tag:blogger.com,1999:blog-2098337119765190876.post7618134461390384221..comments2024-03-28T10:26:22.413+01:00Comments on VinylSavor: Tube of the Month: The 866AVinylSavorhttp://www.blogger.com/profile/03255472557028244395noreply@blogger.comBlogger15125tag:blogger.com,1999:blog-2098337119765190876.post-11009821188001477502018-06-20T21:50:29.439+02:002018-06-20T21:50:29.439+02:00Hi!
There cold be various reasons for the failures...Hi!<br />There cold be various reasons for the failures of the tubes. Difficult to say without thorough analysis what is going on. 1616 is a vacuum rectifier which has higher voltage drop than MV tubes.<br /><br />ThomasVinylSavorhttps://www.blogger.com/profile/03255472557028244395noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-59903570364236476802018-06-20T20:03:40.154+02:002018-06-20T20:03:40.154+02:00Thomas, I am finishing up a PS of your design for ...Thomas, I am finishing up a PS of your design for my 300b amp. I used a lundahl xformer to get the 550 a vintage utc for the split 2.5 10A and two 10H Lundahl chokes with 80 uf in between as you have designed it. I went thru two 866a's and a 1616 pretty quick before getting to pairs of each that have continued to work. The failures seem to be because of their age?, - not much more i could do, I gave each tube a generous warm up period before bringing on the B+. I've noticed a difference in volt drop between the 866a and the 1616 can you confirm this for me. The B+ came in at 423v. To get up to the target 445-50v for my 300b amps i've put a .85uf cap across the first choke which brought the voltage up 23volts. any suggestions. I'll share some pics soon. best wishes, DavidDavid Schatzhttps://www.blogger.com/profile/14293126255996378824noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-54179021068773751152017-04-14T20:49:52.614+02:002017-04-14T20:49:52.614+02:00If you are unsure if you can trust your own simula...If you are unsure if you can trust your own simulations, why not simply get the right power transformer and use these tubes with choke input as they are intended to be used? Power transformers are not that expensive. And it would give a much better power supplyVinylSavorhttps://www.blogger.com/profile/03255472557028244395noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-52456772541153437352017-04-14T19:25:59.486+02:002017-04-14T19:25:59.486+02:00I did a bit of homework in PSUD for a 250mA/350VDC...I did a bit of homework in PSUD for a 250mA/350VDC application. My transformer needs a choke input to get there as it has only 290VAC. <br /><br />So, when I simulated it with a 30uF input cap and a following 8H/40Ohm choke: the peak current stays still comfortably below the 1A peak current, it looks all good, even with only 30Ohm on the secondary !<br /><br />Now, can I trust these values ?<br /><br /><br />I have read mutiple times that you have to be extremely careful when going cap input on Mercury Rectifiers. Found this nice article https://www.die-wuestens.de/iz/RECT.pdf where they specified Rt=350*1.57/1 for my example...Rt more than 500 Ohm ??? PSUD gives me completely different picture...Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-12156104390741072582016-10-13T02:29:36.085+02:002016-10-13T02:29:36.085+02:00Don't really need the nanny-state stuff on mer...Don't really need the nanny-state stuff on mercury. In the first place, the oxides of mercury are harmful, not so much the metal. Also, is anyone thinking of opening a tube and consuming it? If not, don't worry about the mercury.Richhttps://www.blogger.com/profile/02202997838689375701noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-44150927115962910852015-11-25T06:54:45.724+01:002015-11-25T06:54:45.724+01:00hi,
in the manual of the RCA is parallel.
I sea...hi,<br /> in the manual of the RCA is parallel.<br /> I searched the internet and have not found a series configuration. so I hesitated. but with your explanation I became confident with it. <br />Thanks a lot .....Thomas.<br />Best Regards<br />edEdsuwanhttps://www.blogger.com/profile/06737499884844804626noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-74032040931467072862015-11-24T11:28:54.405+01:002015-11-24T11:28:54.405+01:00Hi!
If you have two separate 2.5V windings you wil...Hi!<br />If you have two separate 2.5V windings you will have no problem with the voltages splitting equally. There is no advantage in connecting them the way you do, but also no harm. You can also simply connect one side of both heater windings to the B+ filter chain. The RCA manual states a preferred pin from which to take the B+<br /><br />ThomasVinylSavorhttps://www.blogger.com/profile/03255472557028244395noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-75689945800438588002015-11-24T11:05:45.337+01:002015-11-24T11:05:45.337+01:00Thank you for your answers.
I can be quiet for us...Thank you for your answers.<br /> I can be quiet for used that.because I have not experienced with it. <br />I have wrong to write . I mean this transformer is 0 - 2.5 Vac /7A x 2 and i make 2.5 Vac - 0 - 2.5Vac for get Center Tap. before i will use for parallel. but seeing that I was more than good with the configuration of the CT because it provides balance (I do not know whether this is true in my opinion). <br />I learned a lot from your posts here. thank you very much to you that many share knowledge.<br /><br />Thank you.<br />best regards<br />edEdsuwanhttps://www.blogger.com/profile/06737499884844804626noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-69686360136657601672015-11-19T07:54:35.639+01:002015-11-19T07:54:35.639+01:00Hi! You can wire them in series. Check that the fi...Hi! You can wire them in series. Check that the filament voltage splits evenly between the tubes. A 14A transformer might give too high voltage if loaded with 5A. Then drop with resistors. Why not get the appropriate transformer for such a project?<br /><br />ThomasVinylSavorhttps://www.blogger.com/profile/03255472557028244395noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-6424315703333999252015-11-19T04:31:07.702+01:002015-11-19T04:31:07.702+01:00hi Thomas,
I 'm building 211 Amp. i have used ...hi Thomas,<br />I 'm building 211 Amp. i have used 866A as PS.<br /> i hope you can give me advise to me.<br /><br />how configuration filament of 866A? My filament PT 2.5V - 0 -2.5 V ac / 14A<br />i apply 866A x 2 as series (5Vac) and center tap as B+.<br />Are That wrong? and must be pararel ?<br /><br />Thank you.<br />best regards<br />edEdsuwanhttps://www.blogger.com/profile/06737499884844804626noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-49776248334734474802014-12-04T03:00:59.427+01:002014-12-04T03:00:59.427+01:00Any prefference on brands?Any prefference on brands?Anonymoushttps://www.blogger.com/profile/11528028453679775804noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-71970418918457887612014-11-23T16:13:13.793+01:002014-11-23T16:13:13.793+01:00Hi!
866A or 816 would work. Check prices at the us...Hi!<br />866A or 816 would work. Check prices at the usual tube dealers. These are easy to find<br /><br />Best regards<br /><br />ThomasVinylSavorhttps://www.blogger.com/profile/03255472557028244395noreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-14165144767841802282014-11-22T16:33:32.750+01:002014-11-22T16:33:32.750+01:00I want to put an old Elmac 67 transmitter on line,...I want to put an old Elmac 67 transmitter on line, and will be building its power supply.<br /> <br />I want to use rectifiers that glow when operating, like mercury vapor. I can remember the first ham station I visited, and was impressed by the glow from the various cabinets, that fluctuated with modulation. I would like to get a little of that back, and in my shack. (My solid state equipment just sits there with no action.)<br /> <br />I will be running a maximum of about 120 mills, at 120 hz. I’m thinking of having a full wave solid state bridge feeding the tube in order to maximize the glow from the tube. This is strictly for show.<br /> <br />Can you give me some pointers as to which tubes will give me the brightest glow from this application?<br /> <br />Do you have any in stock, and what are the pricings?<br /> <br /> <br />Thank You,<br /> <br />Bernie KE7XD<br /> <br />amsandbjs@gmail.comAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-26208725685750861572011-08-11T15:00:03.084+02:002011-08-11T15:00:03.084+02:00Hi J!
I mostly use plate caps from current manufa...Hi J!<br /><br />I mostly use plate caps from current manufacture<br /><br />ThomasThomas Mayerhttp://vinylsavor.blogspot.comnoreply@blogger.comtag:blogger.com,1999:blog-2098337119765190876.post-58300342217763559942011-08-11T14:36:53.236+02:002011-08-11T14:36:53.236+02:00Nice photo of the world map, really beautiful. Do ...Nice photo of the world map, really beautiful. Do you make your own plate caps or do you use NOS?Jer.Epshttps://www.blogger.com/profile/03505967128773009552noreply@blogger.com