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"The speakers ARE the room treatment."

I removed the positive reg and discovered it still worked on my bench supply. Soldering the pins onto these is getting harder for me, and I think one of the solder joints on this one was bad and disconnected when I had the amp running the other day. I think I may have lifted a pad, so will probably order another reg and figure out a better way to hold the reg and the pin(s) when soldering. These things are small. I hooked my amp up to the bench supply just to confirm the currents I was seeing and it was in range. Mine was actually higher at 330/320mA +/-, but mine is built using MPSW thru hole transistors with creative lead bending.

Let me connect the fax.

Hope that new dead ones is still salvageable TI TPSA7A4701 would oscillate under some extreme circumstance but most likely that's not the case especially you have electrolytic caps installed. I would go back to experiment with thermal like force air flow on regs to see if the problem is solve then thinkering with passive setup.

@blessingx

If Stayin' Alive Had Been Written in the 16th Century

Lens-DB.com closing down. https://lens-db.com/blog/website-closure/ I rebuilt lens-db.com from its ashes: introducing The Lens DB. https://thelensdb.com/

The original reg did not work using my bench supply. The new reg (the now dead one) worked fine off my bench supply, but I haven't removed it yet since it went bad. The data sheet notes that these are supposed to go into protection when stressed. I presume that once they go into protection, they are supposed to come out of it once things settle down without the user having to do anything. I've never been around when the bad stuff has been happening. This time, I left the amp running on the bench (no signal), and when I returned, it had failed. Do Amb's regs have a reputation for oscillating? In this amp, the electolytic caps are Elna Silmic IIs, which I presume are not low ESR (the owner mandated these). I'll poke around Amb's forum and see if anyone noted oscillation.

did the old regs still working individually after removed from mini dynalo? 4V difference looks fine even a bit too much for amb σ78/79 , I would check the DC voltage ,also check output waveform on scope to see if it's oscillating when symptom occurs

Question time: One of the people I built a mini dynalo for sent it back to me for repair. They apparently had something stacked on top of it with it on for a day. When they turned it on the next day, no workee. When I got it, the first thing I noticed as only 2 of the 4 pcb leds were on, and sure enough, the positive reg (amb) had bit it. I went ahead and removed that and ordered another reg. While waiting for that, I powered it using my bench supply and didn't find anything wrong that I could find. DC offset was fine, bias was fine. Did a diode test on all of the output transistors with no problem. When the replacement reg got here, I went ahead and put it in after seeing no issues on the bench supply, and it turned on fine. This weekend, I was going to get it finished up to return the amp, and went ahead and let it run for an hour or so with the heatsinks on, but much of the case missing. When I went back down to check on it, the offset was around -900mV and then I noticed that 2 of the leds were off. Positive reg bit it again. I went down tonight and measured the +/- rail currents at +288mA and -278mA after running for quite awhile on the bench supply. These regs are supposed to handle up to 1A each, and have thermal protection. I took a heat gun and noticed the current was going up pretty fast when I was heating the output section; up to over 350mA after a short time and climbing. I did not wait to see how far it might go. I have no idea how hot one of these could get with something sitting on top of it, but I'm guessing quite hot. I know the regs current capability will vary with heat and how much voltage they are dropping, which in the case of these is 4V(24V in, 20V out). I'm injecting the bench power on the electrolytic 100uf caps. There are (4) 100uf tantalum polymer caps following the electros, which may not like heat much? I don't know. Amb's regs are up to $30 ea. with $10 shipping, so I don't want to keep burning these up. Just looking for ideas on where to look next?

Egad, that's chilling. He is so full of himself, he actually believes he's righteous, he actually believes he can decide the fate of the lives of millions, if not billions. "...we might as well get it over with..." == "...final solution..." of Nazi Germany.

https://www.reddit.com/r/AskSocialists/s/xq7xBxW7JH Also https://www.bbc.com/news/articles/ckg8wvz427vo

Among the foundational texts of Stretchosity.

Added lights to the patio. Previously Now with lights That work! And are automated!

It was my first gumbo. I’m pretty happy with it.

That looks yummy!

Making a chicken filé gumbo

Breakfast at the Mayberry compound. I made homemade biscuits while Al manned the flattop. He cooked bacon, hashbrowns and a scramble w/sautéed onion, bell pepper and cheese. We had honey peppered smoked salmon, which a few of us mixed into our scramble. Mmmmm! Now I don't see this as a bad thing, but I tend to cook just slightly more than needed. Is 18 eggs, 15 biscuits and a pound and a half of bacon really too much for 5 people? 😀 I believe that there should be leftovers for everyone to take home.

IMHO that’s the master plan to sell Venezuelan oil at a much higher price than its value, and making fracking profitable again. The wheel will keep spinning, some countries will face a much tougher time than others. Nothing new under the sun.

The Strait of Hormuz is closed for the foreseeable future and Kuwait, Qatar, Bahrain, Iran, and possibly several others have already had their oil infrastructure hit and set on fire. We just had ~20 million barrels of oil per day get taken off the world market, and if the blockade continues long enough they'll have to start shutting down all the oil fields when storage starts running low. Once the oil fields are shut down they'll take weeks to months to restart production. Oil will not be available at any price. What we have here is what Iain M. Banks refers to as an Outside Context Problem in his Culture series novels.

It's interesting that your 717 seems to have a slow blow fuse, while mine has a fast blow fuse.