Build Finished - HiHat Decay not working [SOLVED]

Discuss Nava construction and related issues
  • S7 not working is most likely due to a broken trace as well. Check traces around S7. Volume differences are software related. I find that there is yet no version available with overall balanced instrument volumes. That Hihat sounds really distorted as well. Check for tiny solder bridges at the RA9x resistors. Also try swapping IC67. Maybe post some high resolution pics as well...
  • I found the broken trace on IC Pin5 to the via. Haven't tested yet...

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    Continuity between IC112 pin1 and R447 and D196,197 junction is GOOD.

    What else could be the hihat decay problem?

    Distorted? I didn't notice that. I have no spare M5218L Mitsubishi's...

    No solder bridges/continuity between the RA9x's (Except the trace where they are all connected). All the RA9x's are connected/continuity to where they are supposed to on IC68.

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    Thanks!

    EDIT>>>

    Selecting Open HiHat (Which I didn't do yesterday). VR23 (Open HiHat Decay) does NOT work.

    Tried swapping out IC68. No change.

    So in summary. Open and Closed HiHat decay does't work.
  • Did you solder the ground of the pots in the HH section from the top? Can't see any solder applied to the pads...
  • Soldered all VR's from the top (after cleaning bottom).
  • hofmann25 wrote:Soldered all VR's from the top (after cleaning bottom).
    Maybe you should check all the traces in the HH section as well. Wouldn't be surprised if you find one more. I had a Nava for repair a while ago which also had malfunctioning instruments due to broken traces:

    http://e-licktronic.com/forum/viewtopic.php?f=24&t=1099

    I also experienced quite a few defective 2SA798 transistors in the kits. You can replace them like this if you don't have the original part:

    http://e-licktronic.com/forum/viewtopic ... 7429#p7429
  • Thanks KG, yeah I'm pretty much exactly on that trail. Almost finished checking all traces. Failing that I'll try replacing that double tranny, although I tested it before placing. Mind you I have tested ALL the parts before placing.

    Soooo easy to break traces and via's....
  • Checked continuity will all components in the HiHat section. All connected!

    :idea: :arrow: Are pins 3-7 not used on IC70?

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    I have checked ALL Components during build except IC's. I'm wondering if it's worth pulling Q84 as I checked it before placing...

    Might try replacing the IC's first???

    As I can see Q72, Q73, C135, R451, VR21, R452 & VR23 seem to be responsible for the Decay of OH & CH...

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    But it's unlikely that ALL of these would be fucked. And there is NO IC in this area of the circuit so I'm at a loss of what could be wrong... :roll:

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    :cry: :cry: :cry:
  • I changed out ALL the IC's & I replaced the 2SA798 with 2x matched BC577's and there is no change! :evil: :x

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    What could this be??? :cry: :cry: :cry:
  • Try swapping IC111 and IC112. Otherwise I run out of ideas... :?