The transformer has a constant impedance in the whole frequency band, which can effectively solve the matching problem of single-ended and balance. Adopt simple and effective design schemes and means for transformer conversion. Strong impedance matching, good effect and low distortion. It can isolate and eliminate the digital sound of the digital circuit. The midrange and treble are soft and transparent, the details are rich, the bass is thick and powerful, and the elasticity is good. Its charm is beyond comparison of active integrated chip conversion.
The signal-free 2x amplifier 10K: 90K permalloy transformer is suitable for CD, MP3, mobile phone, computer, multimedia audio source input. The signal output by this machine is doubled and amplified. Note: The volume is not 3 times larger, the volume and voltage are logarithmic, see the bottom introduction for details.
The 1: 3 step-up transformer can make up for the passive step-up transformers produced by the low sound signal output of computers and mobile phones on the existing market. When using mobile phones, computers, and MP3 receivers to listen to music, it is generally found that the sound is small, the details are small, the dynamic is thin, and there is no CD player / decoder to full and beautiful, because the main voltage of the mobile phone and computer is 5V, and the audio output value is 0.2-0.5V voltage, and the existing power amplifier is generally designed to input voltage in 0.75-1.2V. This voltage difference requires a boost value of 2-3 times amplification. 10K: 90K signal booster transformer can make up for this gap.
Compared with 10K transformers and 600Ω transformers, 10K is better due to the large impedance and more coupling coefficients, and the more turns and more inductance, the lower frequency will be greatly improved. 10K is lighter in load and less distorted than the previous stage. The JENSEN JT-11P-1HPC 10K: 10K audio isolation transformer used by the American JENSEN JT-11P-1HPC 10K: 10K impedance is reasonable.
10K: 90K E19 Permalloy audio signal isolation transformer: measured frequency response: 10Hz ~ 38KHz -3.2DB, 20Hz ~ 27KHz -1.8DB, paired for sale! The measured value is marked on the transformer, and the two transformers are welded on the circuit board.
Wrapped with imported Permalloy material, iron core size: 19mm × height 16mm × stack thickness about 15mm.
The stack thickness of Taobao E19 Permalloy transformer is mostly 5mm, this stack is about 15mm thick, and the core material is nearly 3 times more.
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High-purity oxygen-free copper enameled wire layered winding, nylon skeleton, high-purity oxygen-free copper enameled wire layered winding, can filter out the AC noise interference caused by the equipment common ground. It has good isolation effect.
The average measured transformer: the primary and secondary copper resistance inductance is as shown below.
Test equipment: VICTOR victory 4090B desktop digital precision bridge 100HZ frequency test shall prevail, if you have an instrument, you can check it yourself.
The inductance value will be different according to the test frequency point, the inductance value is low and the inductance is high, and the inductance value is high and the inductance is small. So don't just look at the size of the inductor, but also know the test frequency, so that it makes sense.
There is also a transformer with a shielded copper-plated iron cover / round cover. The transformer and the cover are welded on the circuit board for effective isolation and drying. Both the transformer and the cover are welded on the circuit board.
The color of the cover is green and silver, and it is shipped randomly.
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The finished board and finished machine assembled with this transformer. High-quality six-potentiometer assembly, good balance, small left and right errors. Japanese rubber knob, rubber anti-skid machine feet with iron shell.
The shell size of the machine is the same as that of the American Jensen 10K: 10K audio isolator. It is 110mm long x 65mm deep x 32mm high. The iron shell effectively shields the electric field, stray magnetic fields and other external pollution and makes the background quiet. Gold-plated RCA socket, excellent contact performance.
Usage: Please use according to the logo on the cabinet, two-channel signal input, output volume after controlled by the internal transformer and potentiometer, simple operation and convenient use
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The relationship between volume (level sound pressure) and voltage level sound pressure refers to the relative ratio of the amount of electricity under the same impedance at two or several points in the circuit. The electric quantity here naturally refers to "electric power", "voltage", "current", and the multiple is converted to logarithm, which is expressed in "decibels" and is recorded as "dB". Recorded as: 10lg (P2 / P1), 20lg (U2 / U1), 20lg (I2 / I1). In the above formula, P, U and I are electric power, voltage and current, respectively. There are two advantages to using "dB": One: easy to read and write and easy to calculate. For example, if the total magnification of a multi-stage amplifier is multiplied by the magnification of each stage, the decibel can be added instead. Second: it can faithfully reflect people's perception of sound. Practice has proved that when the decibel number of the sound is doubled or decreased, the hearing loudness of the human ear is also doubled. That is, the hearing of the human ear is proportional to the decibel number of the sound power. For example, the difference between the sound of mosquitoes and the sound of a cannon is 1 million times, but the difference in human perception is only 60 times, and 1 million times is exactly 60dB. Third: The above is the "relative level", which is the ratio of the two power. There is also an absolute level-with 1mW power on a 600Ω resistor (at this time the voltage is 0.775V and the current is 1.291mA) as a reference standard, recorded as 0 level. Fourth: In simple terms, the higher the level, the greater the volume of the sound.
