- TIP: avoiding dried up/blocked ink-jet carts - 18 Updates
| tabbypurr@gmail.com: Apr 24 09:51AM -0700 On Tuesday, 24 April 2018 15:23:15 UTC+1, jurb...@gmail.com wrote: NT: > >"Oh, yes there is an exception. If an old microwave has no turntable, forget it, those ones are hopeless and a food poisoning risk. " > The turntable is actually a cheap way out of real engineering. it's sound engineering > Microwaves without them "stir" the waves with a reflector at the top which is motor driven, usually off the fan and some of them just use the air flow to blow them into turning. yes, with abysmally uneven cooking as the result. > Now if you have a microwave with both, there's a good one and I believe yes, those are best for cooking evenness. Of course it still doesn't counter the tendency for things to be boiling on the outside & ice in the centre. NT |
| tabbypurr@gmail.com: Apr 24 09:55AM -0700 > >"But the newest one knows the difference between three different kinds of popcorn, knows how to actually 'bake' a potato, or even three of them, and will also defrost without parboiling." > I can do that by using it right. I can also adjust the car seats and mirrors myself, turn the courtesy lights on and off myself. I'm just a dinosaur I guess, probably a great feature for the truly stupid, and certainly there are such folk. To me all that is just junk, bad design. NT |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Apr 24 11:32AM -0700 To which I add the differences between the average tube-based Euro radio made between say.... 1950 and 1980, and the average American tube radio of the same era. Euro radio: a) Never use one part when four-or-more would do. b) Let's make the controls very, very fussy, with lots of moving parts. c) Let's make the chassis an integral part of the cabinet (case) including wires, springs, tuning mechanisms and speakers. d) Let's make services as simple as changing a dial lamp the work of several hours. e) And after all that, let's make just about every radio look the same, but make very sure that there are no interchangeable parts but-for the tubes - and not all of those. American Radio: a) Five (5) tubes, exceptionally, sometimes six (6). b) If we can make one part do five things, go for it! c) Who needs a power-transformer? d) Let's let the industrial designers go nuts. Colors? Sure. Shapes? Whatever can be molded. e) Let's all make all our radios from a palette of perhaps two dozen interchangeable parts in all, including tubes. And so it goes. Our oldest microwave, now 12 years old, is a GE countertop that sits on our third floor and is used by a couple of seminary students we are sponsoring. Every day. They keep it sort-of-clean such that I have to power-wash it maybe twice a year. I remember paying $50 for it as a direct-purchase from GE as part of their bulk-buyer program. Our newest is an over-stove Frigidaire at the summer house, at about 6 years, used during the summers only, and then only lightly. Does the trick and as a vent-hood and stove light is not at all bad. More features than we would normally get, but we purchased it as a 'remainder' from a general contractor at the end of a large project. NIB, but it had sat on the site for two years. No issues, and at $75, a bargain. The middle one is, at 8 years, the most feature-laden, a Panasonic countertop model that knows the difference between one and three Idaho potatoes when asked to bake them, and between 'regular', 'diet' and 'jumbo' popcorn packages, without being told. At 1,200 watts, it will cook. The point is not that it has these features, but that having the features is a way of accident avoidance. Sure, I know how many minutes each type of popcorn should take, but by hitting a single button, the chances of mis-entry are reduced. And so forth. A poor workman blames his tools, but a good one picks the right tool for the job and relies upon it. Peter Wieck Melrose Park, PA |
| Chuck <ch@dejanews.net>: Apr 24 02:53PM -0500 On Tue, 24 Apr 2018 09:10:59 -0700 (PDT), "pfjw@aol.com" >I keep 3a, 4ax, 28, M5 and Athenas from AR. As well as a pair of TSW-110s at the summer house. >Peter Wieck >Melrose Park, PA I heard somewhere recently that Jim Winey is not doing so well. Love his speakers and since i just moved back to MN., I hope to visit the factory again in the near future. |
| jurb6006@gmail.com: Apr 24 01:45PM -0700 >"Magnepan. Great Bear Lake, MN" Friend of mine had a p[air of MG-1 (I think A) and they were pretty damn good. He sold them mainly due to size and the fact that he could make money on them, he got them for $ 100. The guy he bought them from said they rattled at high volume, we figured we would have to work on them, I looked it up, there are things to glue etc. on them. But we took them up to about 100 WPC with alot bass and they were fine at that level, and the seller had guess what - bigger pair of Maggies. In his room they actually sounded better backwards. (Boseapans ? lol) Don't know where the highs were coming from but they came, it the HF driver also bipolar ? I would guess so. Speaking of planars, I would like to at least hear a pair of Quad ESL-63s. There's something I might buy if I hit tho lotto, not a new car for sure. But I don't play because it is a sucker bet. I had some ideas for electrostatic speakers, could have worked but I found out it had been tried. I guess it wasn't worth the trouble sonically. I was going to take some 6MJ6sw or other horizontal output tubes and run them stacked and bridged to eliminate all the transformers, making it DC coupled. I think I would have had to run them stacked in series (like an Ampzilla) to get the required voltage. not a cheap undertaking but neither are ESLs in the first place. Ever see the schematic for the ESL-63s ? Thing has a delay line with several taps. It is said that the sound is like it is coming from behind the speaker, that's probably why. Some say those Maggies lack bass. I found them not to be "heavy" by any stretch, bit not really lacking. For my use I would have used subwoofers with them, but I am a bass freak. |
| jurb6006@gmail.com: Apr 24 01:55PM -0700 >>"them into turning. >yes, with abysmally uneven cooking as the result. " Some of them weren't all that bad. Chernobyl wasn't bad, and the one at the shop wasn't bad, but then those were not $ 59 specials either. They were BIG. >"Of course it still doesn't counter the tendency for things to be boiling on the outside & ice in the centre. " Yup, people think they cook from the inside out but that is an old Husband's tale. They heat the water in the food. And there are no power levels, the supposed power levels are just duty cycle turning the magnetron on and off. (I wonder if it accelerates cathode stripping) I only saw one microwave with 2 actual power levels and it was ancient. It actually had an extra tap on the primary of the power transformer to cut the voltage. I don't remember but I assume it would have to have a separate filament transformer, but back when they were willing to put more than ten bucks into a $ 300 item we got things like that. |
| jurb6006@gmail.com: Apr 24 02:05PM -0700 >"probably a great feature for the truly stupid, and certainly there are such folk. " I used to wonder what went through some people's mind, but I wonder no more. NOTHING goes through their mind. I used to flip some cars for extra money. (back when there was such a thing as extra money) So I have this shitcan on the paper. Little Dodge Omni had needed a clutch. The ad said "4-cylinder, 4 door, 4 speed, $ 400. People cal and ask "Do it have a cassette ?". No, it has a 400 disc changer and a 2,000 watt competition stereo system with bluetooth which hasn't even been invented yet, when would you like to come and test drive it ? Friend of mine sells a car. Guy calls a few hours later and says "Hey, this car don't run", "Is there gas in it ?". Click. What happened to the median percentiles ? People either qualify for MENSA or a Darwin award and not much common sense in between. |
| jurb6006@gmail.com: Apr 24 02:12PM -0700 >"To which I add the differences between the average tube-based Euro radio made between say.... 1950 and 1980, and the average American tube radio of the same era. " But Euro is the bomb ! Look at new cars, want an aftermarket radio ? In the old days it was two nuts in front and a bolt in the back, now you have to cut the HVAC controls off of it, get a kit from Crutchfield and be handy enough to build the damn thing. |
| Terry Schwartz <tschw10117@aol.com>: Apr 24 02:32PM -0700 White Bear Lake. About a long stone's throw from me. I grew up spending my summers on that lake. |
| tabbypurr@gmail.com: Apr 24 08:09PM -0700 > c) Who needs a power-transformer? > d) Let's let the industrial designers go nuts. Colors? Sure. Shapes? Whatever can be molded. > e) Let's all make all our radios from a palette of perhaps two dozen interchangeable parts in all, including tubes. your lists don't represent the euro valve radios I've worked on by any means > A poor workman blames his tools, but a good one picks the right tool for the job and relies upon it. > Peter Wieck > Melrose Park, PA and doesn't buy the tool with a great big pile of gimmick features NT |
| tabbypurr@gmail.com: Apr 24 08:17PM -0700 > I had some ideas for electrostatic speakers, could have worked but I found out it had been tried. I guess it wasn't worth the trouble sonically. I was going to take some 6MJ6sw or other horizontal output tubes and run them stacked and bridged to eliminate all the transformers, making it DC coupled. I think I would have had to run them stacked in series (like an Ampzilla) to get the required voltage. not a cheap undertaking but neither are ESLs in the first place. > Ever see the schematic for the ESL-63s ? Thing has a delay line with several taps. It is said that the sound is like it is coming from behind the speaker, that's probably why. > Some say those Maggies lack bass. I found them not to be "heavy" by any stretch, bit not really lacking. For my use I would have used subwoofers with them, but I am a bass freak. ESL57s are pretty awesome, though I wouldn't say they look good. Would you really need to stack LOP tubes? Static speakers can be quite simple, they used to get used driven directly IIRC as tweeters in some stuff. The delay is necessary in the Quads so the treble is a bit more point sourced, and you don't get the outer edges cancelling the sound produced by the centre as the latter passes by the former. NT |
| tabbypurr@gmail.com: Apr 24 08:19PM -0700 > >"Of course it still doesn't counter the tendency for things to be boiling on the outside & ice in the centre. " > Yup, people think they cook from the inside out but that is an old Husband's tale. They heat the water in the food. > And there are no power levels, the supposed power levels are just duty cycle turning the magnetron on and off. (I wonder if it accelerates cathode stripping) I only saw one microwave with 2 actual power levels and it was ancient. It actually had an extra tap on the primary of the power transformer to cut the voltage. I don't remember but I assume it would have to have a separate filament transformer, but back when they were willing to put more than ten bucks into a $ 300 item we got things like that. The most common way to do reduced power in the early 70s was with an HV cap & HV switch. If you're going to cook a mousse that's the sort you want. You could reduce both filament & anode (or cathode really), that would work. It's how they used to run bright emitters in the 20s. NT |
| jurb6006@gmail.com: Apr 24 11:58PM -0700 >"Would you really need to stack LOP tubes? " I think the max plate voltage of a 6MJ6 is about 5 KV, so it wouldn't quite do it, even bridged, I think. >"The most common way to do reduced power in the early 70s was with an HV cap & HV switch." You mean like a lower value cap for the lower power level ? >"It's how they used to run bright emitters in the 20s. " What is a "bright emitter" ? |
| tabbypurr@gmail.com: Apr 25 03:02AM -0700 On Wednesday, 25 April 2018 07:58:34 UTC+1, jurb...@gmail.com wrote: NT: > >"Would you really need to stack LOP tubes? " > I think the max plate voltage of a 6MJ6 is about 5 KV, so it wouldn't quite do it, even bridged, I think. Picking the first random ES design I see 475v dc bias. > >"The most common way to do reduced power in the early 70s was with an HV cap & HV switch." > You mean like a lower value cap for the lower power level ? 2nd smaller cap in series with the ac HV feed, shorted for full power. > >"It's how they used to run bright emitters in the 20s. " > What is a "bright emitter" ? before dull valve emitters were discovered, valves/tubes used thoriated tungsten direct heated bright emitters. They ran white hot. Nuke magnetrons use thoriated tungsten bright emitters. NT |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Apr 25 04:40AM -0700 > before dull valve emitters were discovered, valves/tubes used thoriated tungsten direct heated bright emitters. They ran white hot. Nuke magnetrons use thoriated tungsten bright emitters. These must go back to pre-DeForest days?? I have some direct-heat thorated tungsten 00, 01 and 71A tubes, as well as a number of UV99s and similar. Not a one of them gets much past a mild orange. Not to mention 2A3, 10 and 50s. The closest thing to a "hot" tube I have is a 10, and that filament is about like a 25 watt tube running at 50V or so. Which tubes are these? Peter Wieck Melrose Park, PA |
| John-Del <ohger1s@gmail.com>: Apr 25 04:52AM -0700 > your lists don't represent the euro valve radios I've worked on by any means > NT I have to agree with Peter, but maybe it's just that the only German radios we saw imported were the high end models. Really, the AA5 was so simple, reliable, and performed so well that imports really couldn't compare in a consumer driven market. When I was an early teen, I was given all the tube radios to work on at the family shop, and I always hated the Grundigs, Emuds, Blaupunkts, etc. because they were a pain in the ass to work on as opposed to the AA5(6) or FM versions of the same. I remember spending a whole afternoon changing out the piano key switch assy on several. Hated them. They performed well and sounded fabulous, but that didn't concern the guy on the bench. The good news was that Sams rewrote the schematics to put them in the familiar layout that we were used to on this side of the Atlantic, so that helped. |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Apr 25 06:40AM -0700 > I have some direct-heat thorated tungsten 00, 01 and 71A tubes, as well as a number of UV99s and similar. Not a one of them gets much past a mild orange. > Not to mention 2A3, 10 and 50s. The closest thing to a "hot" tube I have is a 10, and that filament is about like a 25 watt tube running at 50V or so. > Which tubes are these? On further research: The cathode of a magnetron provides the electrons through which the mechanism of energy transfer is accomplished. The cathode is located in the center of the anode and is made up of a hollow cylinder of emissive material (mostly Barium Oxide) surrounding a heater. The feeding wires of the filament must center the whole cathode. Any eccentricity between anode and cathode can cause serious internal arcing or malfunction. Does not seem to be much Thorium involved?? |
| jurb6006@gmail.com: Apr 25 09:21AM -0700 >"Picking the first random ES design I see 475v dc bias. " According to RCA's RC30 the peak pulse plate voltage it rated 5,000 volts. Without reading all the details this is of course with negative voltage on G1, it is the retrace pulse for the yoke and rectified for HV. So a pair stacked SESAPP would yield 2,000 volts peak at best. Bridged, of course 5,000 volts. I'm fairly sure most ESLs need more than that. Without going to transmitter tubes I think that is about the highest voltage to be had except in a HV shub regulator such as a 6BK4. Those are good for 27,000 volts but at 5,000 volts will only pass 750 uA. I think that only works out to about 16 watts. Unless ESLs lose a ton of power in the internal transformer that will not do. The book doesn't give plate dissipation but the tube s designed with the anode away from the glass and they do get red hot and work just fine. It is not impossible though, first of all with that topology, triodes should be easier to deal with. It would be a matter of a bunch of them in parallel which would cost more, but a true audiophile doesn't care. It doesn't give the maximum heater cathode voltage but I am assuming any design will need separate floating filament supplies. Not too hard with modern SMPS technology. However there is also the issue of frequency response. Since it is designed for HV shunt regulator use I imagine its frequency response is not stellar. I'm not sure now much can be done with feedback when there is that much open loop voltage gain. Plus the capacitive load doesn't help. >"2nd smaller cap in series with the ac HV feed, shorted for full power. " Makes sense. I red that the power id chiefly determined by the cap value, the transformers are not all that different, except the one I mentioned that actually had an extra tap for lower power. In light of that, when I replace the cap in this 1992 Litton, what about using a higher value to squeeze a few more watts out of it ? Is that too dangerous or otherwise not feasible ? To me, it is damn hard to have too much power, you just use less time, and since this doesn't ave real power control as far as I know, it just cycles anyway. Of course it might already have the biggest value on practice because it is a fairly large unit and I remember it had alot of power when it was new. We had to get used to it, it wasn't like the elcheapos. I would up the cp value for decent results but if it is going to burn something up because of it I'll leave it as designed. >"Nuke magnetrons use thoriated tungsten bright emitters. " AHA, so that filament is already burning pretty hot then right ? I see. |
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