Any schematic of "Quickies" preamp add choke and OPTS?
I think it seem ok
No. Your headphones are low impedance and won't do well with such an arrangement unless you want to use 4 tubes.
English only please
The load impedance is very high, do the ear put words must use the output transformer, the standard use of data is the screen load impedance ra=8k, screen pressure ua=90 Volt, the curtain grid voltage g2=90 volt, grid pressure g1= minus 4.5 volts, output power po=230 MW filament best battery power, Otherwise, it introduces annoying ac noise.
Thank you very much Mr. Dragon Lord.
3Q5GT the load impedance is very high, then do use the output transformer, the standard use of data is the screen load impedance Ra = 8K, screen voltage Ua = 90 V, the grid voltage gate voltage G2 = 90 V, gate voltage G1 = Negative 4.5 volts, output power Po = 230 milliwatts
The filament is best battery-powered, otherwise it will introduce annoying AC noise
Translated of Mr. Dragon lord
3Q5GT the load impedance is very high, then do use the output transformer, the standard use of data is the screen load impedance Ra = 8K, screen voltage Ua = 90 V, the grid voltage gate voltage G2 = 90 V, gate voltage G1 = Negative 4.5 volts, output power Po = 230 milliwatts
The filament is best battery-powered, otherwise it will introduce annoying AC noise
Translated of Mr. Dragon lord
哈哈,其实我是个在校大学生啦,那本书确实很老,是1958年出版的,几年前在旧书店里看到并买下,是一本很好的书,虽然已经60年过去了,但是它至今还是中国电子管爱好者重要的参考资料之一
Haha, actually I am a university student, that book is really very old, is published in 1958, a few years ago in the old bookstore to see and buy, is a very good book, although it has been 60 years, but it is still the important reference for China's vacuum tube enthusiasts.
Haha, actually I am a university student, that book is really very old, is published in 1958, a few years ago in the old bookstore to see and buy, is a very good book, although it has been 60 years, but it is still the important reference for China's vacuum tube enthusiasts.
English only please
对不起,我的英文水平非常差,我借助翻译软件进行交流,同时附上中文原文,可以吗?
Sorry, my English is very poor, I use the translation software to communicate, but also attached to the Chinese text, can it?
An 8K:32 transformer is a 16:1 step-down. How much gain will you get from the tube? You'd really want to use some feedback since you're planning to use this tube as a pentode, and that will cost you a little more gain.
In the end, you'll put 1V into the circuit and get less than 1V out.
In the end, you'll put 1V into the circuit and get less than 1V out.
An 8K:32 transformer is a 16:1 step-down. How much gain will you get from the tube? You'd really want to use some feedback since you're planning to use this tube as a pentode, and that will cost you a little more gain.
In the end, you'll put 1V into the circuit and get less than 1V out.
手册上给的是单元运用,那个图只是功率级,一般放大器都不止一级,正常使用还要在这个的基础上加一个前级做电压放大,如1N5GT和1H5GT就是个不错的选择,阻容耦合可以很方便的自由组合,当然也可以加一个升压变压器做输入,这样就不会有增益不足的问题了
The manual is for unit use, which is just power level, general amplifiers are more than one level, the normal use of the base on this plus a front-level do voltage amplification, such as 1N5GT and 1H5GT is a good choice, resistance coupling can be very convenient combination of free, of course, can also add a step-up transformer to do the input, So there will be no gain problem.
It seem this tube might not suitable for Headphone amplifier
but rather suit to do preamplifier with 6SJ7 as Xindak VP2 Pre amp
specification seem good
S/N Ratio ≥100dB
THD 10V - 0.5% 2V - 0.13% 600mV - 0.03%~0.06%
Input Impedance 100kΩ
Output Impedance 600Ω
Number of Channels 2
Tubes 6SJ7*2, 3Q5GT/G*2, 5Z4P*1
Frequency Response 10Hz/-0.5dB ~ 100Khz+/-2dB
Headphone amp might be more suitable to use 6V6 as E400 Headphone amp.
or 6SN7 as E200 Headphone amp.
but rather suit to do preamplifier with 6SJ7 as Xindak VP2 Pre amp
specification seem good
S/N Ratio ≥100dB
THD 10V - 0.5% 2V - 0.13% 600mV - 0.03%~0.06%
Input Impedance 100kΩ
Output Impedance 600Ω
Number of Channels 2
Tubes 6SJ7*2, 3Q5GT/G*2, 5Z4P*1
Frequency Response 10Hz/-0.5dB ~ 100Khz+/-2dB
Headphone amp might be more suitable to use 6V6 as E400 Headphone amp.
or 6SN7 as E200 Headphone amp.
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3Q5 is a perfectly good headphone amp, WITH a transformer!!
It is really a "beach radio" power tube. 15 years ago I wrote:
We did take tube-radios to the parks and hills and beaches. The last time I saw one was on the beach in California (before the first time Nixon ran for President) so I call them "Beach Radios". They were heavy because they were about half batteries and you usually needed new batteries every time you went to the beach. And the speaker wasn't very loud. But they did the job.
The same amount of audio power in headphones would be deafening; we could design for lower voltage and less battery drain.
The wiring on a battery-filament design is very strange to eyes that are accustomed to separate cathodes. Because all the heaters must be connected together, all the cathodes are grounded. That makes the usual form of self-bias cathode resistor impossible. These tubes were designed to work with some tricks.
The 3Q5 (or similar 3V4) will make well over 200mW in a 8K load. To do that it needs 4.5V peak or 3Vrms, more than many preamps, DACs, iPods deliver. However headphones will be happy with 1/4 of 200mW, so we only need half this audio voltage.
The attachment shows a Beach Radio, and a cut-down with just the power stage.
It is really a "beach radio" power tube. 15 years ago I wrote:
We did take tube-radios to the parks and hills and beaches. The last time I saw one was on the beach in California (before the first time Nixon ran for President) so I call them "Beach Radios". They were heavy because they were about half batteries and you usually needed new batteries every time you went to the beach. And the speaker wasn't very loud. But they did the job.
The same amount of audio power in headphones would be deafening; we could design for lower voltage and less battery drain.
The wiring on a battery-filament design is very strange to eyes that are accustomed to separate cathodes. Because all the heaters must be connected together, all the cathodes are grounded. That makes the usual form of self-bias cathode resistor impossible. These tubes were designed to work with some tricks.
The 3Q5 (or similar 3V4) will make well over 200mW in a 8K load. To do that it needs 4.5V peak or 3Vrms, more than many preamps, DACs, iPods deliver. However headphones will be happy with 1/4 of 200mW, so we only need half this audio voltage.
The attachment shows a Beach Radio, and a cut-down with just the power stage.
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