I have a hallicrafters s76 receiver that i purchased and repaired about a year ago. Previously only available as very expensive imports from the far east, interstage transformers are believed to be the only true method of driving output valves by many. Home the canadian vintage radio society, and its bimonthly publication, canadian vintage radios, is dedicated to the preservation, restoration, collection and enjoyment of antique. There are many ways in connecting a driver to a powertube, all with the same goal. This is a universal replacement type it will replace any of the three audio.
New tube gear mostly only have an input and output transformer. I also read about the highly regarded amity and karna. May 25, 2010 when tested in a radio they performed as an audio interstage transformer and gave results very similar to that of a hammond 124a transformer. Problem when i had this problem, robert casey suggested the capacitor fix.
I should point out that my main interest is 1920s battery radios and that they are very forgiving. New universal interstage transformer, 20,000 ohm ct primary with 80,000 ohm quad split secondary. Perfect drop in replacement for audio interstage transformer for gibson white panel amps that use a transformer for phase inverter. Used it to replace a driver transformer for pp 45s in a gm253 lowboy ca. If youre antsy about that voltage you can always put this one on the detector and move a good detector one to the first audio. I have numerous times in the past used the pt156 from aes. New interstage transformers designed for singleended. If you are looking to replace radiola iiia audio transformers, check out our universal radiola replacement unit. A transformer schematic is depicted in figure 1 below. Magnetic coupling in interstage transformer is the best energy transfer mechanism for low frequency audio frequency that can be best viewed same as the force working in most dynamic loudspeaker. Silver wire windings available at current market prices.
Center tapped secondary may be used for pushpull grids. Audio interstage transformers from scrap canadian vintage. Enameled copper wire is wound round the central half of the. Somehow, it looks like some of the most expensive set amplifiers have interstage transformers like audio note or shindo. Transformers transform sound fx transformers transform sound effect, transformers transform sound fx, transformers sounds, transformers morphing noise, transformers transfor audio clips, transformers morph sound effects, tv audio sound bites free, noise mp3 download. Wide bandwidth output transformers for single ended and pushpull vacuum tube. Youtube, youtube channel, video marketing, youtuber, igtv, erika vieira, video, instagram electratone. It is a great receiver, and i have a lot of fun listening to it. Our part number 124b is the same as our 124a except for 49% nickel laminations for greater fidelity. Transformers in this category are hermetically sealed and of higher impedance than 1k ohms. Audio interstage transformer specs antique radio forums. Mouser is an authorized distributor for many signal and audio transformer.
Transformer audio interstage, 10 ma antique electronic. The product is enclosed in the square case on the left. The hammond series appears to be a larger transformer. A low current wallwart xfmrs can also do the trick. Designed for general purpose or replacement use in single ended or phase inverter tube driver circuits. Blablasise aetheradio smoothie insured financial wealth. While the ll1660, ll1692a, and ll1671 have been great transformers in my hands and in those of many others, there was performance to be gained by designing new transformers whose winding geometry has. Resistance checks showed the primary winding is open. Satellite tv equipment free delivery possible on eligible purchases. The quad split secondary arrangement each secondary section is 12 the turns of the whole primary means that as many as 4 tubes can be driven, each independently biased if wired for 1. Transformer audio interstage, 10 ma antique electronic supply.
Interstage transformers can be made in different ratios, primary currents and voltage ratings. The design of chokes, small power transformers those used in tube amplifiers and preamplifiers and audio output and interstage transformers is such a specialist topic that even most electronics engineers would not even know how and where to start, let alone produce a finished, working transformer. Just had to play with the capacitor value to get the bass response back to original. Audio transformers were originally used in valve or tube amplifiers as interstage and output transformers. The excellent magnetic properties of r core and precisely wound coil by the computerized manufacturing system achieve a wide bandwidth, low distortion, and low magnetic loss of the transformer. I also read about the highly regarded amity and karna amplifiers that d olsen built and they have also interstage transformers. View topic audio interstage transformers antique radio. This in turn has lead to improvements in tone and musicality, even if measured response has changed little. At this point, if you find the word audio transformers on its left side, please click on the word or on a small picture on the other side to see the catalog 392k in pdf file. They are homemade audio interstage coupling transformers.
The quad split secondary arrangement each secondary section is 12 the turns of the whole primary. Interstage audio transformer too old to reply nelson 20040216 05. For model audio interstage transformers for replacement, atwater kent mfg. The design of chokes, small power transformers those used in tube amplifiers and preamplifiers and. I have intermittent cracking noise i pointed out to the audio interstage transformer t8. Audio transformer and impedance matching transformer. I have used several in various radios with success.
Audio interstage transformers for radio part atwater kent mf. Transformer audio interstage, 10 ma equivalent to stancor a53c. Its important to remember that when theyre talking about audio interstage transformers, and refer to 3. Replacing any coupling capacitor with a well designed and correctly matched driver or interstage transformer yields an almost shocking improvement in sound and should be tried to fully understand. Download hundreds of free audio books, mostly classics, to your mp3 player or computer. I was told by one tech the most influential transformer in a piece of gear is the input transformer.
If youre antsy about that voltage you can always put this one on the detector and move a good detector one to. I went online and looked at audio transformers, but i am confused about what to order for a replacement. The original transformers are usually found with open windings due to the fine wire and high turns usedcoupled with age. Hedgehog transformers are occasionally encountered in homemade 1920s radios. The output voltage of a tube stage is much higher than the bias needed for the next stage, we should eliminate the dc and let only the ac arrive to the next stage. I replicated the circuit faithfully with an exception of the interstage transformers. The right on the photo is the r core audio interstage transformer in bare condition. Impedancein audio transformers even mixing consoles especially in recording work, but also in many live sound applications all depend on transformers to match the high impedances of the tubes to.
High quality audio transformers sjs electroacoustics. The signal has to be low impedant combined with enough current. Transformer audio interstage, 10 ma ce distribution. Merren audio provides custom wound transformers for both output and power applications including chokes. Original transformer primary went open after about a month when restored set started being used 23. Connect the grnyel wire to the grn wire and the blkyel wire to the blk wire. Transformers in this category are open frame of various impedance. It is no more used a lot, quality transformers are rare and so are their manufacturers. Tube amplifiers and interstage transformers audiogon.
Softone rc20 versatile audio interstage transformer. Jan 22, 2010 this may be critical on hi fi audio transformers but these old 1920s sets seem to be forgiving as noticed by the many different transformers that have been used sucessfully as replacements. This is a universal replacement type it will replace any of the three audio transformers used 1st audio driver2nd audio phase splitter stage or output transformerby correctly connectiong the 5 lugs. Wide bandwidth output transformers for single ended and pushpull vacuum tube applications. Our range of high quality audio transformers continuous to improve and expand. I notice lots of old tube gear like pultec eqs, universal audio 175s have interstage transformers. Impedancein audio transformers even mixing consoles especially in recording work, but also in many live sound applications all depend on transformers to match the high impedances of the tubes to useful interstage and output impedances. Moving coil, interstage and preamp output transformers. The allen avionics agl series employ fullyshielded, 1. Hi all, started digging into this columaire8 and find the primary on the insterstage audio. Much which follows on the topic of audio transformers is of necessity somewhat over simplified to give a general overview.
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