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Projects, Designs, and Technical Stuff / Re: Balanced line level input for PCM1804 without negative supply
« Last post by MasterT on Today at 07:05:46 pm » OPA with "zerocross" feature from TI are opa2365, opa2320 and -22 -25.
I don't think opa4376 is a good choise, slew rate is low. ADC is required RC network at the input, to lower current spickes that disstress opa, otherways > 1 GHz GBW 'd be necessary. The problem none of the product capable to satisfy both condition - low THD and extremely high GBW same time.
TLV2365 low cost alternative for OPA series, my recomandation, ( with RC network).
If slightly higher THD is not an isue, than very cheap THS7316, THS7373. Tests show that series have very good drive capability, so RC-kickback 'd accomodate higher C value (0.1uF for audio) and lower R, 10 OHms or so. Of cours THS is better for high freq. application.
I don't think opa4376 is a good choise, slew rate is low. ADC is required RC network at the input, to lower current spickes that disstress opa, otherways > 1 GHz GBW 'd be necessary. The problem none of the product capable to satisfy both condition - low THD and extremely high GBW same time.
TLV2365 low cost alternative for OPA series, my recomandation, ( with RC network).
If slightly higher THD is not an isue, than very cheap THS7316, THS7373. Tests show that series have very good drive capability, so RC-kickback 'd accomodate higher C value (0.1uF for audio) and lower R, 10 OHms or so. Of cours THS is better for high freq. application.
3
Beginners / Re: Direction of Current?
« Last post by thephil on Today at 07:02:45 pm »As others pointed out, current was defined well before we knew about electrons so things seem to be backwards.
But that's OK – electrons are not the only way to carry charge around. they just happen to be the thing that flows through the wires we like to use. Current is just "something carrying charge is moving in some direction." – If something is positively charged things are aligned. If something is negatively charged, like electrons, things seem to be backwards. Just think of technical current as "positive charge moving in that direction" and then, obviously, negative things moving in the opposite direction amount to the same thing.
But that's OK – electrons are not the only way to carry charge around. they just happen to be the thing that flows through the wires we like to use. Current is just "something carrying charge is moving in some direction." – If something is positively charged things are aligned. If something is negatively charged, like electrons, things seem to be backwards. Just think of technical current as "positive charge moving in that direction" and then, obviously, negative things moving in the opposite direction amount to the same thing.
4
Beginners / Re: Direction of Current?
« Last post by PGPG on Today at 06:59:57 pm »Thought experiment: would electronics be any different today, if the direction was correctly in the first place? Would we be using negative voltages for single supply circuits?
But it was.
When I started to learn electronic (when I was 10) the only transistors I could have were germanium pnp. The first transistor radio receiver I was building had + as GND and -9V as single supply. All circuits those time were using negative single supply. First silicon npn I had in my hands was BF520 bought by my friend's mom to darkroom clock I was building for him and couldn't get enough time stability using germanium pnp transistors. This transistor was very expensive. Real value for us was like $100 now. I had to learn reverse electronic when moving from germanium pnp to silicon npn.
5
Test Equipment / Re: Is a $100 Amazon special benchtop VMM sufficient for basic voltage checks?
« Last post by K5_489 on Today at 06:50:43 pm »Sorry, a VMM?
I think you’ve commingled “DMM” (digital multimeter) and “VOM” (volt-ohm meter).
It's more that I was originally thinking "All I REALLY need is a voltmeter...well, maybe a continuity checker too" combined with "these stupid mutlimeters are always in my dang way!" then my brain, in all it's stupid ADHD glory, combined the two to make Voltage Multi Meter. It happens...frequently.
Sometimes I catch it, sometimes i don't. This was a I don't time.... 
6
Test Equipment / Re: New miniature programmable DC power supply - FNIRSI DPS-150
« Last post by 4thDoctorWhoFan on Today at 06:48:00 pm »Does it produce (a lot of) noise/ripple itself or does that just depend on the quality of the input?I have not done any noise/ripple tests yet. I just received it. I have not even tried the barrel jack yet.
Hopefully in a few days I will have time to test for noise/ripple.
7
Projects, Designs, and Technical Stuff / Re: 3-phase diode bridge - 6 separate windings
« Last post by schmitt trigger on Today at 06:46:06 pm »Tim;
now that you describe it, it starts to make sense, let me see if my poor brain has got it right.
Taking as an example windings 114 and 188 are each rectified by its own individual diodes, and the resulting pulsating DC is fed in series to the auxiliary winding 117, which "fills the valley" left over from the rectification of the two other phases.
Brilliant indeed.
now that you describe it, it starts to make sense, let me see if my poor brain has got it right.
Taking as an example windings 114 and 188 are each rectified by its own individual diodes, and the resulting pulsating DC is fed in series to the auxiliary winding 117, which "fills the valley" left over from the rectification of the two other phases.
Brilliant indeed.
8
Test Equipment / Re: New miniature programmable DC power supply - FNIRSI DPS-150
« Last post by 4thDoctorWhoFan on Today at 06:43:01 pm »Obviously...No, not obviously. Perhaps you have no idea what you are talking about. Just saying.
Understand?
Instead of being an arse, how about trying to explain yourself better?
9
General Technical Chat / Re: Reviewing my new 'second' Flip Phone: Jitterbug Flip2
« Last post by BILLPOD on Today at 06:40:41 pm »Good Morning RJSV, Check out 'BLU' brand phones. I picked one up on Amazon for $79,
delivered. https://www.amazon.com/BLU-G0630WW-Unlocked-Android-Smartphone/dp/B0BCH4FL86/ref=sr_1_1_pp_so_CELLULAR_PHONE?dib=eyJ2IjoiMSJ9.meDjKpjU7Bm5b31-Cn8IoQxyyz5ceo7L0aQQptbl97SyWfFD8JQkwUfY4ejYcEUbhMOJ6pLO-MgNkDYdlJA80uH6n7yfBQp6JI7MUWu3h6BQORLr9Qg4VZ-2cZ2SQzqhlU-ejN7tIXLy3lTPNSJ0Ksy62MqwFcCNqsp_UsRPVypR8KH53Aft3LnFQSOEjQ7glJ4Lin-Jwtvmkc12hPnIWg7CizOUdJrR7ddQyJdn2EQ.Ma0oskFCBHWVOYum1RptxhILZ-iwJy4gQWh-mf-UZyA&dib_tag=se&keywords=blu+phones&qid=1726943972&sr=8-1
delivered. https://www.amazon.com/BLU-G0630WW-Unlocked-Android-Smartphone/dp/B0BCH4FL86/ref=sr_1_1_pp_so_CELLULAR_PHONE?dib=eyJ2IjoiMSJ9.meDjKpjU7Bm5b31-Cn8IoQxyyz5ceo7L0aQQptbl97SyWfFD8JQkwUfY4ejYcEUbhMOJ6pLO-MgNkDYdlJA80uH6n7yfBQp6JI7MUWu3h6BQORLr9Qg4VZ-2cZ2SQzqhlU-ejN7tIXLy3lTPNSJ0Ksy62MqwFcCNqsp_UsRPVypR8KH53Aft3LnFQSOEjQ7glJ4Lin-Jwtvmkc12hPnIWg7CizOUdJrR7ddQyJdn2EQ.Ma0oskFCBHWVOYum1RptxhILZ-iwJy4gQWh-mf-UZyA&dib_tag=se&keywords=blu+phones&qid=1726943972&sr=8-1
10
General Technical Chat / Re: Why does the US provide all critical electronic design knowledge to the world?
« Last post by Zoli on Today at 06:40:14 pm »And now he's actively working to get the thread closed; for this kind of behaviour he's sitting on my ignore list.I'm not offended, I'm just dismayed by the appallingly poor SNR. People talking utter bollocks never offends me.
The thing is, you are defining what constitutes "noise" or "bollocks". You don't have the right to impose those on anyone else. If you think there is too much noise or bollocks for your taste, then stay away.
I think there is some useful and interesting stuff coming through. It is the height of selfishness and arrogance to lobby to switch it off just because you are "dismayed".
I'll repeat what I said earlier: if you don't like it, don't click on the bloody thread!! Is that a difficult concept for you?