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Solid State Amplifiers => The Newcomer's Forum => Topic started by: saturated on December 17, 2024, 04:20:47 PM

Title: Newbz and DC power supplies
Post by: saturated on December 17, 2024, 04:20:47 PM
If you listen to fools...
The newbz rules.... xP

Anyhow...been looking at power supplies

I'm trying to decipher terminals that show up in the pictures 🖼� of many of them

I have attempted to identify and lable appropriately....

What the heck is S- and S+ ?

IMG_20241217_150812351 (1).jpg

Thank you in advance  :tu:

Also I'm seeing older power supplies that are called switch mode I'm kinda familiar with those rectangular plastic ones that look like what hooks to laptops and stuff but I guess early older switch mode externally kinda looked like linear power supplies I see some called Op-Amp power supplies.

Also I see some schematics for a (7815 and 7915 ?) power supply looks like I could assemble if you like that. 

 :loco



Title: Re: Newbz and DC power supplies
Post by: J M Fahey on December 18, 2024, 08:22:11 AM
Most probably.

Set meter to 200V scale (just in case), Black probe to COM, measure all others with red probe, you will get positive and negative values, attach little stickers to identify them.
Title: Re: Newbz and DC power supplies
Post by: g1 on December 18, 2024, 02:03:37 PM
Quote from: saturated on December 17, 2024, 04:20:47 PMI'm trying to decipher terminals that show up in the pictures 🖼� of many of them

I have attempted to identify and lable appropriately....

What the heck is S- and S+ ?
I can't guarantee that this is correct, but seems to make 'sense'.  :)

https://forum.allaboutcircuits.com/threads/open-chassis-power-supply-connections-s-and-s.69047/
Title: Re: Newbz and DC power supplies
Post by: saturated on December 18, 2024, 04:19:07 PM
Well the senseis have spoken.  :trouble

Thanks guys instead of buying more stuff  I'm gonna get some 7815 and 7915 and give it a go.

As usual I need to think of some stuff handy to have to add to the order to help with shipping  xP

I would like to submit a hijacked schematic unscrupulously stolen from teh web  :loco
for your perusal
15V-Dual-power-supply-circuit-7815-7915.png

If you like it I will use it.

Thanks


Title: Re: Newbz and DC power supplies
Post by: phatt on December 18, 2024, 08:08:54 PM
Yes that will work.
Just note that C5 & C6 should be no more than about 10uF as the regulators have already done the hard lifting.
I can't recall but big caps there can cause issues.

Not critical but the diodes only need to be 1N4004, 1N4007's are rated at 1,000volts. while 1N4004 is 400Volt, plenty of head room and slightly less voltage drop.

I personally like to put the Fuse First but up to you.
Phil.
Title: Re: Newbz and DC power supplies
Post by: saturated on December 18, 2024, 08:41:12 PM
Yes sir thanks

nice to hear from you

Happy Holidays sir  :tu:
Title: Re: Newbz and DC power supplies
Post by: joecool85 on December 19, 2024, 11:18:18 AM
Quote from: phatt on December 18, 2024, 08:08:54 PMI personally like to put the Fuse First but up to you.
Phil.

100%  Always put the fuse as the first thing inline with the power input.  That way if there is an issue with the switch, or anything after the switch, the fuse will take the heat.
Title: Re: Newbz and DC power supplies
Post by: phatt on December 29, 2024, 07:16:06 AM
Quote from: joecool85 on December 19, 2024, 11:18:18 AM
Quote from: phatt on December 18, 2024, 08:08:54 PMI personally like to put the Fuse First but up to you.
Phil.

100%  Always put the fuse as the first thing inline with the power input.  That way if there is an issue with the switch, or anything after the switch, the fuse will take the heat.
You got it, also I'd add that keep Main wires Separate from Secondary wires for extra safety. I've seen a lot of Big name brands tie Primary & Secondary in a bundle and it's not allowed in Military and Medical electronic Equipment for the obvious reason that if there is a Catastrophic failure it could connect mains to YOU which obviously would not go down well in a hospital. :trouble   
Title: Re: Newbz and DC power supplies
Post by: joecool85 on December 29, 2024, 10:59:37 AM
Quote from: phatt on December 29, 2024, 07:16:06 AMYou got it, also I'd add that keep Main wires Separate from Secondary wires for extra safety. I've seen a lot of Big name brands tie Primary & Secondary in a bundle and it's not allowed in Military and Medical electronic Equipment for the obvious reason that if there is a Catastrophic failure it could connect mains to YOU which obviously would not go down well in a hospital. :trouble   

100% agree.  I forgot to mention in this thread, but I bring it up all the time - make sure to NOT put any mains lines on a PCB shared with anything else!  I can't stand it when I see electronics like this.  It's just asking for an issue.