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Everything else equal, a lower burden voltage is better. But also, if everything else is equal, the lower the burden voltage, the higher the noise. And the lower the burden voltage, the lower the accuracy. So pick your poison.
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Beginners / Re: Lab PSU for learners
« Last post by AcdNrg on Today at 11:18:49 am »
I thought about DIY the PSU as well, but prefer something that "just works" for now.  No doubt the next Eurorack case will get a DIY PSU, but for reference, easy of access etc I go with something commercial first step.
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The problem is that we cannot prove the efficacy of any "immunization" program for COVID at this time.   

Someone could just as honestly say that they have had no shots and have taken no or minimal precautions and have not became ill at all.  There are lots of people who could say that.   

To evaluate the efficacy we need proper studies, not just personal observations of ONE subject.  At this point, it will be very difficult or impossible to get anything close to randomized studies.   
How do we know it reduced symptoms in "vaccinated" people? I have seen no believable proof of this. Maybe someone could post some studied proving this.
Zero has a point, People who have had the shots were deemed to be infected by the testing done (for what that is worth) and told to isolate.  Authorities thought that these people were prone to communicate the virus in spite of their "immunization" status.  And, Yes, we were told that getting the shots would protect others.   Which one is it?
This sort of "logic" is why many people have no confidence in the authorities as far as their handling of the COVID pandemic.   


Quote>Quote from: Halcyon on Today at 02:45:05 am>Quote from: Zero999 on April 29, 2024, 08:51:34 pm
We were told to get vaccinated to protect others which was a lie. Our government even mandated it for care home workers and they were going to also mandate it for all frontline NHS staff. Fortunately they realised it didn't prevent transmission and cancelled mandates. The authorities have pushed far more misinformation, than crackpots on the internet.

I prefer to stick to the hard evidence. I'll believe it when I see proper, randomised data to show it works.

What a load of crap. Whilst the vaccines might not have prevented all transmission, it certainly had a significant impact on transmission rates and for those that still ended up catching COVID, it significantly reduced the symptoms in most vaccinated people. There's plenty of evidence that supports this. The fact is, the vaccination programs saved a lot of lives and made the lives of millions of others far less miserable.

I continue to get vaccinated against COVID every 6-12 months based on Australian government and doctors advice, and I'm yet to catch it. I spend quite a lot time on public transport and around people as well.

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Beginners / Re: Lab PSU for learners
« Last post by AcdNrg on Today at 11:15:35 am »
Another approach could be "go as you grow"

Makes sense, although getting +-12V and +5 in a single box automatically led me to the Rigol. Thanks for posting the other option, I will look into that.
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A follow up on this. I finally managed to redesign and test the circuit. I decided to temporarily remove the 555 time-out alarm as the trigger needs to be toggled to start counting, not just stay low. And it's not a critical feature now. I could have removed the 7402 inverter and pulled the optocoupler (PUMP_ENGAGE) and relay signal (!AUTO_FILL_ON) directly after R9, but I left the inverter in place, as I hope to get the timer working later.
However, I see 426mV on the optocoupler when it should be 0V. On high, I see 1.15V which is the forward voltage of the LED, so all good. I'm not sure if this will cause any issues with the optocoupler.
I removed R19, and the optocoupler input is 0mV. What's the trick here? If there is a simple mod for the existing PCB it would be good.
And a more fundamental redesign for my next revision?
Also does the relay transistor need a pull-down?
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I have a problem with the DG812:
When i set up a low limit of 0V and a high limit of 3V, then still after choosing harmonics waveform, the limits are exceeded by far.
Is there something i can do here? I tried many values. But when setting up a square, and choosing harmonics (which will happen by accident sooner or later) again, the level is again exceeding the limits.
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Beginners / Re: Electronics primers, course material and books
« Last post by armandine2 on Today at 11:03:08 am »
If you want to, Make PCB like a Pro - should be available on kindle shortly

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Repair / Re: Amprobe HD160C DMM--- Looking for the service manual.
« Last post by Paceguy on Today at 10:57:05 am »
Thank You Kosmic, I will go thru the entire cal proceedure, it could be out of cal according to the final note,  since it's 1Err that I'm getting on the AC setting and 3Err was first showing on the current ranges. Thanks again!
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Understood   ^-^
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Thanks, the El Cap that we need ESL and ESR for, at 450khz, is...

EDH477M050S9SAA
https://www.mouser.co.uk/datasheet/2/447/KEM_A4049_EDH-3316662.pdf

Also, need ESL and ESR  for a 10uF, 50V, 1210, X7R   MLCC
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