I very sorry my error Mr. Mlloyd1
The power supply is a universal in nature. By changing the values and figuring out the voltages drops, it can be used for both Hi and low voltages and currents.
The PSU that you are speaking of, is for low voltage, but supports high current usage, up to about 5 amps, with a fair safety margin.
Lets see, the value of C3, C2, and R3, forms a circuit that provides not only low ripple, but a small amount of surge protection. The internal R of the darlington arrangement also aids in surge protection, with the zener providing reference in conjunction with R3 and C2.
This arrangement allows the circuit to be a capacitance multiplier, up to hundreds of thousands of uf's. To figure out the overall UF's that C2 brings to the circuit, it is.
C2's value, times the gain of Q1, times the gain of Q2.
By reducing the rise and fall times, the circuit itself reduces ripple, which reduces some of the voltage surge.
At turn on, C3 will charge up, quickly at first, until it reaches reference, where it will continue to charge, slowing down large surges with the aid of R3 , C3,and the zener. So a RS, is not required. But if you desire to include an RS, you can find the formula in any Amateur Radio Handbook.
To obtain the reference value of the requested zener, any combo of zeners can be used. But if you are making a PCB, it is much easier to use one close to the value you require.
Take Care
Ivey
The power supply is a universal in nature. By changing the values and figuring out the voltages drops, it can be used for both Hi and low voltages and currents.
The PSU that you are speaking of, is for low voltage, but supports high current usage, up to about 5 amps, with a fair safety margin.
Lets see, the value of C3, C2, and R3, forms a circuit that provides not only low ripple, but a small amount of surge protection. The internal R of the darlington arrangement also aids in surge protection, with the zener providing reference in conjunction with R3 and C2.
This arrangement allows the circuit to be a capacitance multiplier, up to hundreds of thousands of uf's. To figure out the overall UF's that C2 brings to the circuit, it is.
C2's value, times the gain of Q1, times the gain of Q2.
By reducing the rise and fall times, the circuit itself reduces ripple, which reduces some of the voltage surge.
At turn on, C3 will charge up, quickly at first, until it reaches reference, where it will continue to charge, slowing down large surges with the aid of R3 , C3,and the zener. So a RS, is not required. But if you desire to include an RS, you can find the formula in any Amateur Radio Handbook.
To obtain the reference value of the requested zener, any combo of zeners can be used. But if you are making a PCB, it is much easier to use one close to the value you require.
Take Care
Ivey
More 2N2222A infor
Praznik:
I am very glad to hear from You.
Yes the operational voltage was set at 30volts DC. But that was because we had limits that we had to stay within. Just in case that a portable unit was to be built in the future, it would not tax the submarines overall battery load.
Even today, in nuclear submarines, one of the most important items is the submarines battery load.
Why?
Inport, shorepower is used to startup the nuclear reactor. It uses thousands of kilowatts to bring it up.
At sea, if the sub must restart her nuclear systems. They will need every kilowatt they can get their hands on.
One thing that I need to put not there.
In the beginning, there was not too many transistors that were available.
But today, there are thousands. So you can use the excellent 2N4401, which is like a 2N2222A, with a lower max frequency and similar switching speeds.
I am posting the beautiful layout of the 2N2222A, with PCB layout, and BOM.
Next I will post drawings on how to make wonderful and beautiful chassises. Using simple hand tools, with all the material being available at your local hardware. To most Americans, Mexicans, and Canadians. That would be Home Depot.
Take Care
Ivey
Praznik:
I am very glad to hear from You.
Yes the operational voltage was set at 30volts DC. But that was because we had limits that we had to stay within. Just in case that a portable unit was to be built in the future, it would not tax the submarines overall battery load.
Even today, in nuclear submarines, one of the most important items is the submarines battery load.
Why?
Inport, shorepower is used to startup the nuclear reactor. It uses thousands of kilowatts to bring it up.
At sea, if the sub must restart her nuclear systems. They will need every kilowatt they can get their hands on.
One thing that I need to put not there.
In the beginning, there was not too many transistors that were available.
But today, there are thousands. So you can use the excellent 2N4401, which is like a 2N2222A, with a lower max frequency and similar switching speeds.
I am posting the beautiful layout of the 2N2222A, with PCB layout, and BOM.
Next I will post drawings on how to make wonderful and beautiful chassises. Using simple hand tools, with all the material being available at your local hardware. To most Americans, Mexicans, and Canadians. That would be Home Depot.
Take Care
Ivey
Attachments
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Ivey, being that many of us are tinkerers, I promise to tinker on this circuit.
I was wondering about replacing the 15 uF electrolytics at input and output with film caps. Or at the least, paralleling a 10 uF and 4.7 uF Silmic caps on input and output. The Elna Silmic caps are highly regarded. I doubt you ran around looking for audio grade components when you put this together.
I was wondering about replacing the 15 uF electrolytics at input and output with film caps. Or at the least, paralleling a 10 uF and 4.7 uF Silmic caps on input and output. The Elna Silmic caps are highly regarded. I doubt you ran around looking for audio grade components when you put this together.
I already draw schematics and PCB in eagle and in one weak i will have the board. I will post pictures later. I still don't know which PSU to choose because the one that you post has output voltage 35 V, but i think that phono will work also with 35 VDC or no? Tell me also, what kind of transformer to use for PSU.
greetings
I still don't know which PSU to choose because the one that you post has output voltage 35 V, but i think that phono will work also with 35 VDC or no? Tell me also, what kind of transformer to use for PSU.greetings
Transformer for PSU
Praznik, you can use the following transformer, 120/220 ac volts @ 25 ac volts 1amp.
I have the following PCB software, CircuitMaker 2000 Pro and Standard, Protel 99SE and DXP Designer 2004; along with Eagle Professional 4.16.
They are complete and with license. I was issued them by employeers and the Soffware makers themselves. Plus I have my dos software, Autotrax and Protel Schematic for dos, including Orcad 3.10 for dos, along with Eagle 2.0 for dos.
I have moved away from using the complex software packages, because I no longer do production work. And the circuits that I do produce, does not require the bells and whistles that I once needed in the past.
I have been cutting my use down to QucikRoute 3.6 Pro and Express PCB, along with DIY Layout.
But if Eagle Lite works for you, by all means use it.
Take Care
Ivey
Praznik, you can use the following transformer, 120/220 ac volts @ 25 ac volts 1amp.
I have the following PCB software, CircuitMaker 2000 Pro and Standard, Protel 99SE and DXP Designer 2004; along with Eagle Professional 4.16.
They are complete and with license. I was issued them by employeers and the Soffware makers themselves. Plus I have my dos software, Autotrax and Protel Schematic for dos, including Orcad 3.10 for dos, along with Eagle 2.0 for dos.
I have moved away from using the complex software packages, because I no longer do production work. And the circuits that I do produce, does not require the bells and whistles that I once needed in the past.
I have been cutting my use down to QucikRoute 3.6 Pro and Express PCB, along with DIY Layout.
But if Eagle Lite works for you, by all means use it.
Take Care
Ivey
Gain
Gain is high, it was design to use the 1957 Electro-Voice cartridge at the time.
They put out high mv around 7.6-8.5 mv.
Modern phono cartridges, put out about 4.9-5.7 mv.
So your overall gain from this unit is on the realm of approx 1.25 volts.
Enough to drive most tube power amps that has 12AX7 preamps stages.
SS amps as well. But a line/tonal preamp is always a good idea.
An example is the Aikiko Mosfet Amp. It needs lot of gain to drive it to full output, so a preamp is desired.
Take Care
Ivey
Gain is high, it was design to use the 1957 Electro-Voice cartridge at the time.
They put out high mv around 7.6-8.5 mv.
Modern phono cartridges, put out about 4.9-5.7 mv.
So your overall gain from this unit is on the realm of approx 1.25 volts.
Enough to drive most tube power amps that has 12AX7 preamps stages.
SS amps as well. But a line/tonal preamp is always a good idea.
An example is the Aikiko Mosfet Amp. It needs lot of gain to drive it to full output, so a preamp is desired.
Take Care
Ivey
end of split.
Capacitors
When we first built the unit we used Sprague's Black Diamonds. That was 1959-60. They were really not that good, if you were to compare them today, with the capacitors from China or Taiwan. They were the new plastic type at 10%. If it was not for their size, we would have used oiled filled capacitors.
The new metal film capacitors today (across the board) are of good qualitly. Regardless as to who makes them.
But if you desire the use of MKP capacitors. Please use them and let me know what your results are.
Take Care
Ivey
When we first built the unit we used Sprague's Black Diamonds. That was 1959-60. They were really not that good, if you were to compare them today, with the capacitors from China or Taiwan. They were the new plastic type at 10%. If it was not for their size, we would have used oiled filled capacitors.
The new metal film capacitors today (across the board) are of good qualitly. Regardless as to who makes them.
But if you desire the use of MKP capacitors. Please use them and let me know what your results are.
Take Care
Ivey
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Steven:
Truly, there is no resistor on the base of Q2.
The 82k feedback resistor R6 and C4. provides base bias for Q2.
Putting a resistor on Q2's base may cause it to become unstable.
But go ahead, do some R & D, and let me know. Maybe with the more modern parts and materials. It may improve our old circuit.
Take Care
Ivey
Truly, there is no resistor on the base of Q2.
The 82k feedback resistor R6 and C4. provides base bias for Q2.
Putting a resistor on Q2's base may cause it to become unstable.
But go ahead, do some R & D, and let me know. Maybe with the more modern parts and materials. It may improve our old circuit.
Take Care
Ivey
Resistors:
Yes, we used the best carbon resistors available at the time. Dale, 5%.
There are people today who still enjoy the sound of carbon comp. resistors.
After years of study, about resistors. I still seek out carbon comp. resistors for three purposes. To use them in radio, power supplies and regulators. They are great in those roles. Because they do not add inductance or change the impedance of those circuits greatly. Some of my old friends, would not even give you one of their carbon comp. resistors. They have the old types, when making a good carbon comp. was an art form.
Some of the best carbon comp. resistors was used by Zenith and Muntz TV.
So if you get your hands on some of the old console TV's, you will have some good carbons. For they are far superior to what you can obtain today.
Take Care
Ivey
Yes, we used the best carbon resistors available at the time. Dale, 5%.
There are people today who still enjoy the sound of carbon comp. resistors.
After years of study, about resistors. I still seek out carbon comp. resistors for three purposes. To use them in radio, power supplies and regulators. They are great in those roles. Because they do not add inductance or change the impedance of those circuits greatly. Some of my old friends, would not even give you one of their carbon comp. resistors. They have the old types, when making a good carbon comp. was an art form.
Some of the best carbon comp. resistors was used by Zenith and Muntz TV.
So if you get your hands on some of the old console TV's, you will have some good carbons. For they are far superior to what you can obtain today.
Take Care
Ivey
This puts me in mind a little bit of the Dynaco PAT4 for some reason, probably because it used only 4 transistors a channel - 2 for line amp and 2 for phono preamp. It was something called a BC109 - I don't know how that would stack up to a 2n2222 sonically. I had one of those for a few years.
I once built a compact transistor phono preamp using MPSA18's selected for hfe's up around 1000. Initially I used only one transistor per channel and it sounded better than I expected, but a little low on gain, so I added a second gain stage using the same type transistor, and that's when the solid state grain really started to become noticeable to me.
I once built a compact transistor phono preamp using MPSA18's selected for hfe's up around 1000. Initially I used only one transistor per channel and it sounded better than I expected, but a little low on gain, so I added a second gain stage using the same type transistor, and that's when the solid state grain really started to become noticeable to me.
Thoriated:
What is "Fly over Country"?
Yes the BC-109, is an outstanding transistor in its own right. But I feel that the BC-107, is more useful.
One have to understand the history of transistor finance, in order to get an operational picture of transistor use and development.
It was cost that made designers, design as they did in those days. Transistors were new and expensive, compared to Tubes. A new 12AX7 would cost you 93 cent. You got two tubes in one. One 2N2222A, military grade, would cost $15.00 dollars.
When Motorola, discovered how to grow crystals cheaply, the prices dropped to a low of $4.00 dollars. But still, compared to tubes. It was expensive.
The db gain is all important in phono amps and in the use of transistors. A two transistor set up could give you as much as 35-40 db gain, depending on the transistor used. Looking at transistors with a hfe of 100-300 @
5v/2ma. You have a large range to chose from. And adding an emitter follower, enhances the current gain, that your will obtain and the lower impedance needed to drive capacitive loads and load matching.
With transistors costing 3-5 cents by the hundreds, It is only good practice to use general purpose transistors in your designs, when designing phono amps today.
The title "general purpose" is not what people think it is. An example of a general purpose transistor is the 2N3904. Some of its hfe gain spec's are off the chart at low amp transmission levels. Its power output is good over a given range, its noise level is a mere total 5 db. Plus it has good freq response and switching response.
When you use very high gain transistors. Your designing problems are increased, because you must design out all the unwanted noise, freq pick up, and a host of other ills that come with that type of transistor. And shielding. You may need to incorporate shielding.
The Pat-4 is a good preamp. I have the design of it. It was a good unit. And still is today.
Take Care
Ivey.
What is "Fly over Country"?
Yes the BC-109, is an outstanding transistor in its own right. But I feel that the BC-107, is more useful.
One have to understand the history of transistor finance, in order to get an operational picture of transistor use and development.
It was cost that made designers, design as they did in those days. Transistors were new and expensive, compared to Tubes. A new 12AX7 would cost you 93 cent. You got two tubes in one. One 2N2222A, military grade, would cost $15.00 dollars.
When Motorola, discovered how to grow crystals cheaply, the prices dropped to a low of $4.00 dollars. But still, compared to tubes. It was expensive.
The db gain is all important in phono amps and in the use of transistors. A two transistor set up could give you as much as 35-40 db gain, depending on the transistor used. Looking at transistors with a hfe of 100-300 @
5v/2ma. You have a large range to chose from. And adding an emitter follower, enhances the current gain, that your will obtain and the lower impedance needed to drive capacitive loads and load matching.
With transistors costing 3-5 cents by the hundreds, It is only good practice to use general purpose transistors in your designs, when designing phono amps today.
The title "general purpose" is not what people think it is. An example of a general purpose transistor is the 2N3904. Some of its hfe gain spec's are off the chart at low amp transmission levels. Its power output is good over a given range, its noise level is a mere total 5 db. Plus it has good freq response and switching response.
When you use very high gain transistors. Your designing problems are increased, because you must design out all the unwanted noise, freq pick up, and a host of other ills that come with that type of transistor. And shielding. You may need to incorporate shielding.
The Pat-4 is a good preamp. I have the design of it. It was a good unit. And still is today.
Take Care
Ivey.
Hi, Ivey -
'Flyover Country' is the part of the US that elite jet setters fly over when they travel between the east and west coasts
With the one stage phono preamp I made, the RIAA characteristic was obtained through feedback, so probably not the best equalization topology possible from a sound quality perspective. But I built it when I was still pretty young.
I didn't know that good small signal transistors were still that expensive in the mid sixties. Were germanium transistors as hard to design with for reliability as I have read?
'Flyover Country' is the part of the US that elite jet setters fly over when they travel between the east and west coasts
With the one stage phono preamp I made, the RIAA characteristic was obtained through feedback, so probably not the best equalization topology possible from a sound quality perspective. But I built it when I was still pretty young.
I didn't know that good small signal transistors were still that expensive in the mid sixties. Were germanium transistors as hard to design with for reliability as I have read?
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Thoriated:
No, Ge were easy, just like silicon. But they were heat sensitive. And they never made good power Ge. transistors, because of the heat issue.
To be honest about, Ge transistors have better tonal quality than most silicon units They are still being made, for use in guitar effects equipment. I built all of my grandsons guitar effect equipment. Now his friends are hounding at me.
No chance. Family yes, others no. I am retired, I just did not want my wife and daughter ganging up on me.
The 1960 saw the price of transistors fall. By the end of the 1960's transistor prices were down to about $1.00. But the of IC's was through the roof.
Take Care
Ivey
No, Ge were easy, just like silicon. But they were heat sensitive. And they never made good power Ge. transistors, because of the heat issue.
To be honest about, Ge transistors have better tonal quality than most silicon units They are still being made, for use in guitar effects equipment. I built all of my grandsons guitar effect equipment. Now his friends are hounding at me.
No chance. Family yes, others no. I am retired, I just did not want my wife and daughter ganging up on me.
The 1960 saw the price of transistors fall. By the end of the 1960's transistor prices were down to about $1.00. But the of IC's was through the roof.
Take Care
Ivey