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Mikorist

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  1. heheh - da li Dr. Zen moze da osmisli shemu Babelfisha sa 2 jFeta u izlazu :buehehe:i u ulazu i u izlazu jFetovi - jel to moguce ?
  2. zaboravite na celu pricu - u medjuvremenu sam sklopio Babela - no mozda je neko shvatio poentu ....
  3. ovaj post je od 16 oktobra 2009 ----- > videti sadasnji "aktuelni" : http://www.diyaudio....dpost__p__35333
  4. Zaopoceta je ova ista tema ovde : http://www.diyaudio....lone-amplifier/ josh - 16 Oktobra 2009 .... (sad je 30 Aprili 2010) i umesto kita dobio sam kitu tad ... kome nije jasno sta se dogadja ovde i sad - nema veze ... u medjuvremenu sam sklopio Babela - no mozda je neko shvatio poentu ....
  5. ovakve:http://www.diyaudio.rs/topic/1718-apex-i-gc/page__view__findpost__p__35153
  6. trazim kit a ne kitu http://www.chipamp.com/lm3886.shtml
  7. moze li neko da mi nadje ili napravi ove plocice - bas sam se naprzio da pravim
  8. Mikorist

    Photobucket download ?

    ne bi trebalo da mozes ako ne dozvolis kroz opcije tamo - odnosno da bude public album... u ostalom probaj:http://i75.photobucket.com/albums/i306/mikorist/
  9. Ja to ne znam - a i svejedno je bezveze izvuci listing firmi i staviti to na forum - bas me briga i za g. Mileta i za poslovanje firme "Apex" - to nije temaovog foruma.... sem ako se ne reklamiraju na mestu na Forumu predvidjenom za to...nikom se nista nije dogodilo a i nece - samo sam u afektu prebacio postove gde im je mesto a ako Zen smatra da nije valjanomogu se i vratiti...ovo nije forum gde se peva pesma : Ban ban -bannecu nista da znamBan-ban-bannecu nista da znamBan-ban-ban-ban-bannecu nista da znamnisi dovoljno brzBan-ban-banSve vas vidi sve vas vidi internet policija svetlost univerzuma internet policija jahaci hifi foruma.
  10. deo teme o ispitivanju firme itd... odvojeno je gde joj je mesto .... http://www.diyaudio....__0entry35294 mislim sta reci a ne zaplakati....
  11. mozes li u ovu da udjes ili vecu da nabavljamo ?
  12. ako je tako onda i meni da sklopish jedan
  13. sta znaci "vrh" = najbolje ?
  14. eto jednog specijalnog visokonaponskog prekidaca
  15. e ovo je to sto mi treba - samo fali i klonja u istom modelu
  16. ako se racunaju bio jonizatori - zujalice i ostalo iz male skole elektonike radio kluba i ja se bavim elektronikom preko 25 godina
  17. Mikorist

    APEX i GC

    a ima i josh jedna tema ovde :http://www.diyaudio.rs/topic/446-gain-clone-amplifier/page__view__findpost__p__21490
  18. Mikorist

    APEX i GC

    da ne kaze neko da trujemo samo sa pass pojacalima posle... Analysis of the pictures of the Gaincard innards by Mick Feuerbacher, October 2005. In 2002 in a thread in Audio Asylum some pictures were presented that were said to show the inside of an original Gaincard. Shortly thereafter Yoshi Segoshi of Sakura Systems responded, claiming that the photos were not of a 47 Labs Gaincard and when asked to provide photos of the internals of a real Gaincard, he refused to do so. Recently, some new images occurred in a 6moons review of the Gaincard. These images showed a very similar board with similar looking components and soldering style, similar cables and connectors and a similar stepped attenuator. These pictures were officially provided by the manufacturer. Comparing the old images with the new ones, I am now quite convinced that the images shown on Audio Asylum were showing the inside of the real Gaincard. I carefully analyzed them in order to deduce the parts and schematic used for the original Gaincard. Most probably this has been done by millions of DIYers out there before, but I could not find the information in the internet. Maybe my findings are interesting for others as well, so I present them here. I am open for discussions, of course. If you don't agree with my conclusions or want to add something, please contact me (m at dogbreath dot de) .... The first of the images appearing in the Audio Asylum thread. It was said that the pictures were taken by Craig Fraser. I hope he does not mind that I use them here. This is the top side of the board with the two skinned supply bypassing caps. On the bottom of the picture the 12 position stepped attenuator with the green switch is seen. The second image, showing the bottom side of the board. Rectified image with the connectors labelled. The chip is a national LM3875. O: output; +: pos input; -: neg input; V+ and V-: pos and neg supply; n: not connected. Bottom of the PCB with connectors labelled. In green are shown the locations (and connections) of the parts located on the front of the board. The non-connected pins are cut off, only pin 11 (left) was left in order to fix the chip and make a connection to V-. There must be a bridge from pin 11 to pin 4 (V-) under the chip. The Resistor on the top side of the board (previous image) goes through a hole at the position of pin 3 and is bent to connect to the negative input. There is only one ground on the board, the copper area in the front of the image. No separation of power and signal ground is made. By careful inspection of the images I have deduced the schematic used. It is a non-inverted rather minimalistic approach. The number of parts, excluding the attenuator and R0, is nine as claimed by the manufacturer. Although the design is non-inverted, a DC blocker cap is used at the input. I am surprised to see that they used an electrolytic here. Resistor R0 extends the range of volume control by one step (Thanks Stabist!). This is on the cost of the fully attenuated position. You have to use mute switch for total silence. A Zobel network is used on the output. The switch is not a power switch. It simply disconnects the output from the speakers. What is what on the pictures... The labels shown are identical to those used in the schematic above. Indeed, if you scale the image and calculate the length of the signal path (if you do not include the Zobel and Rg) you arrive at something close to 32 mm, as 47 labs claims for the Gaincard. The values of the resistors are: Rg: 22k, Rf: 22k, Ri: 680. The gain is 33. All resistors seem to be carbon film types. Tolerance is 5 %. There is no way to identify R0 or the capacitor values. At least, we can determine the dimensions of the components. The Cs caps have a diameter of 15 mm, Ci of 5.4 mm, the dimensions of Cz are 2.6 mm x 7.5 mm. Judging by the color, they may have used a WIMA 100 nF polyester cap for Cz. 100 nF is the value specified in the LM3886 datasheet and the WIMA measures 2.5 mm x 7.2 mm, which fits very well. Maybe someone can identify the makes of the other caps according to their size (let me know if you do). The value of the Cs caps is 1000 uF for the 25 + 25 W version and 2200 uF for the 50 + 50 W version. The PSU (Power Humpty) This information was collected from other sources in the internet. The Power Humpty contains a high quality non-toroidal 170 VA transformer. Secondaries are 23.5V, 3.6 A. There are only four diodes, used for the positive and negative rails. The diodes are FE5D 9808 (General Semiconductors). There are no capacitors in the Power Humpty. The ground connections of the positive and negative rail are separately led to the amp boards. FROM: http://dogbreath.de/...d/GainCard.html Next is a best-guess schematic showing a possible physical layout. Grounding is critical. The chips should be well heatsinked, but electrically isolated from the heatsink. An isolated version of the LM3875 exists which makes this easy to do. Both channels should be mounted on the same heatsink if possible. R1 ** R2 22k R3 680R R4 22k R5 1R C2 4.7 µF / 50V Black Gate N series C5 0.22 µF / 63V WIMA MKS C6 1000 µF / 35V United Chemicon LXV or similar C7 1000 µF / 35V United Chemicon LXV or similar U1 LM3875T ** 12 step ladder attenuator, use 22k, 4k7, 2k2, 1k5, 1k, 680R, 470R, 330R, 220R, 150R, 68R, 33R. A 50 kOhm volume potentiometer could be substituted. Junji Kimura
  19. Mikorist

    APEX i GC

    Stvar ukusa :cheers:ovde je bio ceo forum posvecen ovome :http://web.archive.o...om/ffakeidsfrm1
  20. Mikorist

    APEX i GC

    Takodje iz webarhive: http://web.archive.o...dio/diy_gc.html sta da radim kad volem GC
  21. Mikorist

    APEX i GC

    ovde se moze naci prvi text napisan o GC (2002 godina) : http://web.archive.org/web/20021208152635/home.ca.inter.net/~cfraser/Gainclonehome.htm sajt ne postoji ali ima ga u webarhivi
  22. Mikorist

    APEX i GC

    http://www.diotec-usa.com/RECURV.htm http://www.diotec-usa.com/GUIDE2.html a imaju i Hyperfast
  23. Mikorist

    APEX i GC

    Ja sam se ovde ucio na Schottky diodama - no ove MUR860 su super brze diode - no ima manijaka koji koristei ULTRA brze...
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