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oldschool@tubes.com: Mar 01 06:33AM -0600 On Tue, 28 Feb 2017 17:17:21 -0500, Ralph Mowery >got here.   >The taxes and whatever are in the price you see on Ebay. You will not >be charged mpore at a later date.   Ok, I wont worry anymore now..... I just read that legal disclaimer and got all worried....   >2 or less. To get a 1 st class letter out of the US to another country >costs about $ 1.25. China does pick up the out going postage form what >I have heard.   The shipping on this item was $1.50. I cant imagine how they can ship it for so little money, but they must be making money, or they would not sell / ship for so little.   >So far everything I have ordered has met my expectations. Some >simiconductors dont. Friend ordered about $ 25 worth of transistors >(about 8 of them) and they were all bad.   I hope you got a refund... >battery terminal. They are usually less than $ 20 and will test about >anything you hook to it that will work at 9 volts or less. Best spent >money for testing I have ever seen.   While I'm interested in this, I have to ask what makes this any better than a common VOM?   I remember back in the 70s I took a cheap pocket transistor radio, connected a 600V paper cap (something like a .05) to the volume control in that radio, and connected some shielded wire to that cap and put a test lead probe on the other end. That was very handy for testing the audio stages and even some RF stages in both tube and transistor radios, while the device being tested was turned on. (If I no longer heard any sound, I'd know I hit the problem spot.   I wish I could remember how that was made exactly.... I think I found that in Popular Electronics or some other magazine.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 01 10:03AM -0500 In article <3oedbc93vn1pagkurdhrjtp0h611q295mu@4ax.com>, oldschool@tubes.com says... > >money for testing I have ever seen.   > While I'm interested in this, I have to ask what makes this any better > than a common VOM?   To explain that you just have to look at the item on Ebay. You get a lcd display and PC board that you have 3 leads comming out of it. Take most any component and hook any of the leads to the component, 2 leads if a capacitor, resistor, inductor, 3 if it is a transisitor. Push a button and in about 2 seconds the display will tell you what kind of device it is, the value of it, and if a diode or transistor which lead is which of the component.   There is a company that makes a similar device in a nice case called Peak. They sell for about $ 100 but you need two as one is for simiconductors and the other is for the passive components.   Here is an example from Ebay.   http://www.ebay.com/itm/Mega328-Transistor-Tester-Diode-Triode- Capacitance-LCD-ESR-Meter-LCR-MOS-PNP-NPN-/271611840945? hash=item3f3d53c9b1:g:XOIAAOSwd4tUHHFp   It is also Ebay item number:271611840945   The one I have is accurate enough to tell if the component should work in most circits.   Sometimes it may get fooled as when testing the very old Germanium transistors. Swapping the leads around oftenclears up this problem.

"pfjw@aol.com" <pfjw@aol.com>: Mar 01 08:28AM -0800 The single-item or combined-to-single-order for non-alcoholic, non-tobacco, non-pharmaceutical goods from outside the US to the US is $800 with some exceptions.   Many Chinese sellers use a US shadow address to avoid even this limit, with the Chinese supplier acting as a 'shipping agent' for the US address. In this case, the item is technically of US origin. And in the listing, the 'location' will be this shadow address, not China.   Put another way, don't worry about it.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Feb 28 11:06PM -0800 Clifford Heath wrote: > (though his reference to 30W/tube says he meant 6L6GC).   > He was asking about 813 (transmitting) tubes in an audio amp.   > Phil was right. Now can we please end this pissing match?   ** I only wanted to point out that regular 6L6 type tubes, as sold in the last 40 years, can output 100W per pair under the right supply conditions - something the data books do not mention.   It all about raising up the plate supply voltage while keeping the screen supply under 400V - plus matching the load correctly.   The 813 has fairly similar restrictions on the screen supply voltage.       .... Phil

jurb6006@gmail.com: Feb 28 11:56PM -0800 >"It all about raising up the plate supply voltage while keeping the screen supply under 400V - plus matching the load correctly. "   Seems to me to would have to load is pretty heavily, not just to get the power, but also to try to keep the plate volage down. If you go to 2X 700 volts, it might not be a matter of the tubes, it might be the tubes sockets.   What does limiting the G2 do ? Keep it from arcing to the suppressor grid ? I have wondered before about why the hell doesn't all this shit just arc and weld itself together. Well, OK I know it has to do with the vacuum, but still.   However wiki reports that permissivity of air at STP is only something like 1.000 point whatever, with 1 being the standard.

oldschool@tubes.com: Mar 01 06:12AM -0600 On Wed, 1 Mar 2017 17:18:14 +1100, Clifford Heath <no.spam@please.net> wrote:   >(though his reference to 30W/tube says he meant 6L6GC).   >He was asking about 813 (transmitting) tubes in an audio amp.   >Phil was right. Now can we please end this pissing match?   I just referred to the common audio output tubes. Wondering if a transmitter tube (like an 813) is capable of audio output power in the same wattage as that same tube would put out as a transmitter (asuming the plate voltage, biasing, and signal input to the tube was about the same.   From this thead, I did learn that these tubes need a lot higher plate voltages than I thought (like 1500 to 2500 volts).   I also learned (after doing some research on the web), that the original metal 6L6 tubes, did not have the same power output as the glass version. <<<I NEVER KNEW THERE WAS A DIFFERENCE IN THE CHARACTERISTICS>>> I thought they were the same tube in a different container.   *** And this explains something that occurred 40 some years ago. When I was running my tube power amps for my stereo, (four 6L6GC tubes Push-Pull Parallel, in each mono block amp), one of the tubes went bad. I went to my box of used tubes and found a 6L6 metal case, and used that for a temporary replacement. Although that tube tested GOOD, the amp just did not sound or perform properly. It did work, but lacked a lot of the "punch" it had before. A few days later I bought a new 6L6GC, and the amp worked great once again.   Now, 40 some years later, I learned why that metal 6L6 did not work properly !!!!   I also learned in recent times that for best performance, a pair or quad of output tubes should be MATCHED. Back then, I never knew anything about matching. If it was the proper numbered tube, and a tube that tested good, I'd just plug it in and GO....

Ralph Mowery <rmowery28146@earthlink.net>: Mar 01 09:48AM -0500 In article <hbcdbcd458uti9s8s0hm9vnpsul65v6dap@4ax.com>, oldschool@tubes.com says... > of output tubes should be MATCHED. Back then, I never knew anything > about matching. If it was the proper numbered tube, and a tube that > tested good, I'd just plug it in and GO....   The short answer is that most of the tubes will put out the same power at audio as they will at RF. Not counting some specific tubes such as the microwave tubes. Tubes start loosing efficency as the frequency goes higher into the RF ranges. The common 6146 tube might put out about 50 watts up to about 50 MHz but will work to 150 MHz but only put out 30 watts and stay within the ratings.   There is one other thing to look at. That is the class of service. Running class C will put out the most power but can only be used for certain types of RF signals due ot the distortion. It can not be used at all for normal audio amplifiers.   As with the 813 tube, most tubes rated for much over 50 watts output will often have a plate voltage of over 1000 volts,many like to have 2000 volts or more.   For the best sound the tubes should be matched. They are operated in what is called a push-pull circuit. Often close to class B. That is when one tube is putting out power,the other tube isn't during a cycle. It is at the crossover point that if they are not well matched you get most of the distortion. Many audio amps often operate more like AB class to help eliminate that problem. It is not much of a problem at RF due to the way the output circuit works.

Boris Mohar <borism_void_@sympatico.ca>: Mar 01 08:58AM -0500 On Mon, 27 Feb 2017 19:26:17 -0800 (PST), Phil Allison <pallison49@gmail.com> wrote:     >Since the load current is 50mA max, a low powered heater is enough - 1.25V and 200ma do the job.   >The 1.25V needed is conveniently derived by a single turn around the HOT core, carried out with wire insulted to stand 20kV or more.   >.... Phil   God you are old. -- Boris   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Mar 01 04:38AM -0800 The troll is back, please DON'T FEED THE TROLL.

gadgetsservicecentre@gmail.com: Mar 01 04:14AM -0800 Here the Whirlpool LG Authorized repair Service Center in Hyderabad is ready to work on major problem to bring winning result on the same day with no risk

jurb6006@gmail.com: Mar 01 12:13AM -0800 >"looks like it's a synchronization signal to display a vertical bar moving with the electronic memory tuning. I didn't go into much details, but seems it's not going anywhere else (and it can be removed for old sets without digital memories). "   If you can get a wire through that core you ggot it licked. I can't even count how many times I "fixed" an H-K short by just "wrapping the flytback" which gave the CRT a totally gloating heater and fixed the problem.   You need a scope to see how much voltage you get. For a CRT filament we needed 22 volt peak to peak to get the 6.3 volts RMS, but you do not have that problem.   The bottom line here is that you might have no other options. I dealt with that quite a bit, flybacks had all their pins but were tuned wrong or whatever, I had to pad quite a few with extra capacvirots on the HOT. (LOPT)   I would talk to the manufacturer, but unfortunately due to the nature of the business he miogh just say "We cannot do that, we will give you a refund". Well as we know, that does not work.

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