep an eye on eBay for typical selling prices. That will provide an indication as to the viability of repair. Your first option should be to obtain a service manual, or schematic and perform the usual fault-finding process.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Mark Zacharias" <mark_zacharias@labolgcbs.net>: Aug 10 06:00AM -0500 "Trevor Wilson" <trevor@SPAMBLOCKrageaudio.com.au> wrote in message news:d2q4njFrdq6U1@mid.individual.net...   > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus   The OP has no technical expertise. Other than the 4 amp fuses on the rear of the unit, his chances of fixing it himself are low.   Having said the obvious, if there is sound at that channel of the volume control, the fault is most likely an output IC (STK0050II) or driver IC (STK3062).   New old stock replacements are rare and Chinese counterfeits are likely to perform poorly if at all.     Mark Z.

all2001@spambog.com (Wolfgang Allinger): Aug 10 07:31AM -0300 On 10 Aug 15 at group /sci/electronics/repair in article 55c8844e$0$3646$4c5efc6d@fastusenet.org >driver IC (STK3062).   >New old stock replacements are rare and Chinese counterfeits are >likely to perform poorly if at all.     Some amplifier have Relais just to suppress the PWRon `plopping`.   Find out, if the Onkyo has it.   The contact (material) often is bad selected, designed, dirty or broken...   Knocking these Relais while powered with the grip of a screwdriver from different direction just to see if gives some scratching noise.   Some relais may be opened easily and press/move/clean the contacts. Or find out the layout position of the contact and bridge them for the faulty channel.     Saludos (an alle Vernünftigen, Rest sh. sig) Wolfgang   -- Wolfgang Allinger, anerkannter Trollallergiker :) reply Adresse gesetzt! Ich diskutiere zukünftig weniger mit Idioten, denn sie ziehen mich auf ihr Niveau herunter und schlagen mich dort mit ihrer Erfahrung! :p (lt. alter usenet Weisheit) iPod, iPhone, iPad, iTunes, iRak, iDiot

Tim R <timothy42b@aol.com>: Aug 10 05:27AM -0700 On Monday, August 10, 2015 at 7:00:33 AM UTC-4, Mark Zacharias wrote:   > Having said the obvious, if there is sound at that channel of the volume > control, the fault is most likely an output IC (STK0050II) or driver IC > (STK3062).   This is true. I can do some minor component replacement but am lost troubleshooting, so the chances of finding the right component are small.   Just to be clear I've described the problem, here is what happens: sound comes out of one side of the speaker connections but not out of the other, regardless whether I push the mono or stereo utton, regardless whether I use speakers A or speakers B.   My question revolved around whether an Onkyo is worth fixing (sounds like yes), is easy to fix (sounds like no) and whether a 35 year old piece of equipment has multiple other parts at the end of life.

dansabrservices@yahoo.com: Aug 10 05:35AM -0700 > My question revolved around whether an Onkyo is worth fixing (sounds like yes), is easy to fix (sounds like no) and whether a 35 year old piece of equipment has multiple other parts at the end of life.   This should be a simple fix. Where are you located? There are some of us that would be willing to repair it for you I'm sure at a reasonable cost.   Dan   P.S. I have NOS STKs available if the ones listed up thread are accurate.

Tim R <timothy42b@aol.com>: Aug 10 09:21AM -0700 > > My question revolved around whether an Onkyo is worth fixing (sounds like yes), is easy to fix (sounds like no) and whether a 35 year old piece of equipment has multiple other parts at the end of life.   > This should be a simple fix. Where are you located? There are some of us that would be willing to repair it for you I'm sure at a reasonable cost.   Central Virginia, south of Richmond.

Jeff Liebermann <jeffl@cruzio.com>: Aug 09 09:53AM -0700 >Have been using a Radio Shack Mini Amplifier Model No. 277-1008 >for many years to help out a person with a disability. >Really important for them   It's still in the catalog: <http://comingsoon.radioshack.com/radioshack-mini-audio-amplifier/2771008.html>   >As no longer a R/S, have been trying to find who might actually >make/made this unit, and/or who might still be carrying them.   Rumors of Radio Shack's demise have been greatly eggagerated. Many stores are still open as is their mail order business.   >Anyone have any ideas where I can purchase a few.   Online. See above URL.   Or eBay at outrageous prices: <http://www.ebay.com/sch/i.html?_nkw=277-1008>   -- 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>: Aug 09 09:57AM -0700 On Sun, 09 Aug 2015 09:53:14 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >>make/made this unit, and/or who might still be carrying them.   >Rumors of Radio Shack's demise have been greatly eggagerated. Many >stores are still open as is their mail order business.   Oops. Looks like the mail order business isn't there any more. However, the store search found several stores that allegedly have it in stock.     -- 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

Klay Anderson <klay@klay.com>: Aug 09 10:08AM -0700 I use these for simple hearing assist. No volume controls but nice. http://www.smokeyamps.com/

"Ian Field" <gangprobing.alien@ntlworld.com>: Aug 09 08:16PM +0100 "Bob" <rgsros@notme.invalid> wrote in message news:mq8011$s61$1@dont-email.me...   > As no longer a R/S, have been trying to find who might actually > make/made this unit, and/or who might still be carrying them.   > Anyone have any ideas where I can purchase a few.   Another alternative is an amplified PC speaker, if the input impedance is too low just add a JFET source follower. You can use the volume pot as rhe source resistor, then all you need is a gate-leak resistor and input coupling capacitor.   Most types run off a wall-wart, but you can get them with an internal battery compartment.   A couple of years back; a columnist in one of the hobby magazines mentioned a speaker amplifier unit for Walkman style gadgets in the £1 shop - needless to say, all gone by the time I got there. Apparently the unit had a pair of small speakers driven by a TDA2822.   Ready made amplifiers aren't exactly rare, back in the 70s - 80s, any number of component stockists advertised small amplifiers (just a populated PCB) around the 250mW mark.   An old vest pocket transistor radio is a good candidate for the JFET modification - but those are often collectibles, such vandalism would horrify some people.

"Dave M" <dgminala4444@mediacombb.net>: Aug 09 02:24PM -0500 Search for Personal Amplifier on Amazon.com. There are several there that have builtin microphones, but use earphones instead of a builtin speaker. Prices are generally under $30.   My dad used one of those amplifiers for several years before his death. Sorry, but it's long gone now, else I'd be glad to send it to you.   If you're into electronics kits, you might check out the kit at http://www.bgmicro.com/KITMK136.aspx. Looks interesting, small enough to put into a small box with a battery and carry in your shirt pocket. And it's STEREO!!   Cheers, Dave M       Bob wrote:

"Ian Field" <gangprobing.alien@ntlworld.com>: Aug 09 08:35PM +0100 "Dave M" <dgminala4444@mediacombb.net> wrote in message news:HpOdnWNPpZJqNVrInZ2dnUU7-eWdnZ2d@giganews.com... > http://www.bgmicro.com/KITMK136.aspx. Looks interesting, small enough to > put into a small box with a battery and carry in your shirt pocket. And > it's STEREO!!   A stereo unit can be a PITA if you only want mono, but if its a common chip and not already BTL, most have a sample circuit for a BTL amp included in the appnote.

Michael Black <et472@ncf.ca>: Aug 09 09:29PM -0400

jurb6006@gmail.com: Aug 09 10:17PM -0700 >But now, the volume control may not be a suitable marker, the control may >not be attenuating the audio signal, but varying a DC voltage to control a >stage that is controlling volume."   Or a rotary encoder going to the microprocessor.

MJC <gravity@mjcoon.plus.com>: Aug 10 10:33AM +0100 In article <d42bdaa5-2856-4d16-a0d4-ef46574afb4b@googlegroups.com>, jurb6006@gmail.com says...   > >But now, the volume control may not be a suitable marker, the control may > >not be attenuating the audio signal, but varying a DC voltage to control a > >stage that is controlling volume."   > Or a rotary encoder going to the microprocessor.   I rather like my old JVC hi-fi in which the remote control (which unfortunately was stolen!) causes a motor to turn a nice large volume control knob, on which a flashing LED shows what setting it has reached. Much better than a digital display!   I have only recently given up using my Nikko TRM 40LA amplifier which I bought second hand from an ex-pat colleague on a business trip to NY City in the early 1970s. Although it was fairly heavy (with of course a large power transformer) it came back to the UK embedded in my dirty laundry in my suitcase. Since the instruction booklet included a schematic I tweaked some circuits as I saw fit...   Mike.

"Ian Field" <gangprobing.alien@ntlworld.com>: Aug 10 05:20PM +0100 "Michael Black" <et472@ncf.ca> wrote in message news:alpine.LNX.2.02.1508092125250.25787@darkstar.example.org... > But now, the volume control may not be a suitable marker, the control may > not be attenuating the audio signal, but varying a DC voltage to control a > stage that is controlling volume.   Most of the older shirt pocket items had about 4k7 volume pot, usually this is too low for most signal sources you might want to patch into it.   My solution is to build a JFET source follower onto the input, you can use the pot as the source resistor, in front of the JFET you only need a gate-leak resistor and coupling cap.

JW <none@dev.null>: Aug 10 08:00AM -0400 On Sat, 08 Aug 2015 20:11:50 -0700 Jeff Liebermann <jeffl@cruzio.com> >smoke, but the flames went out too quickly. Read about what goes into >a bee keepers smoker for clues: ><http://www.dave-cushman.net/bee/smofuel.html>   How about using incense?

Jeff Liebermann <jeffl@cruzio.com>: Aug 10 08:12AM -0700 >>a bee keepers smoker for clues: >><http://www.dave-cushman.net/bee/smofuel.html>   >How about using incense?   I haven't tried incense but I suspect it will not produce enough visible smoke.   Also, since the machine under test is usually borrowed, methinks the owner might not appreciate having his machine internally coated with a layer of smelly oil. I had that problem when I used some of the pine kindling I save for starting my wood burning stove. The sap (creosote) was carried along with the smoke and made the case reek like a pine tree. Fortunately, most of it condensed near the air intake, so all I had to do was solvent wash the grill work and Dell's one big case fan. What you want is a finely divided ash, not a smelly or oily glue.   Sigh. I guess they don't teach combustion, bomb making, and arson in the skools any more. We had "burn baby burn" while I was in college, but I guess later generations were too busy burning incense, getting stoned, and fighting smog to bother learning about rapid oxidation. Very sad and depressing commentary on the deteriorating quality of education methinks.   Hints: Don't get the mix too hot, humidity has a big effect, figure out which way the wind is blowing first, and don't inhale the smoke. Too much oxidizer will cause the steel case to rust or the mix to act like flash powder. Try not to Learn by Destroying your computah. <http://chemistry.about.com/od/chemistryhowtoguide/a/coloredsmoke.htm> <http://xtrem-experiments.com/pyro-compositions/colored-smoke.html>   -- 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

amdx <nojunk@knology.net>: Aug 10 08:59AM -0500 > The system is in a van. In the beginning wire 2 sizes larger than factory eg Hella wires seemed adequate then Liebermann suggested Powerstream for a kayak inverter. Once there I found the wire size calculator then Hella's point that a small voltage drop from 12V looses 30% of the light source.   > The alarm sirens and horn are powered now.   > Relays work with 8 and 10 Ga using the smaller wire for a signal.   If by signal you mean the wire that energizes the coil, it can be a lot smaller than 10ga. The coil may draw something like 120ma, so the wire diameter can be small.   There are two ways to power a relay. 1) You connect one side of the coil to ground and then switch +12V to the other side. 2) You connect one side of the coil to +12V then switch the other side to ground. A diode will allow current to flow if the voltage is higher on the anode than on the cathode. Current will not flow if the voltage is higher on the cathode than on the anode.   Has your original question been answered?   If you want an answer you need to ask one question and give enough details so we know what you are trying to do.   Mikek       --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com

N_Cook <diverse@tcp.co.uk>: Aug 10 10:12AM +0100 Hitachi CP X327, 3xLCD & discharge lamp, unusually the full component level sm is out there. As the lamp repeatedly strikes across giving short bursts of preliminary greenish light, the 5KV or so striking supply must work and also I assume some voltage from the main sustain, high power lamp ps, until the unit goes into protect mode. Initially I intend jury-rigging across (with added insulation) another known good lamp to see if a lamp problem. The lamp looks visibly fine, no cracks/crazes in the glass and no blacking in the active bulb area. Monitoring the mains supply current, usual surge for the low power ps coming on but only a hint of a surge for the high power ps coming on. I've previously had a projector where all that was wrong was the mains switch had arc-pitted contacts and could not supply the current for the lamp ps and so similar mains current symptom. I'll check that and check the internal cabling connectors, but what else to check, assuming it is a ps issue after the fudged lamp test also fails to light.

N_Cook <diverse@tcp.co.uk>: Aug 10 12:35PM +0100 Same weak green flashes on another bulb, so dig out the HV attenuator to see if there is 100V or so on the lamp supply at anytime, other than the 5KV trigger pulses

pedro <me@privacy.net>: Aug 03 07:16PM +0800 On Fri, 26 Jun 2015 10:46:48 -0700 (PDT), captainvideo462009@gmail.com wrote:   >On Friday, June 26, 2015 at 12:08:38 PM UTC-4, captainvi...@gmail.com wrote: >> I have a customer who wants to buy twelve 12.0 volt 8.0 AH gel cells from me. He uses these in his fire alarm panels and wants to keep a quantity in stock for when one of these panels goes down for battery failure. I've explained to him about the need for trickle charging these while they're sitting on the shelf, and rather than sell him 12 individual trickle chargers I was wondering if anyone knows of a cost effective series charger whereby I could put perhaps 6 in series and charge them all at the same time. I would probably not want to go above 6 and I would not do this with anything other than new batteries all of the same type and rating. Thanks, Lenny   >I was under the impression that parallel charging was not the way to go because it is difficult if not virtually impossible to equalize the current through each battery. Batteries having a lower terminal voltage would draw more current. The inverse would then be true with a higher terminal voltage. In series the entire string gets the same amount of current. Lenny   Lead-acid batteries charging is VOLTAGE-controlled, unlike NiXX. So parallel charging - well, floating actually - is what is required. Refer to the cell manufacturer for the appropriate voltage and do as Tom Miller suggested.

"Ian Field" <gangprobing.alien@ntlworld.com>: Aug 09 09:54PM +0100 "John-Del" <ohger1s@aol.com> wrote in message news:afefb606-0992-4a20-8a5e-11f3555add5e@googlegroups.com...   >> http://www.bbc.co.uk/news/entertainment-arts-33803144   >> Arfa :-(   > No one has mentioned his role as young Ebenezer in Scrooge 1951!   He was also in an episode of UFO.   A rather cheesy series about aliens who visit Earth and take people for organ harvesting.

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