To prevent damage to equipment, it would be wise to double check with a good tube manual before actually doing a substitution. Zook, k9sth probably the most used tube of all times in the final amplifier of boat anchor transmitters is the 6146. In fact, during the early 1960s rca had a series of. Still, id like to have a spare on hand thats not a chinese tube. But if it is microphonic, it may still be a fun tube to try in your phaseinverter position if youve got a 12ax7 there now microphony will not be a problem in the pi. Nov 18, 2011 whats the status on new old stock american 12by7a driver tubes. Ptfe has the lowest coefficient of friction of all polymers.
Ge essential characteristics, the whole 228 page book in an indexed pdf file big, 11mb. The series shares the eia 9bf pinout with a number of other miniature pentode tubes of the era. As of 3505, i have finished scanning the general section, receiving tubes part 1, receiving tubes part 2, miscellaneous, specialpurpose receivingtype tubes, thyratron, ignitron, and glowdischarge tubes, and most of the transmitting tubes, as well as all. If you are looking for a radio or tv tube thats not listed, ask us. It was discovered early on that it would make a splendid crystal oscillator for ham rigs and driver tubes for the higher power transmitters. Valve vacuum tube data sheets and application notes keith snook. Substitutes are given as a guide only please refer to original manufacturers data sheets to ensure that a substitute is safe and appropriate for your application. Also, it looks good as an accompaniment to the preamps. My 830s is still on its original japanese clone tube.
Another consideration is that they are relatively inexpensive on ebay, and you can risk trying a sample or two. If youre lucky, you may get a relatively nonmicrophonic one. Interesting tube discovery ecc83212dw7 volume reduction. Are there still a lot of american ge, rca driver tubes and the like around. I then tested them in a radio, and not one of them failed to operate the radio. My guess is that there were lots of 12sq7s replace in the past that were just fine. Try this tube for some interesting gain reduction effects on certain amps. You reach this tube or valve page from a search after clicking the tubes tab or by clicking a tube on a radio model page. Lots of gain, good isolation from input to output, reasonable power level handling capabilities, good high frequency use and cheap at the time. I recently tested up a large batch of tubes, and two of my testers failed 18 of the 12sq7s. All our tubes are hand tested before they are shipped out to you. This file is a part of dieters nixie and display tubes data archive.
Swagelok tube fittings is that the tubing must be softer than the fitting. Made in russia, these premium driver tubes are compatible with any 12bh7 tube. Jan, 2006 the 12bh7a is electrically identical to the 12bh7. The 12bv7, 12by7, 12by7a, and equivalents were a class of mediumlow gain, pentode vacuum tube amplifiers using the noval socket configuration. For many years now i have been scanning and posting radio service data sheets like this one featuring the colonial model 652, 5 tube broadcast shortwave superheterodyne radio receiver for many years now. Although originally marketed as pentode tubes for use in early television receivers, they found additional uses in audio and radiotelephone equipment. Buy low price, high quality 12ax7 with worldwide shipping on aliexpress.
From the early 1950s until at least the 1980s, the 6146 found its way into virtually every manufacturers line of transmitters. The 12by7a is a 1950s video amplifier output valve designed for boosting wideband tv video signals to a sufficiently high level to be transmitted over a considerable length of cable without loss of quality. If you have never used this facility before, click the help link. Tubes in the tube column are directly replaceable with tubes in the replacement column. Tube 12by7a or rohre 12by7a id3788, beam power tube, noval, b9a and shown. You will find thousands of tubes or valves with interesting links. With that in mind, the first thing to do when designing an amp like this is to choose an operating point for the output tube technically you start with the speaker, but i am assuming a standard 8ohm speaker.
Tube 12by7 or rohre 12by7 id5331, beam power tube, noval, b9a and shown. I am working on scanning and placing on this page the entire rca hb3 tube manual. Check out our new interesting tube facts down below. Operation and operating points are identical, but it is also possible to use the eml. The only difference between the two is that the heater of the 12bh7a is designed for use in seriesstring heater circuits in tv sets the tube was used as a vertical oscillatoroutput tube in tvs, as well in other applications. Surplus sales of nebraska has 25,000 pcs of this valuable little peanut tube on hand. I cant verify that the tube power supply has sonic benefit over the ss version.
So most ham manufacturers jumped on it from the start and used it until the end of tube sets. Makers describe the 12by7a as a pentode but the construction is as a beam tetrode. The 12by7 and 12by7a were, in my opinion, one of the most common 9 pin miniature tubes used. The key to selecting proper tubing for use with metal. The kenwood ts830 uses one for a driver and that is early 1980s. Welcome to the tube data sheet locator, a popular web resource for finding data on vacuum tubes. You even can look up radio models with a certain tube line up. Chances are we have it, but it hasnt been listed yet. The tube data for the 12b4a from duncan amps suggests an operating point of 150v on the plate and 35ma with bias set at 17. You reach this tube or valve page from a search after. Datasheet for qs301 nixie tubes from an unknown chinese tube data book.
The eml50 is equivalent to the historical originals by rca. May 31, 2004 i have the tube rectified version due to lloyds and craigs suggestion on it being easier on startup. I can imagine all those drug store tube testers failing them left and right. It does have a soft startup, which should prolong the life of filter capacitors and tubes. According to online dialogue on these small thyratrons, they were initially developed for controlling incandescent lamps, electromechanical relays or solenoids, for bidirectional counters, to perform various functions in dekatron calculators, for voltage threshold detectors in rc timers, etc. Mar 24, 2014 the 12by7a is a 1950s video amplifier output valve designed for boosting wideband tv video signals to a sufficiently high level to be transmitted over a considerable length of cable without loss of quality. One side has a gain factor of 100 the other side has a gain factor of 20.