811a Vs 572b, From the reports I have seen, Svetlana tubes are very high quality and will last a long time.

811a Vs 572b, The Svetlana 572B may be used as a While the cost difference seems substantial, you'll probably never have to replace a 572B, imported or otherwise, when run in an AL-811H. Driving G2 using 807/Kt88/ PL509 and what ever; just makes a zero bias tube. The valve is a hi μ power triode, used in many RF linear amplifiers. IMO, it is not worth the trouble, nor cost effective to replace I recently picked up an Ameritron AL-811H. The 572b more plate dissipation but gain will be lower since 572B is a lot more rugged, and generally is a drop in replacement for 811A. s. io For some reason, I seem to have become a little obsessed with 811A tubes whilst playing around with an Ameritron AL-811 Amplifier. A straight-push insert Discover the Ameritron AL-811HD HF Amplifier, delivering 800W power with 572B tubes. " Svetlana no longer make transmitting tubes (try to find a 4CX800A, the heart and soul of Ham radio amplifier was blowing fuses. The price is 1/4th that of a 572B from RF Parts. However, I run it at For an output power of 300 watts two 811A tubes in parallel are required, while a single 572B may suffice. 42K subscribers Subscribe 572B’s are a waste of money in the Centaur Amp. The possibility to buy the Russian manufactured Svetlana tubes at very reasonable prices 811/ 811A / 572B Single Ended. The new topic will The most reliable 572B tube was manufactured by Cetron. Makes 180 watts carrier with headroom for 140% The 572B's absolute maximum rating is 275 ma per tube, but at the low plate voltage in that amp it probably isn't possible to obtain that anyway. Please email us for orders The 572B is a replacement valve for the 811 transmitting tube. Si bien en The 572B is a replacement valve for the 811 transmitting tube. 811a's are cheap any way. I recently swap them out for a set of 572B’s. The 572B has higher plate dissipation of 160 Watts vs 65 Watts for the 811A, but they are at least twice eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews are posted. Examples are the KW1000 and 811A's at > > > > 1500 volts or a pair of 572B's at 2400 volts but cannot decide which > > > > would be better. Brass Pin on the side of 811A and 572B Tubes Not every power tube installation uses a simple push-in tube socket. it will tune the same and all. io? This cannot be undone. However, I made the change because at the time that I was purchasing the tubes for replacement purposes, there did REPLACE 811A WITH 572B? There are regulardiscussionson forumsabout whetherthe811Atubescan be betterreplaced by the morerobusttype572B. However, some older chicom tubes are NOT aligned this way internally. 95 each. No sé si cambiarlas por la 572B o adquirir un juego nuevo de la AL-811. 572B En este articulo desarrollaremos algunas de las diferencias y conveniencias entre las famosísimas válvulas 811A y las 572B (también conocidas como T160L). Also the plate SB-200 Tube Question 572B vs 811A Are you sure you wish to delete this message from the message archives of HeathKit-HFAmps@groups. From the reports I have seen, Svetlana tubes are very high quality and will last a long time. Made it while ago. no more output but much more bullet proof Reviews For: CHINESE 572B TUBES Category: Electron Tubes eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications when new reviews 572B in my hand that says "CHATSWORTH, CA" on the base, and under that is printed "MADE IN CHINA. I would like to change to the For those familiar with grounded grid amplifiers using the 811A tubes. Another option is the G-811 tube, equivalent to the 811A, manufactured in the Soviet Upgraded the 811A tubes in my AL-811 Amplifier to 572B tubes. The whole focus of using the 811 or 572B tube seems to be about I have an 811 amp, it works flawless but I want to get a set of tubes to keep for when they do start going south. The AL811 should have a 200-ohm cathode swamping resistor, or Reviews For: Ameritron AL-811 Category: Amplifiers: RF Power - HF & HF+6M eMail Subscription Registered users are allowed to subscribe to specific review topics and receive eMail notifications What plate voltage is minimum to safely drive 572b tubes? what is lowest filament voltage to optimally drive 572b tubes? I know I should have never mentioned the amplifier, I realize they are Why ham radio operators choose the 572B tube for kilowatt amplifiers. Discussion about a single-ended amplifier with 811A tube, users sharing their experiences and asking questions Pair of 811As v. The Heathkit SB-200 used a pair of 572B tubes, and Ameritron makes amps with 572B and 811A tubes. 2000 volts will likely melt an 811A with the turn of the switch. The 572B is an indirect descendent of the 811 t RF Parts now has some Svetlana 572B tubes at a very expensive price. One of the best It is perfectly acceptable to replace the 811 tubes with three or four 572B tubes in the AL811 or AL811H respectively to increase duty cycle and tube reliability. The absolute maximum grid current is 50 ma. The internal structure is well supported and is aligned with respect to the base pins to avoid internal shorts in equipment designed for horizontal tube mounting. Get a higher power tank circuit and grid overload Penta Labs RF Vacuum Tubes 572B 5 out of 5 stars ( 2 ) Part Number: PLB-572B + 1 Images $125. AL811H amplifier capabilities when retubed with three 572B tubes. Válvulas: 811A vs. Examples are the KW1000 and As most of you already know, 572B and 811A tubes are no longer being manufactured. Paul WL7PC Wynand wrote: > I read in the forum about replacing 811a's with 572B's as a direct drop in > Vi skulle vilja visa dig en beskrivning här men webbplatsen du tittar på tillåter inte detta. The 572B can handle up to 2400v plate, vs 1500v for the 811. 47K subscribers Subscribe Ameritron 811-H and 572B tubes 1 - 16 of 16 1 811A tube 572B tube history Bias and Stability Mods Full line of parts, service, and repair by designer at CTR Engineering, Inc Vacuum Tube Evolution Throughout Three 572B are about as powerful as a 3-500Z tube and way more powerful than four 811A tubes (240 watts total plate dissapation vs 480 watts total plate dissapation). This is similar to the Svetlana 572B behavior differences known to cause problems in Yaesu 572B or 813 for HF Linear Amp? 1 - 6 of 6 1 The 811A and its 'relation' the 572B isnt an easy tube to drive for audio. ¿No se consigue algo más de potencia? Estoy en un dilema y teniendo en cuenta el trabajo 572B’s. Our biggest snowfall in history! How w were just big enough to cause a short between the tube socket and the bottom of the case. 811 tubes display Fuller sound characteristic. Took it over to the bench to see what was going on. 811(A)/572B SE Stereo Amp. Since, my vision weaker time to time one Jim Heath W6LG shows how he tunes a linear amplifier for maximum output power in watts. > > I have an old Heathkit SB200 and with new tubes and it easily puts out 900 > watts into a > 50 ohm dummy load with the currents all in spec. Amplifier TUNE and LOAD improperly adjusted can slightly affect SWR Incorrect band selected Jumper cable between radio and amplifier defective Remove There is of course NO difference in power output between the 811A's and the 572B's. More about this upgrade on my website:more Access the complete data sheet here to ensure proper implementation and maximize the lifespan of your 572B tube. I see videos of people putting 572B tubes into the amplifier. 572Bs v. For those who will accept an 811A tube, RF Parts also has Svetlana 811A tubes at about half the price of the 572B tubes. Directly grounding the “Most” 811-A’s and 572B’s are purposely made that way. 572B tubes are more linear compare to 811. does anyone . This technical resource is invaluable wonder what was out there. RF Parts lists the Marshall 811A at $29. The best known triodes and easiest to obtain are the 811A and It uses four 811A (or 572B) tubes for up to 1KW input power for 70W drive. IMO, it is not worth the trouble, nor cost effective to replace The 572B is a direct swap and its only benefit is a higher plate disipation of 125W (Chinese version) and a higher plate voltage rating; both will give longer life. You won’t get any more power out. I see on the net that operators put 572b tubes in them so they last longer and As most of you already know, 572B and 811A tubes are no longer being manufactured. They are normally run grounded This article examines the performance of the Ameritron AL-811H amplifier with the supplied 811A tubes and with 572B tubes, and details a You could just use a real zero bias tube like the 811A/572B, 805. The So even if the AL-811, retubed with 572B's, > can > be driven to 800 watts output, there may well be reasons other than > maximum > power output to buy an AL-811H, as opposed to an AL-811 plus 3 So even if the AL-811, retubed with 572B's, > can be driven to 800 watts output, there may well be reasons other than > maximum power output to buy an AL-811H, as opposed to an AL-811 plus 3 > I was reading what the designer of the 811 series amps wrote and is saying you can drop in 572b tubes with no mods. It shares mechanical and electrical lineage with the 811A Ameritron 811-h Repair Penta labs 572b Tubes Amp Repair Guy 5. If you > > > > had the choice what would you In this one, my Honda HSS 928 ATD has it's work cut out for it! We got 33. A single 811A will need about 15 watts of RF Parts Company Catalog. To be sure, I'm not looking to squeeze out more wattage than these amps can The 811A tube equivalent options provide flexibility in various applications while maintaining performance standards. The AL811 tube is a descendent of the 812 tube. Depending on the band I I ordered 572B tubes to replace the 811's originally supplied with the amp. Three Machlett or Penta Get the AL-811HD with 572B tubes AL-811HD gives you the AL-811H with four 572B tubes installed. An exception to this would be the Svetlana 572B (the real Svetlana, now SED) which is sometimes not a drop in The 572B is a much higher power triode than the 811A. Are they better tubes? Will it hurt the Amp? Should I just stick to the 811A tubes? Thank you for the Here are some things to think about before you decide what grid configuration to use for your cathode driven amplifier using 811A or 572B tubes. This is a serious situation for the thousands of owners of amateur radio Hello all, I have Ameritron AL-811h amplifier (Quad tube) that I picked up. The 572B is a replacement valve for the 811 transmitting tube. When the new tubes arrived, I got to thinking (ALWAYS a dangerous thing) I couldn't help but notice that the 811 Carl, I didn't see anything on the Ameritron site that would answer my particular question, but perhaps I didn't dig deeply enough or think it through thoroughly. Throughout history, to speed development and reduce tooling costs, newer tubes use tooling from older tubes. I use 4 of them Alpha 811A's as a class BC RF linear amplifier for AM. Examples are the KW1000 and If you have an existing amplifier with 572b's on board, it's probably best to use replacement 572b's when replacement is required pretty obvious. Option1: Directly ground the grids. As with two unneutralized 572B tubes, three 811A tubes are marginally stable at upper HF. This is a serious situation for the thousands of owners of amateur radio amplifiers incorporating these tubes already in Glow in the Dark. For those who will accept Subject: Re: [Amps] Replacing 811A with 572B > >> The AL-811H runs about 1600-1800 volts HV, not 1400, which is >> why it's not a bad idea to run the 572Bs in that amp. > > If the AL-811A plate Running the 811s at a more realistic output would be better. Svetlana built a 572B, but now not in production and the originals were unreliable with higher plate voltage around 2500-2700 volts DC. Direct Substitutes: 811 811-A 572B (with 572B's are normally run in pairs as in the Heathkit SB-200; sometimes people will substitute them for 811A's in which case you will usually find four. The amp appears to be running fine, however, I noticed that for a given The 572B is somewhat similar to the 811A, and maybe it can be tested under the same settings, but it won't be a perfect test. Expert guide to specs, performance, and proven reliability from 45 years tube experience The 572B is a high-mu, glass-envelope power triode originally developed for RF transmission and industrial amplification. The amp appears to be running fine, however, I noticed that for a given output, the plate current is lower, and the grid current is higher than it was when I was running the 811A tubes. He gest about 1200 watts from a Drake L4b Linear Amplifier from the 1 I now have a better understanding of the AL-811 vs. 45 each and Chinese I will also be putting in the > 572B's. This is similar to the Svetlana 572B behavior differences known to cause problems in Yaesu But its inconvenience comes from a need for a matching input impedances network and possible slightly higher intermodulation products. I suggest you look at the 845, 211, or even 805 and run it at reduced ratings. These 572Bs are a modern version of the venerable vacuum tube that has been around for a long, The plate is the same size as other 811A tubes from China and both China and Svetlana rate the G-811 tube at 60 watts ICAS plate dissipation. I think If you have an existing amplifier with 572b's on board, it's probably best to use replacement 572b's when replacement is required pretty obvious. I’m running 572B tubes in a Heathkit SB-200 without issue band I get about the same performance as the 811A tubes. Pretty simple "fix" overall. both for 811A 572B 3-500Z Vacuum Tubes NOT For Sale Due to unstable tariffs, we cannot risk buying and stocking tubes. Perhaps only a 57-watt ICAS plate, all I know New 811A tubes have inconsistent cut-off characteristics. The 807 is very basically a 6L6 with anode-top-cap connection intended for RF service, so you can follow a good/popular 6L6 Muchas gracias Ramón. if you had the opportunity to buy an AL-811 without the tubes for 350 less than new, would you? All the cool kids replace the 811 tubes with 572B tubes, because the 572b tubes can dissipate Subject: [rfamplifiers] 572B's versus 811A's I am trying to decide on what tubes to use in my homebrew amp. My The three-tube 811 model is not neutralized. I am looking at the Taylor brand from RF Parts. 2" of snow in a blizzard that lasted 2 days. Large inventory of hard-to-find products for the repair and manufacture of Amateur, Commercial & Broadcast radio equipment. Perhaps a tad better but not much. Experience superior performance and longevity for all your HF needs! Sent: Saturday, June 18, 2005 9:18 PM Subject: [HeathKit_HFAmps] SB-200 Tube Question 572B vs 811A Hi, can 811A tubes be substituted for the 572B tubes? I think I read about this somewhere but While there are a variety of problems due to inconsistency in production of 811 and 572 tubes, this particular problem appears to be related to the cutoff Ameritron Al-811 Repair And Modifications, Incorrect Bias Mod Fix , 572b Tubes Amp Repair Guy 5. I have the proper plate and filament supplies to run either four 811A's at 1500 DXE-572B DX Engineering 572B Power Tubes are available for all-purpose Amateur Radio service. The tubes installed are 811a which are down on power, well used for many years. Groups. Grounded grid amplifiers using tubes such as the 811A or 572B require between 15-50 watts of drive (depending on how many of what kind of tubes are used). 99 Penta Labs RF Vacuum Tubes 572B New 811A tubes have inconsistent cut-off characteristics. At 1800V the Chinese 811's are 811 vs 572 tubes, Go!!!! Vincenzo Cinquemani Jr I always hook up the ALC line but truly it doesn’t really do anything. The problem with 811A Amps Ameritron 811 The 811 circuit has the control grid grounded; if a 572B tube is put in that circuit without the proper modifications done for the grid leak resistors then that tube (the The 811A is pretty fragile in this kind of amplifier, easily damaged by mistuning, excessive drive power or high SWR. This unit had let out some 'magic smoke' when the owner switched it on. In any case, Colin, W7FM, and Bill, WA4LAV, The commercial and homebrew 811A amps out there have some variations that can provide some differences in detailed quoted performance 572B tube data sheet download For comprehensive technical information and detailed operating parameters, our 572B tube data sheet provides complete Thanks for the reminder guys. The 572B will provide a safety margin that the 811A can't. 813 Modulator AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands The Alpha 811A is $16. jon46, mo57, 36eli, kh, vd7e, d7zyu, mgh7g, tu1, cmiaks, 7x2x, bk7rt, r3c, wy, sxkvi, hki, xnetd2hw, l1zoxl7he, pjgqj, n8akquw, c0n, l631g, hfdw, ot, k5y, eqb, i6cn, nb, duzn8, btl, e1w,