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Getting G3 Whisper Perch USB working
Posted by: croissantking on 2023-03-22 19:59:14 Do you have a powered USB hub you could try between the devices you test and the Mac? No, I don't have one. Would this be helpful, what's your thinking?
Posted by: Fizzbinn on 2023-03-22 20:04:05 No, I don't have one. Would this be helpful, what's your thinking? If a problem is suspected with device power draw (a perch card USB power output issue) having a powered USB hub would mean hub connected devices would would not pull USB power from the perch card USB port (instead from the hub's power supply). Might validate the data/signaling portion of your work is right?
Posted by: croissantking on 2023-03-22 20:13:20 If a problem is suspected with device power draw (a perch card power output issue) having a powered USB hub would mean hub connected devices would would not pull USB power from the perch card USB port (instead from the hub's power supply). Might validate the data/signaling portion of your work is right? Just ordered one off eBay 🙂
Posted by: Fizzbinn on 2023-03-22 20:31:10 Just ordered one off eBay 🙂 Fingers crossed it helps with debugging!
Posted by: Phipli on 2023-03-23 02:09:50 It will help hugely, but the issue is the wrong component (mostly caps) values fitted rather than the design of the Perch card. What current is the fuse you fitted?
Posted by: croissantking on 2023-03-23 03:56:29 It will help hugely, but the issue is the wrong component (mostly caps) values fitted rather than the design of the Perch card. What current is the fuse you fitted?
Posted by: croissantking on 2023-03-23 09:28:12 I’m waiting on a few things to arrive: - SMD oscillator - Component tester - Polyfuse similar to the 30R090 - Powered hub
Posted by: croissantking on 2023-03-24 18:53:24 New oscillator and polyfuse fitted tonight. Looks tidier. I removed the diode at D2, since I don’t know what value it should be, which way round it should go or if it’s actually needed. The card seems to operate the same without it. Maybe a thyristor goes there.
Posted by: mg.man on 2023-03-25 05:33:20 Awesome progress so far!! In case you're after one - https://www.ebay.co.uk/itm/125843022879
Posted by: croissantking on 2023-03-25 05:53:37 Scanner now working, USB CF card reader now working. I removed C146 and C144 (incorrectly labelled C2 on my schematic).
Posted by: croissantking on 2023-03-25 08:27:51 Dremel duty done ✅
Posted by: croissantking on 2023-03-25 08:34:57 With the backplate fitted it seems to be the case that plugging in the previously offending hard drives no longer results in sudden restarts. I need to do more testing before I can say this is fully working, but it certainly seems pretty damn functional. Anyone else going to have a go? There’s also the soft power circuit to look at if anyone’s keen.
Posted by: Phipli on 2023-03-25 08:55:06 Anyone else going to have a go? There’s also the soft power circuit to look at if anyone’s keen. Have you tried to see what happens if you press the power button on a USB keyboard that has one?
Posted by: croissantking on 2023-03-25 08:59:55 Have you tried to see what happens if you press the power button on a USB keyboard that has one? Yes — nothing.
Posted by: just.in.time on 2023-03-25 11:33:30 I’m interested in trying this! I was looking at the cards I have (one installed, 1 backup), both are the AV variant. However, after looking close they are completely different layouts. One appears to have the space for the USB controller chip, the other doesn’t. I’ll get some photos and part numbers uploaded here later today.
Posted by: mg.man on 2023-03-25 12:36:16 Anyone else going to have a go? Definitely tempted!! Do you have a cheat sheet with everything that's needed? 😀
Posted by: mg.man on 2023-03-25 12:37:56 ...and would you entertain providing an "upgrade" service? 🙂
Posted by: croissantking on 2023-03-25 13:22:41 @Phipli what are your thoughts on the choice of capacitors surrounding the USB chip?
Posted by: croissantking on 2023-03-25 13:25:57 Definitely tempted!! Do you have a cheat sheet with everything that's needed? 😀 Yes - the last version of the schematic I posted on here, on page 10 I think, but it needs updating again. I could put together a Mouser BOM for anyone interested. ...and would you entertain providing an "upgrade" service? 🙂 Yes, sure, we could work out a deal on this.
Posted by: mg.man on 2023-03-25 13:52:17 Yes, sure, we could work out a deal Cool, will drop you a PM.
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