My project "JLH-69"

Discussion in 'DIY' started by Zampotech, Feb 8, 2019.

  1. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    "JLH Germanium" part 1

    While powerful high-frequency transistors were on the road, I decided to try to build an amplifier on the powerful germanium low-frequency transistors P215.

    Here is on such a set of transistors:

    [​IMG]

    The P215 transistor is a powerful but very low frequency transistor. Its upper frequency is 10-12 kHz.

    We make a new PCB

    [​IMG]

    Prepare the radiators for the installation of transistors.

    The old transistors have mysterious pinouts on the body, so I had to work a little.

    [​IMG]


    Print and cut the template

    [​IMG]

    [​IMG]

    Attach the template to the radiators

    [​IMG]

    Drill

    [​IMG]

    Attach and prepare transistors

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    Solder one channel on the Board.

    [​IMG]



    Turn on and measure at different frequencies. The lower sine wave is the input signal


    At a frequency of 1 kHz:

    [​IMG]


    At a frequency of 10 kHz:

    [​IMG]

    At a frequency of 20 kHz:

    [​IMG]

    In all measurements, the quiescent current of the transistors was equal to 1 A

    Surprisingly, the JLH circuit made the transistor P215 work well at a frequency at which it should not work .

    In appearance, the sound of the sine wave amplifier on the transistor P215 is likely to be similar to the sound of a tube amplifier. But it should be checked for hearing.
     
    • Like / Agree Like / Agree x 16
    • Epic Epic x 1
    • List
  2. restrav3

    restrav3 Likes Audio-GD

    Contributor
    Joined:
    Jun 18, 2018
    Likes Received:
    128
    Trophy Points:
    43
    Location:
    PA
    That's a little too limited in frequency resposnse to be used a a stereo amp. Is it? In my experience, while about 15k is really not that essential between 10 and 15 there is a lot of info that is essential.
     
    • Like / Agree Like / Agree x 1
    • List
  3. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    "JLH Germanium" part 2

    Arrived transistors P605

    P605 transistor can work up to 30MHz

    New set of transistors

    [​IMG]



    Install on radiators and install on the PCB.

    [​IMG]

    Turn on and measure. The quiescent current of the transistors 0.65 A

    At a frequency of 1 kHz:

    [​IMG]

    At a frequency of 10 kHz:

    [​IMG]

    At a frequency of 20 kHz:

    [​IMG]



    Check on the meander. The square wave is a complex signal to the amplifier.

    At a frequency of 1 kHz:

    [​IMG]

    At a frequency of 10 kHz:

    [​IMG]


    At a frequency of 20 kHz:

    [​IMG]

    Transistor P605 has fully justified his appointment. The frequency response of the amplifier was remarkable.

    The working frequency band of this amplifier is similar to the original JLH.
     
    • Like / Agree Like / Agree x 17
    • List
    Last edited: Feb 22, 2019
  4. philipmorgan

    philipmorgan Member of the month

    Friend BWC
    Joined:
    Sep 28, 2015
    Likes Received:
    3,105
    Trophy Points:
    93
    Location:
    In the wind, so to speak (actually, Taos NM)
    Home Page:
    It's early, but one vote here for thread of the year
     
    • Like / Agree Like / Agree x 14
    • List
  5. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    You're right. Amplifier on transistor P215 was made only for experiment, as doll.. To debug the values of the elements.
    However, showed what works better than initially assumed.

    The operating range of the amplifier on the transistor P605 20...50000 Hz. Exactly the same as in the original JLH
     
    • Like / Agree Like / Agree x 2
    • List
    Last edited: Feb 22, 2019
  6. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    The design of the headphone amplifier on germanium transistors is similar to the design of the power amplifier.

    It is quite heavy, about 3 kg.
    Dimensions width 200 mm, height 120 mm, depth 180 mm.

    Germanium transistors require very good cooling, so I had to use large and efficient radiators

    The amplifier has no name yet. The working title of "JLH Ge605". If you could give me a name, I'd be very grateful.

    Approximate appearance

    [​IMG]

    A rough appearance without the top cover


    [​IMG]

    The shape of the case is made in retro style. The design was based on the project of radio station "the NORTH"

    [​IMG]



    The amplifier is now capable of delivering 2.2 W at 16 Ohms (sine wave). The power of the square wave signal is greater.
    The signal limitation at small overloads is soft. Like tube amps.

    This circuit is truly a masterpiece !!!
     
    • Like / Agree Like / Agree x 17
    • List
    Last edited: Feb 24, 2019
  7. AdvanTech

    AdvanTech Friend

    Friend
    Joined:
    May 13, 2016
    Likes Received:
    887
    Trophy Points:
    93
    Location:
    NYC
    Wonderful work! How about GeLH?
     
    • Like / Agree Like / Agree x 1
    • List
  8. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    Continuation. Photo essay on the manufacture of the case of JLH.

    I'll show you how to make a case for JLH. All photos I made with the permission of the shop Manager of the enterprise.

    Electronic model of the case

    [​IMG]

    [​IMG]

    Drawings in electronic form are transmitted to the laser cutting machine

    [​IMG]

    [​IMG]

    The result of the laser cutting machine

    [​IMG]

    Then the parts were transferred to the bending machine

    [​IMG]

    [​IMG]

    The result of the bending machine

    [​IMG]

    [​IMG]

    Now for me the most difficult task. Need to figure out a color for painting.


    I would also like to show a machine for punching shaped holes. He had replaced the laser cutting machine.

    [​IMG]

    This machine will soon be 90 years old. Alive, healthy, still working.
     
    • Like / Agree Like / Agree x 22
    • Epic Epic x 1
    • List
  9. Taverius

    Taverius Smells like sausages

    Friend
    Joined:
    Dec 27, 2017
    Likes Received:
    2,865
    Trophy Points:
    113
    Location:
    Rapallo, Italy
    ITT: Machinery Pornography.
     
    • Like / Agree Like / Agree x 6
    • List
  10. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    Big JLH already got the bones, but no meat yet. TCT5200 transistors have not arrived yet.

    That's what happened case.

    Bottom panel

    [​IMG]

    Bottom panel with front and rear panel

    [​IMG]


    Whole body

    [​IMG]

    While there is a pause, it is necessary to develop a logarithmic amplifier for VU meter (Power output indicators)
    Standard schemes work ugly. Arrow VU meter frantically jump on the scale.
     
    • Like / Agree Like / Agree x 8
    • List
  11. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    Big apologies to everyone watching this topic. The delay in the update.

    Two problems arose.
    The first is the long delivery of VU meter.
    The second - I chose the wrong varnish for the front panel.
    I had to redo everything.

    The first two amplifiers. The front panel is made in the color "dark walnut" and "light walnut"

    [​IMG]

    [​IMG]

    I think the dark amplifier looks much more beautiful.
     
    • Like / Agree Like / Agree x 23
    • Epic Epic x 1
    • List
  12. restrav3

    restrav3 Likes Audio-GD

    Contributor
    Joined:
    Jun 18, 2018
    Likes Received:
    128
    Trophy Points:
    43
    Location:
    PA
    this is a thing of beauty. both colors look good to me. the metal work up there in your previous post is mighty impressive.

    will look so good next to my ginclones
    modern next to oldie but goodie kinda theme

    [​IMG]
     
    • Like / Agree Like / Agree x 1
    • List
    Last edited: May 3, 2019
  13. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    While working on this project, another task was solved.
    It was necessary to produce a sane power output indicator without the use of cumbersome and complex solutions.
    The purpose of this power output indicator is to show power in proportion to the perceived audio power.

    Human hearing has a logarithmic characteristic of the sound volume, so the arrow VU-meter should deviate according to the logarithmic law.


    I did not like the work of conventional power indicator schemes. I had to strain my head


    For this purpose, a quasi-logarithmic amplifier was created from simple and accessible elements.

    [​IMG]

    It is made from a chip for hearing AIDS. The result is a quasi-logarithmic amplifier-detector.

    The amplitude characteristic is shown in the graph.

    [​IMG]

    The horizontal axis of the AC input voltage (mV). The vertical axis is the DC voltage at the output (V)

    Additionally, boost elements have been added that allow the counter arrow to cheerfully show power and not sluggishly move like a drunk lady.

    Here's what the finished design looks like on a VU meter

    [​IMG]

    [​IMG]

    Analogues of this scheme I have not found, so the priority will probably be mine :punk:

    The circuit is working, can be adapted for other VU meter. You can use it in your designs. On questions to be sure answer
     
    • Like / Agree Like / Agree x 17
    • Epic Epic x 2
    • List
    Last edited: Jun 4, 2019
  14. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    Finally I almost finished this project

    During the work on this project, there were two variants of the power supply unit, 5 different printed circuit boards were manufactured.
    Two options of sound power indicator, three options of printed circuit boards.
    The amplifier circuit was not changed, but 7 variants of printed circuit boards were manufactured.

    Third or fourth version of the amplifier module

    [​IMG]

    Seventh version of the amplifier module

    [​IMG]

    "striving for the better is the enemy of the good" :mad:

    The result on the photo:

    [​IMG]

    [​IMG]

    The wires are not fixed yet. So there is some mess.



    [​IMG]



    The amplifier received its own name "MAGISTER". as a sign of respect for the talented engineer J. L. Hood

    For testing, the equipment of the DOCTORHEAD store was used

    [​IMG]

    [​IMG]

    [​IMG]

    I bring great gratitude to the staff of this store.

    The result of the amplifier is close to the expected.

    @purr1n was absolutely right when he predicted the excellent performance of this amp in bass.
    The bass of this amplifier is great. The bass is bright , like the sound of a cowboy whip. Even the spinal cord can hear.

    Will soon do a video of this amp on their speakers.

    Video of the amplifier in the store unfortunately recorded without sound:(
     
    • Like / Agree Like / Agree x 23
    • Epic Epic x 1
    • List
    Last edited: Jun 14, 2019
  15. mdr30

    mdr30 Rando

    Joined:
    Apr 4, 2016
    Likes Received:
    21
    Trophy Points:
    8
    Is the headphone version coming along?
     
  16. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:

    Yes, certainly. It'll be on germanium transistors. The amplifier is already there, but it doesn't have a case yet.
     
    • Like / Agree Like / Agree x 5
    • List
  17. Gazny

    Gazny Almost "Made"

    Contributor
    Joined:
    May 11, 2020
    Likes Received:
    548
    Trophy Points:
    93
    Location:
    SoCal
    Great work should not be forgotten. Found your great work from many days of reading on the form. This amp should not be forgotten. Germanium and VU meters oh my. I much rather support a great community member than untested units on ebay. Hope to see more great work @Zampotech .
     
    • Like / Agree Like / Agree x 1
    • List
  18. batriq

    batriq Probably has made you smarter

    Friend
    Joined:
    Oct 31, 2015
    Likes Received:
    891
    Trophy Points:
    93
    @Zampotech Are you planning on selling some units? :)
     
    • Like / Agree Like / Agree x 3
    • List
  19. Zampotech

    Zampotech Friend

    Friend
    Joined:
    Oct 15, 2018
    Likes Received:
    3,450
    Trophy Points:
    93
    Location:
    Moskou
    Home Page:
    Yes, of course. I have already purchased a VU meter

    [​IMG]

    Original TOSHIBA transistors

    [​IMG]

    And some radiators for the headphone amplifier on germanium transistors.

    [​IMG]

    I want to increase the cooling area of the radiators for the power amplifier. During operation, the radiators areheated to about 60 degrees Celsius. For transistors, this is not terrible, but it is uncomfortable to touch with your hands.
     
    • Like / Agree Like / Agree x 19
    • List
  20. batriq

    batriq Probably has made you smarter

    Friend
    Joined:
    Oct 31, 2015
    Likes Received:
    891
    Trophy Points:
    93
    That is awesome! Sign me up!
     
    • Like / Agree Like / Agree x 4
    • Miss Information Miss Information x 1
    • List

Share This Page