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Sorry for the mistakes!
Oof! There was a resistor that was only half soldered!Hey there!
Doing the calibration on my Rev D and everything was going well (except for realizing it was in smash mode half way through and needing to restart), until I hit that GR off switch. The LEDs went nuts and if I unmuted the tone would come in quickly and seemingly randomly. When I switch it back in the output LEDs slowly settle but on the GR side the slam LED stays lit. As I wait for my next day off, is there any area that I should be looking to? An IC issue, perhaps?
Here's a little video of the issue: FET 500 Rev D Help
And some pictures too.View attachment 94743View attachment 94744View attachment 94745View attachment 94746
Just going to add: this gain reduction issue is so weird. The input know acts as an oscillator for the intermittent signal. Low input=slow, high input=fast. I'll try to look some more but I think I might be sending it in.Oof! There was a resistor that was only half soldered!
I reflowed everything, and am waiting for an extender in the mail. Hopefully this time if it messes up I'll be able to diagnose the issue.
Quick question re: resistor tolerances. I am building a Revision A FET/500. While sorting resistors, I found that my 10M Ohm carbon resistor (R45) was coming in at just above 11M ohm. From my understanding, the gold band indicates a tolerance of +- 5%. So this is measuring around a 10% tolerance range. I know my meter could be the culprit, but I am able to measure the 15M ohm resistors without any issues.
Is this result indicating a bad resistor? Or is this falling within an acceptable range for this circuit? Additionally, if I need to replace it, will any standard 1/4 watt carbon film 10M ohm resistor fit the bill? Or are there specific brands/specs that are the best fit for this use case?
Not sure if the powers that be are following this thread anymore. Mike from Haiball has been very attentive to messages on the web site.Quick question re: resistor tolerances. I am building a Revision A FET/500. While sorting resistors, I found that my 10M Ohm carbon resistor (R45) was coming in at just above 11M ohm. From my understanding, the gold band indicates a tolerance of +- 5%. So this is measuring around a 10% tolerance range. I know my meter could be the culprit, but I am able to measure the 15M ohm resistors without any issues.
Is this result indicating a bad resistor? Or is this falling within an acceptable range for this circuit? Additionally, if I need to replace it, will any standard 1/4 watt carbon film 10M ohm resistor fit the bill? Or are there specific brands/specs that are the best fit for this use case?
Thanks in advance for the help, appreciate all the hard work put into these kits!
Thanks @mrmike186! I actually contacted them through the website right around the same time I made that post. For folks who run into a similar issue, the basic gist is that:Not sure if the powers that be are following this thread anymore. Mike from Hairball has been very attentive to messages on the website.
Is it possible that the issue is with the card connector on the actual rack? Since it doesn't occur when using the extender cable, I could see a situation where the 500 module causes the rack's PCB to flex a bit under the weight, which may cause a bad contact to go in or out. Since the extender plug is super light, it may not impact the rack's connector at all. Apologies if you already investigated this possibility. Good luck!I have a frustrating issue on my REV A unit. I get a nasty, high frequency distortion (nothing pleasing, an almost digital clipping sound), on peaks occasionally. The bad part is, when I pull the unit out of the rack and use a 500 extender cable, the problem goes away. I think the problem occurs when pressure is put on the front panel. I can go for weeks without problems, and then the problem reappears. If I repeatedly re-seat the module in the chassis, the problem eventually will go away when I get things just right.
Again, I can't make the problem appear when out of the rack. I've tried re-flowing some of the solder joints, but haven't had any luck.
Any tips on how to troubleshoot this issue?
Thanks for your response. I've tried it in multiple 500 series racks, and have gotten the same results.Is it possible that the issue is with the card connector on the actual rack? Since it doesn't occur when using the extender cable, I could see a situation where the 500 module causes the rack's PCB to flex a bit under the weight, which may cause a bad contact to go in or out. Since the extender plug is super light, it may not impact the rack's connector at all. Apologies if you already investigated this possibility. Good luck!
Bummer, sorry to hear that. Wish I could offer more help!Thanks for your response. I've tried it in multiple 500 series racks, and have gotten the same results.
Maybe there is something written somewhere that I am not seeing, but I am curious about the resistor spot labeled "r-opt" not shown on the BOM.
I'm working on the Rev D like pictured at the top of the page. Though it's blocked mostly, you can see the place I'm talking about on the top left of the pcb.
I'm assuming it's an optional resistor and the leftover 3.9M resistor I have goes there, but what does it do?
Ah, thank you. I knew it was something interesting. I am curious about comparing Revision A in the future.
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