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"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 05 12:06AM "N_Cook" wrote in message news:nb103f$s5i$1@dont-email.me...   On 29/02/2016 06:39, Ken Layton wrote: > years ago and still carries the "PRB Line":   > http://www.russellind.com/prbline/index.html   > They should have your belts. Just give them a call.   But do they say whether they are new belts or old stock (so half perished already)? The total absence of any supplier stating they had new belts made me move over to cutting my own belts , flat and square , from silicone rubber kitchen products, no returns yet from broken examples.           Can you remind us what these products are?   I remember some conical shaped thing, and I think this is actually quite a good idea.       Cheers,   Gareth.

N_Cook <diverse@tcp.co.uk>: Mar 05 08:35AM On 05/03/2016 00:06, Gareth Magennis wrote: > a good idea.   > Cheers,   > Gareth.   The main one is collapsible silicone funnels, ridiculous idea I know so I grapped 12 or so before the importers would come to their senses, 6 black and 6 dull red unlike the usual "neon" kitchen silicone . You also need some razor blades set up in a holder to split the thickness and some mandrels to stretch over, to then cut around in a sort of lathe fashion, then making finishing cuts by eye and hand , because the rubber always moves a bit in the cutting process, so end of cut will never exactly meet the start. Luckily I've never come across a situation where you need a fair face on both sides of a band, even then perhaps a 180 deg axial twist in such a band, and back on the other side, could work there. For walkman size bands, I set up a sort of grinding machine with "Dremmel" and "diamond" disc to "grind" back imperfections of such cut bands.

DaveC <not@home.cow>: Feb 28 09:14PM -0800 for refurbishing a tape deck, I need some belts. I googled a few places but nothing very inspiring (not a great selection).     Anybody have a source they like and use?   (If you're just going to Google, don't bother, I've already done that…)   Thanks!

N_Cook <diverse@tcp.co.uk>: Feb 29 06:41PM On 29/02/2016 17:51, Cydrome Leader wrote:   > I've always wondered about the freshness factor of their stuff these days. > They must be selling dozens of belts a month these days.   If I ran a company supplying rubber drive belts, I'd make great play in my blurb, that they are new cut/moulded stock. As none of the companies I've found selling belts for legacy equipment say this, I assume they only have old stock , next to useless stock.

Cursitor Doom <curd@notformail.com>: Feb 28 03:28PM On Sun, 28 Feb 2016 15:33:02 +0100, Dimitrij Klingbeil wrote:   > I mean, you posted at the very beginning (long before finding the slow > diode) that you've found and replaced some obviously defective parts, > but I can't remember if you ever posted, exactly which ones they were.   I think you may possibly be getting mixed up with a different repair here, Dimitrij. I do have some flaky capacitors to replace when I return and I'll note which ones I change for your information. As for what previous technicians may have done, I have no idea what if anything has been replaced - apart from that one obvious diode. I got absolutely no background information on this scope, it was given to me for nothing by some guy who was emigrating so its past will now always remain a mystery. It's a pity, because this obviously adds another set of unknowns into troubleshooting the thing, but it's just something I'll have to live with I guess. In all honesty, this repair is proving to be a 'baptism of fire' for me in the world of SMPSs of which I admit I know very little (yet a lot more than I did 3 months ago!) :)

Dimitrij Klingbeil <nospam@no-address.com>: Feb 28 07:06PM +0100 On 28.02.2016 16:18, Cursitor Doom wrote: > of noise across that resistor but that was before I was informed of > the importance of hooking the supply up to a load, so the test was > probably invalid.   Also, even with a dummy load connected, the stray capacitance of an oscilloscope, when hanging off the loose end of a power circuit with some 800 to 900 V worth of HF on it, would probably cause so much undue capacitive loading that the power supply circuitry would hardly handle it. That may have been the reason why you just got noise (the overload from the hanging scope may have affected the over-current shutdown of the power supply controller). As I said, the proper way would be with an isolated high voltage differential probe (such a probe would present very little stray parasitics) or maybe with a well matched pair of (identically compensated) HV probes in subtract mode.   Dimitrij

Dimitrij Klingbeil <nospam@no-address.com>: Feb 28 07:23PM +0100 On 28.02.2016 19:06, Dimitrij Klingbeil wrote: > some 800 to 900 V worth of HF on it, would probably cause so much > undue capacitive loading that the power supply circuitry would hardly > handle it.   P.S. That voltage estimate has probably surprised you. Unless one looks at the circuit schematic and adds all the voltages from all the storage elements (inductors / capacitors), considering timing and phase, it may not be obvious that the thing was intended to run at such high voltage levels. But there's a reason why they used a 1500 V transistor in it.

Cursitor Doom <curd@notformail.com>: Feb 28 11:35PM On Sun, 28 Feb 2016 14:02:33 -0800, jurb6006 wrote:   [...] > I consider a dim bulb tester a must for this type of work.   Ah, that makes much more sense now; many thanks for that clarification.

DaveC <not@home.cow>: Feb 28 02:11PM -0800 Sony TC-WR99ES (or any TC-WR series cassette tape deck).     I can find for-pay manuals. Are there any resources for free downloads? (tried eserviceinfo.com)   Thanks.

DaveC <not@home.cow>: Feb 28 02:24PM -0800 Found it on electrotanya.com   -=-=-=-

Mike Tomlinson <mike@jasper.org.uk>: Feb 27 06:56PM >On mine, the frame also extends back towards the intake to >hold the fan motor and make a venturi/shroud for the fan blade.   Yes, same here. It's all one piece. The section holding the ceramic element is square, then there's a short cylinder to the fan housing which is square. The lot fixes to the back half of the enclosure with 4 screws.   I suspect this is pretty much a commodity part made in China and badged with OEM logos as required.   I've ordered the 95C switch, pretty sure that'll do the trick. Thanks again for your help, have a virtual pint on me :)   -- (\_/) (='.'=) Bunny says: Windows 10? Nein danke! (")_(")

mroberds@att.net: Feb 27 05:56PM > En el artículo <naqubs$uaf$1@dont-email.me>, mroberds@att.net escribió:   >> Taking mine apart,   > You didn't have to go to that much trouble, but thank you.   I use it a lot in fan-only mode, so it was about ready for its annual dusting anyway. :)   > There's 4 ceramic cores with two heat levels selected by a switch > (heat level 1 = 2 cores operating, heat level 2 = 4 cores operating)   Same here.   >> The part I have looks like their "AUT-P" series (with the white >> plastic tab)   > That sounds like a resettable one.   It is. There is no user-resettable button; you just have to unplug the heater and let it cool off.   > The ceramic element is held in place in a hard plastic frame, so isn't > going to be allowed to get very hot.   Same here. On mine, the frame also extends back towards the intake to hold the fan motor and make a venturi/shroud for the fan blade.   Matt Roberds

N_Cook <diverse@tcp.co.uk>: Feb 28 11:26AM In hindsight it should have been obvious why no lead mode. There is an error on the Mesa schematic of Mesa Boogie 3 on Elektrotanya. The lead-switch should take the common LDR1 - 4 line, to ground and not directly shorting those 4 leds as in the diagram, doh!

andrew@cucumber.demon.co.uk (Andrew Gabriel): Feb 27 11:20AM In article <sNGdnTReYdJz31fLnZ2dnUU7-I-dnZ2d@westnet.com.au>,   > I'll believe Aluminium or steel I must admit to only a little actual > experience. > Some Cable guy should give an actual answer.   Ordinary soldering can be used with iron - soldering iron bits are often copper core for thermal capacity and conduction, with iron plating which wets well with solder but doesn't oxidise/corrode as quickly as a bare copper bit does.   As you go to steel and then stainless steal, it gets harder to do. Stainless steal in particular is protected from corrosion by a very tough layer of chromium oxide (I don't know if it's possible to solder stainless steel at all).   Aluminium has a similar problem - a very tough layer of aluminum oxide which needs a suitable flux to strip through. However, it also needs a different solder alloy to wet it - it's a long time since I did it but ISTR using a solder alloy containing silver.   A secondary problem with soldering dissimilar metals is that any moisture risks causing galvantic action/corrosion of the join, and in the case of aluminium, this happens even between the aluminium and the solder used. Selecting a flux which can strip the aluminimum oxide well whilst not leaving any residue which eventually corrodes the join is a bit of a challenge.   -- Andrew Gabriel [email address is not usable -- followup in the newsgroup]

DecadentLinuxUserNumeroUno <DLU1@DecadentLinuxUser.org>: Feb 27 01:10PM On Sat, 27 Feb 2016 11:20:43 +0000, Andrew Gabriel wrote:   > As you go to steel and then stainless steal   Engineering schlip?

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 04 08:07PM Hmm, this might be a problem.   Have come across a couple of cases now where a cheap jack plug has become stuck in a Neutrik combi socket.   http://www.neutrik.com/en/xlr/combo-i-series/     It looks like the cheap jack plug tips are not quite as rounded as usual. This means that they get stuck fast in the Combi, though they work just fine in other jack sockets.     If you force them out, the tip of the jack will just not get past the connector, but instead will just take it with it and destroy it, or the jack tip becomes separated from it's body and is left embedded in the Combi.     Not good.           Gareth.

N_Cook <diverse@tcp.co.uk>: Mar 05 08:24AM On 04/03/2016 20:07, Gareth Magennis wrote:   Or is it like the more common problem of tips , 2.5/3.5mm jacks stuck in headphone sockets, due to lack of strong metal these days in the neck part, preceeding the tip, to resist normal contact forces?

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 05 11:07AM "N_Cook" wrote in message news:nbe4u5$5qu$1@dont-email.me...   On 04/03/2016 20:07, Gareth Magennis wrote:   Or is it like the more common problem of tips , 2.5/3.5mm jacks stuck in headphone sockets, due to lack of strong metal these days in the neck part, preceeding the tip, to resist normal contact forces?           No, I have first hand experience of putting more than one of these cheap jacks into more than one Neutrik Combi and them getting stuck, after removing 3 that had got stuck via a customer.   On another occasion a Focusrite pre-amp had a tip stuck in the socket. There is a small hole in the back of the Combi where you can insert a tool to push out the jack, but there was no way it was going to budge without damage.         Gareth.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Mar 04 03:54PM -0800 > ...the diode *was* in backwards... If you had positive bias on the control grids, you may have damaged the output tubes. Some of the cathode coating could have evaporated and gotten deposited onto the grids, leading to grid emission.

Phil Allison <pallison49@gmail.com>: Mar 04 07:24PM -0800 > As they age, a pronounced *60* cycle hum begins > that appears to be volume dependent - that is, > the hum goes down as volume increases.   ** The electros are leaking badly as they heat up - cos they are being over-voltaged. Even 10mA ( about 1W ) would get them damn hot.   So the negative bias voltage applied to the output tube grids has a high level of 60Hz ripple. If the 6550s were perfectly matched, this would not matter - but they aren't so some of this voltage get amplified.   I don't buy your story of the 1N4004 diode being reversed, 6550s draw over 500mA each with positive grid bias and the amp would have quickly blown up if that were the case.     ... Phil

captainvideo462009@gmail.com: Mar 04 01:43PM -0800 My son's dog ripped an AV cable out of his TV leaving the video and two audio RCA connectors broken off in the set. I looked at it and it does not seem feasible to try to remove them. Although that was the last A/V input, he has an abundance of unused HDMI inputs. Is there an adapter that will convert a base band input to an HDMI output? With base band going in I wouldn't expect a high definition picture coming out, but just 480 resolution along with standard analog sound would be fine to utilize one of his other unused HDMI inputs on the TV. Thanks, Lenny

"jfeng@my-deja.com" <jfeng@my-deja.com>: Mar 04 06:30PM -0800 > 480 resolution along with standard analog sound would be fine to utilize > one of his other unused HDMI inputs on the TV. Thanks, > Lenny Do a "rgb hdmi" search on eBay.

Chuck <ch@dejanews.net>: Mar 04 08:37PM -0600 On Fri, 4 Mar 2016 13:43:33 -0800 (PST), captainvideo462009@gmail.com wrote:   >in I wouldn't expect a high definition picture coming out, but just >480 resolution along with standard analog sound would be fine to utilize one of his other unused HDMI inputs on the TV. Thanks, >Lenny     Lenny,   Here you go. http://www.monoprice.com/product?p_id=9994 Chuck   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Cursitor Doom <curd@notformail.com>: Mar 05 12:05AM On Thu, 03 Mar 2016 16:41:53 -0600, Chuck wrote:   > It was rumored that the glue was made by Sony and that they sold it to > other manufacturers but didn't use it themselves until many years > later. T   Sony, yes it was them; I remember now. The goo was suspicious as it was commonly used on high impedance areas of the boards of multiple manufacturers where there was no ostensible need for it.

Phil Allison <pallison49@gmail.com>: Mar 04 04:31PM -0800 > How could so many manufacturers make the same mistake all at the > same time? And most of them were the old-line Boston Sound makers > - Advent, AR, EPI, KLH and more who should really have known better.   ** You can add Bose and JBL to that list.   First time I saw crumbling surrounds was on a pair of JBL LE8Ts sold in 1970 - lasted less than 5 years. The local ( Australian) JBL agents replaced the cones at no cost when the owner complained bitterly about it.   Interestingly, the use of foam surrounds was taken up by nearly all makers in the USA but few elsewhere. In the Europe and the UK, rubber roll surrounds were the norm: eg KEF, Celestion, Philips, Seas and Wharfedale woofers.   Neoprene rubber has a indefinite life and many such woofers from the 70s are still working today.     .... Phil

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