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Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:14AM +1000 > up from behind the TV blinking his eyes while I asked him if the fuse > blew. He gave me trouble when I went out to the truck to get a new > module.   **LOL!           -- Trevor Wilson www.rageaudio.com.au

dansabrservices@yahoo.com: May 17 02:44PM -0700 I too have held onto items for way too long. In one case, I had the unit for almost 2 years. While moving others around, I realized this and ended up selling a few weeks later. Customer showed up the week after the sale looking for it... Threatened legal action. I told him, go ahead and see where that gets you. Never heard from him after that.   Dam

MJC <gravity@mjcoon.plus.com>: May 18 12:47AM +0100 In article <eo3sqhFid7jU2@mid.individual.net>, trevor@SPAMBLOCKrageaudio.com.au says... > > up from behind the TV blinking his eyes while I asked him if the fuse > > blew. He gave me trouble when I went out to the truck to get a new > > module.   That reminds me of a holiday job I had between school and college. The company made PA/music systems for supermarkets etc, designed by a very snooty engineer who deigned to look at prototypes. So he was inspecting one with the covers off quite closely when an electrolytic blew up, covering him with damp confetti. We had great difficulty not spluttering ourselves...   Mike.

rickman <gnuarm@gmail.com>: May 17 07:59PM -0400 On 5/16/2017 6:43 PM, Trevor Wilson wrote: > business with him. Ever.   > FWIW: I have retained repairs for as long as 2 years, waiting for > customers to collect their jobs.   That is the worst customer you've ever had? That doesn't sound so bad... Are you saying it bugged you that he was stupid enough to not examine the scratches himself? Otherwise this seems like a tame one.   --   Rick C

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 10:02AM +1000 On 18/05/2017 9:59 AM, rickman wrote:   >> FWIW: I have retained repairs for as long as 2 years, waiting for >> customers to collect their jobs.   > That is the worst customer you've ever had?   **No, not the worst. It's the one that sticks in my mind, because it was in the early days of my own business and, because I did not capitulate to his threats, I did not lose any money.     That doesn't sound so > bad... Are you saying it bugged you that he was stupid enough to not > examine the scratches himself? Otherwise this seems like a tame one.   **Nope. It was just one that sticks in my mind. After all these years, I kept the correspondence on file too.     -- Trevor Wilson www.rageaudio.com.au

etpm@whidbey.com: May 17 05:46PM -0700 On Wed, 17 May 2017 08:43:17 +1000, Trevor Wilson >business with him. Ever.   >FWIW: I have retained repairs for as long as 2 years, waiting for >customers to collect their jobs. I've been pretty lucky with customers. I only had to sue once. My business is machining but jerk customers come in all stripes. I live on an island that is mostly rural so it has that small town feel. You see folks when shopping and recognize them even if you don't know them personally. Anyway, I had a guy come into the shop with a welding job. He said his funds were limited and wondered if I could do the job for what he said he could afford. I said I couldn't but my son could and I would contact him. This is just good neighbor relations and it usually pays off. So I arranged for my son to do the job. Then for some reason my son couldn't do the job when it was promised so I went ahead and did the job. The customer came to pick up the job and I explained that I did the welding but would only charge him the lower price my son quoted. He then asks me if I'll take 40 dollars less. He had obviously planned to do this from the beginning. By this time I was so fed up with the whole thing I took his money and told him not to tell anyone how I had let him stiff me. For years after the incident every time I would see him in a grocery store or hardware store or wherever he would turn around and scuttle away. I hope the 40 bucks was worth avoiding me for several years. Eric

Taxed and Spent <nospamplease@nonospam.com>: May 17 07:07PM -0700 > would turn around and scuttle away. I hope the 40 bucks was worth > avoiding me for several years. > Eric   I would say it was!

bitrex <bitrex@de.lete.earthlink.net>: May 18 12:51AM -0400 On 05/17/2017 08:02 PM, Trevor Wilson wrote:     > **No, not the worst. It's the one that sticks in my mind, because it was > in the early days of my own business and, because I did not capitulate > to his threats, I did not lose any money.   You remember some dopey customer from when he was probably still playing the Saturday Night Fever soundtrack on that turntable and I was still being bottle-fed, and it wasn't even the worst?!

N_Cook <diverse@tcp.co.uk>: May 18 08:54AM +0100 On 16/05/2017 23:43, Trevor Wilson wrote: > business with him. Ever.   > FWIW: I have retained repairs for as long as 2 years, waiting for > customers to collect their jobs.   A large Roland Cube that bounced back about 6 times. Always the same reported problem of severe distortion on the lowest notes. The most difficult of repair jobs, finding a non-existent fault. Owner used this amp for his acoustic bass, as very light but could accomadate the double-bass notes. A serious case of RTFM. He was not interested in chorus,flange, amp types , just a basic amplifier , so except for volume and gain and tone he turned all the controls fully anticlockwise. That position on the mode? switch was octave bass.

Phil Allison <pallison49@gmail.com>: May 18 01:59AM -0700 Trevor Wilson wrote:   -------------------------   > The N. Cook thread got me to thinking about some of the worst customers > I've had in this business.   ** IME, the very worst customers are DJs.   First one I ever dealt with was a pommy called Dave.   He asked me to build him a "Musicolour" - a four channel music to light intensity device using triacs. These were available as kits from various suppliers after publication of the design in a hobby electronics magazine.   I assembled a kit and made a very professional job of it too, if I may say so.   After Dave had been using it for a couple of weeks he suddenly turned up in my workshop, the unit under his arm and **fuming with anger**.   He claimed I had tried to kill him, as the Musicolour had delivered him a terrifying electric shock from the case.   I took his claim very seriously as he was hovering over me and looked ready to biff me at any moment.   I first checked continuity from the ground pin of the 3 pin plug to the all metal case, it was good. I commented that he could not possibly have received a shock from the case - but Dave did not take this well, it made him madder.   Then I carefully quizzed him on the exact sequence of events:   Seems the unit was not operating so he decided to check the 10 amp supply fuse fitted in a cartridge holder on the back. It was then that he got the nasty shock.   The final revelation was the unit was plugged in at the time and Dave had one hand on the metal case while extracting the fuse with the other. He removed the screw off cap and then went for the fuse with his fingertips.   When I tried to explain that fuses should only be removed with the unit un-plugged he exploded at me saying he knew what he was doing and turned off the power with the front panel switch.   Oh dear........     .... Phil

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:37PM +1000 On 18/05/2017 6:59 PM, Phil Allison wrote: > unit un-plugged he exploded at me saying he knew what he was doing > and turned off the power with the front panel switch.   > Oh dear........   **Those old SATO fuse holders were death traps. But yeah, I get your point. People in the music industry can be, uh, unpredictable.     -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: May 18 04:22AM -0700 Trevor Wilson wrote:   --------------------   > > Oh dear........   > **Those old SATO fuse holders were death traps.   ** The events I described occurred in the mid 70s - finger safe fuse holders did not appear until much later.   Nanny state stuff - right ?     > But yeah, I get your > point. People in the music industry can be, uh, unpredictable.   ** DJs are *not* in the music industry.   DJs are just monkeys with turntables.   In fact, they have done a great deal to destroy the music industry.   Along with MP3s and TV shows like Rockwiz.       .... Phil

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:12AM +1000 > tone controls in the global feedback loop. Marantz ? In my book that > is no Marantz. Now a 2325, things of that vintage, now that's > Marantz.   **Well, in some ways. Big, heavy, big power transformer, nice to service, but not a great sounding amp and with some serious issues with the VI limiting system (I measured around 20 Watts, at limiting, when driving a pair of AR 10pi speakers). For me, the last, really good integrated amp from Marantz was the 1200b. Built in Chatsworth Cal. Stunning sounding amp. It was my first Marantz amp, when I started work at Marantz. The last receiver built in Chatsworth was the Model 18 (I think). I still have mine. Very interesting model. Sounds pretty good too. I also still have the mightiest Marantz of all - the Model 500 power amp. A big, beautiful, all hand built beast with phenomenal unreliability. When it works, it sounds fabulous.   As for your tone control thing, ALL Baxandall type tone controls (which is most of them) operate within a feedback loop. However, I suspect you mean within the power amp stage? If so, then you are thinking of 1980s vintage Luxman amps. ALL Marantz amps employed separate tone control circuits, with their own amplification and feedback systems.       -- Trevor Wilson www.rageaudio.com.au

jurb6006@gmail.com: May 17 09:05PM -0700 >"As for your tone control thing, ALL Baxandall type tone controls (which is most of them) operate within a feedback loop. However, I suspect you mean within the power amp stage? If so, then you are thinking of 1980s vintage Luxman amps. ALL Marantz amps employed separate tone control circuits, with their own amplification and feedback systems. "   Yes I meant in the power amp stage. And I swear I saw a Marantz that was like that, in fact I probably got the print on the PC but I have alot of Marantz prints. I was actually surprised to see it, and it was the only one. I remember it was a lower end model but it still had the Marantz look.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:39PM +1000 > alot of Marantz prints. I was actually surprised to see it, and it > was the only one. I remember it was a lower end model but it still > had the Marantz look.   **I could be wrong, but I doubt it. Luxman, absolutely. Quite a few of theirs employed such a system. If you figure out which Marantz, let me know. I have pretty much every service manual for every model.       -- Trevor Wilson www.rageaudio.com.au

"pfjw@aol.com" <pfjw@aol.com>: May 17 10:00AM -0700 > That's just wrong. If reforming by running a complete set from a variac, wind the voltage up _very_ slowly until rectifier conduction just begins. At this point the rect won't pass much current, and any bad cap present will conduct, keeping the voltage on the lytics low. After a while the variac can be inched up _slightly._ Bear in mind that even a 2v increase on 240v mains increases rectifier conduction many times 1%, so very slowly does it.   > It's not the ideal method but it does work.   > NT   The thing about rectifiers is that they are go/no-go devices. The thing about Variacs is that they are not current-limiting devices but voltage limiting devices.   Which means: When the rectifier "goes" the voltage that hits the caps is a function of the voltage from the transformer secondary to the transformer primary. In a Transformer-type radio. Or the minimum trigger voltage for the rectifier on an AA5 type.   The typical tube rectifier will operate somewhere between 75% to 80% of the rated filament voltage. In some few cases, as low as 70%.   The typical tube rectifier as in those devices under discussion operates at a filament votage of 5V for transformer-types and 50V for an AA5-type set.   B+ for the typical transformer-type set is about 350 VDC. About 100 VAC for an AA5. Caps are rated (usually) at 450V and 150V respectively. "Typical", not "EVERY".   Meaning that 245V is what the caps will see in the one case, and 70V for the other.   Again, not hardly a soft start. Nor worth bothering about. Replace the poor, silly things outright and be done with it.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: May 17 04:23PM -0700 On Wednesday, 17 May 2017 18:00:39 UTC+1, pf...@aol.com wrote: NT:   > > That's just wrong. If reforming by running a complete set from a variac, wind the voltage up _very_ slowly until rectifier conduction just begins. At this point the rect won't pass much current, and any bad cap present will conduct, keeping the voltage on the lytics low. After a while the variac can be inched up _slightly._ Bear in mind that even a 2v increase on 240v mains increases rectifier conduction many times 1%, so very slowly does it.   > > It's not the ideal method but it does work.   > The thing about rectifiers is that they are go/no-go devices.   wrong. bzzt. As folks familiar with valves know that they will pass only small current when the heater is run well below rated voltage.     NT

"pfjw@aol.com" <pfjw@aol.com>: May 17 07:49PM -0700 > As folks familiar with valves know that they will pass only small current when the heater is run well below rated voltage.   a) Why is it that so many mistake *voltage* for *current*? b) Please explain to me how a Variac delivering 84 VAC on a transformer-type device, and that being the minimum trigger voltage on say... a 5Y3, will deliver any less current than that rectifier is able to pass at that voltage? c) Further, explain to me how 245 VDC constitutes any sort of soft-start for the on-board capacitors.   If one happens to have a metered Variac, one can observe the onset of B+. It does NOT hover when the rectifier starts to pass DC.   Peter Wieck Melrose Park, PA

"Ian Field" <gangprobing.alien1@virginmedia.com>: May 17 08:34PM +0100 <pfjw@aol.com> wrote in message news:605c7eab-c468-46cc-88d9-44ddf8c43aa9@googlegroups.com... > For critical and highly 'designed' applications, film caps are the only > way to fly. For things that are less critical, an electrolytic might do > just fine.   Allegedly; there's something about contact potentials with electrolytics.   If its real - there wouldn't be much mystery about it causing distortion.

"pfjw@aol.com" <pfjw@aol.com>: May 17 12:55PM -0700 > yes. OTOH they're inside a closed cabinet.     Just a basic, but relevant point - Dynaco cabinets of that vintage are not sealed.   And, yes, when speakers rely on mechanical vs. soldered connections, they become weak points. AR (et.al.) pots. Dynaco rotary switches. Internal banana connections (yes, they exist). And more.   As a hobbyist with a 40+ year immersion in the hobby, and in a region where all sorts of things are thick on the ground and having lived within 100 miles of a dozen major audio manufacturers, I have seen *lots* of strange stuff. Most recently (May 12th), a Dynaco ST70 and a pair of MkIIIs marked by, and from a Hammond organ. Go figure.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: May 17 04:25PM -0700 > As a hobbyist with a 40+ year immersion in the hobby, and in a region where all sorts of things are thick on the ground and having lived within 100 miles of a dozen major audio manufacturers, I have seen *lots* of strange stuff. Most recently (May 12th), a Dynaco ST70 and a pair of MkIIIs marked by, and from a Hammond organ. Go figure.   > Peter Wieck > Melrose Park, PA   Hmm, I thought of crimps as pretty reliable.     NT

Ralph Mowery <rmowery28146@earthlink.net>: May 17 07:49PM -0400 In article <9468542c-342a-45eb-9641-8fc5a755bc5a@googlegroups.com>, tabbypurr@gmail.com says... > > Melrose Park, PA   > Hmm, I thought of crimps as pretty reliable.   > NT   Crimps are very good when done correctly. I think what the OP is referring to is speakers connected with things like the push on connectors and phono plugs. Not realaly a good hard mashed together type of connector,but one that slides off and on.

Jon Elson <jmelson@wustl.edu>: May 17 02:03PM -0500 > What is all this nuff and puff stuff? These newfangled condensors should > be marked with cm. Bring back pith balls.   > NT a pF is 1 millionth of a uF. A nf is 1 thousandth of a uF. So, .001 uF is 1 nF. 1000 nF is 1 uF.   Jon

rickman <gnuarm@gmail.com>: May 17 03:22PM -0400 > complicated and for no advantage. Kind of reminds me of trying to > determine if I need a 1/2" or a 12 mm socket, when both look to be the > same size.... More senseless complication....   I'm surprised you are using pF, I would have thought you'd be using uuF.   http://bfy.tw/1vkq   --   Rick C

"pfjw@aol.com" <pfjw@aol.com>: May 17 10:07AM -0700 On Wednesday, May 17, 2017 at 11:51:04 AM UTC-4, N_Cook wrote:   > I don't know what this plate may be, can you Dremmel+.5mm grinding disc, > separate it from the switch and then desoldering?   Dremel Grinding Disc PC Boards Thousands of tiny bits of metal   Does anyone else see a recipe for disaster here?   I keep one of these - which, despite its size, is very good at fine cuts, almost to the 'nibbling' level. And no swarf. Sharp, tough, cuts mild steel very easily.   https://www.channellock.com/data/default/images/catalog/original/E338-842_1-842.png   Peter Wieck Melrose Park, PA

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