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ttb

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  1. Haha, of course I guess the only real reason to build one is if you want it to be long and/or thicker gauge.
  2. The standard ATX extension works great until you have to deal with one of the socketed logic boards. They have a capacitor next to the power connector that blocks the overhanging part of the connector. Unless folks have figured out a clever workaround I’m not aware of. For crimping the pins, I used an Engineer PA-20. It doesn’t do a good job with the strain relief crimp but made perfect crimps on the conductors. Since you’re in Japan @JDW I imagine you can find one for not too much.
  3. Based on how jumbled those analog board capacitors are and the fact that they all appear to have a black marker dot on them I'd guess the analog board has already been recapped as well, but I usually mark them before removing them for recap so maybe someone was going to start the process and was interrupted. Are there any without the dot? If you turn the computer on without the logic board in does the fan run and power light come on? If it does, you can then insert the logic board to "jump start" it by bypassing the EGRET chip that initiates the power on cycle. This isn't recommend
  4. What a thorough video, amazing. I can't be sure, but I believe that the Console 5 kits you mention at 48:00 likely include both the solid tantalum caps and Nichicon VX axial caps, hence their description. Someone who's actually bought the kit can chime in, though.
  5. Edit: Now I see the OP hasn't replied for almost a year. Hope you've already figured it out! Are you saying the three middle pins closest to us in the second photo are not connected to the three vias because the little section of trace from the pad was obliterated? Just cut some short lengths of magnet wire and solder straight from the pin to the via. Clean off that flux, too. For the first board, the easiest is just to superglue the caps down where they should be (very small drop) and then run thin wire to the closest pin it would normally connect to. If you really wan
  6. Very interesting. Your peak voltage is similar to mine, but the your minimum appears to be much lower, resulting in the large p-p measurement. I believe that may be because you are pressing the interrupt switch repeatedly (e.g. from a sad Mac). The first signal captured by your scope is therefore the single chord of the sad Mac chime rather than just the ascending tones which is what my wave forms are. For my testing I always hit the reset switch, armed the scope, then hit the interrupt switch to only capture the ascending tones @aeberbach spoke of. My guess is that if you do the tes
  7. Alright, these measurements are from my other SE/30, recapped with the same caps. All are waveforms of the ascending tones played when the interrupt switch is pressed. I changed the system volume to 7/7 before testing. Note: These are all with respect to ground. I also measured across the components directly and the signals were substantially similar. C3 sees a max of 8.56 V: C4 sees a max of 8.67 V: C5 is a constant 5 V (plus a fair amount of noise): C6 is a constant 1 V or so:
  8. That should be even easier. To clarify, we're talking about probing C3, C4, and C5 voltages while playing the ascending tones?
  9. I'm just here to say that your desk/chair combination is a perfect match for the SE/30, great looking setup!
  10. If I have a couple hours this week I will open it back up and probe the rest of the circuit while playing the tone to provide the full picture. I'd imagine there is some difference from the fact that @aeberbach was playing a different sound, but that can't explain all of it.
  11. I measured that 5.81 V p-p at the internal speaker header with the speaker connected. The measurement setup was the scope probe on the positive pin on the back side of J11 with the ground clip attached to a rear connector housing. The previous measurement I quoted was at the external headphone jack on the same computer with the same sound file. In that case, there was no load present, though, so they aren't necessarily comparable. So this test could address your second stated goal if someone else repeats it with different capacitors and we ignore the part-to-part variation in stock
  12. Alright, unfortunately I have bad news. The SE/30 with solid tantalum caps is my non-working unit, so I am unable to get the comparisons. My two functional SE/30s both have polymer tantalum capacitors. I did, however, measure the 1kHz waveform at the speaker jack (with the speaker plugged in). This is what that looks like on max volume (7/7): 5.81 V peak-to-peak. It is really quite loud, qualitatively. If someone has an SE/30 with solid tantalum capacitors or better yet aluminum electrolytic, they can use the sound file I linked above and repeat this test so we can com
  13. Absolutely, I plan on measuring my other board this week when I have time to do the swap. The purpose of the test above was to provide a way for anyone to compare sound output levels objectively. I'm also concerned that the difference between polymer and solid tantalum caps will be so small that it won't be audible. Also, note that although the ESR of the polymer caps is much lower, the impedance is not that much different in the audio frequencies, at least according to this chart: I'll leave it to an actual electrical engineer to opine on whether that mat
  14. Alright, I haven't done both SE/30s yet as my solid tantalum system is awaiting a new HD right now, but here are some preliminary results and methodology so you guys can hopefully compare. Test method: I generated a 1kHz sine tone with Sound Edit 16. It's 10 seconds long and has an 80% amplitude. I saved this as a System 7 sound, attached to this post (stuffed with Stuffit 1.5). I set the system volume to maximum. I connected a Hosa 3.5mm TRS to 2x 1/4" TS adapter cable to the computer's audio output port. I connected a multimeter to the left channel's T
  15. This is the cart I use whenever I order a set of SE/30 logic board caps: https://www.digikey.com/short/z134vr The specific part is this: T521V476M020ATE090 KEMET | Capacitors | DigiKey I'm using KEMET 20V poly tant caps for all of the 47 uF parts. Nominally its a "low ESR" part with a 90mOhm ESR at 100kHz. KEMET specifies a 20% derating for specified voltages over 10 V, which these are. That means 16 V which would still give some headroom per @JDW's concern and @aeberbach's measurement. Note that they allow for no derating for transients, as well. I didn't
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