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February 23, 2024, 08:09:34 AM

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saturated's all encompassing inclusive and exclusive bin thread

Started by saturated, September 10, 2023, 03:09:27 PM

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saturated

figured i was starting too many threads and it would be better to keep it all in one place

gonna be posting some stuff that is painfully obvious to the more skilled members here yet is an epiphany for me  ::)

btw everybody here has been super cool and helpful

so here we go

 :)
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

saturated

i did a breadboard experiment where i measured voltages and calculated voltage drops

also they wanted me to take measurements at certain points rather than across each component

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and im amazed at how close they came out...although i messed up on point D gonna have to redo the experiment

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even though i had the ac? portion of the circuit on the left it was a non factor as I couldnt really get anything out of it.
maybe that was the point

still im missing that 1v pp

gonna have to do some more calculation


I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

g1

What is the symbol in the circle on the far left side?
Can you post the circuit from the textbook?

It looks to me like there is an AC source on the left side (circle with symbol), and a DC source on the right side.  That should not be done.  You can not get a p-p voltage from a DC supplied passive circuit like that.

saturated

thank you sir

here is the reference

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i thought it would be the 1 v riding on the dc like a 25v tall wave

at the end of the day all i did was make a dc circuit

 ::)

ok after further review....looks like i need to work parts 5 and 6

doh
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

saturated

ok i repeated the experiment...and did the measurements for 5 b

still need to do the calculations 5 a

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also my scope and probe needs to be calibrated...

 :P

also that dc measurement at point d looks better this time

got tons of pics but figured i would chill out and stop posting millions of pics
if you need to look at something let me know

the capacitor i used is electrolytic was in a pickle about the orientation....
 :o but its still alive

I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

Tassieviking

What sort of breadboard are you using ?
If you haven't got a solder-less plug in breadboard I would highly recommend you get one.
https://www.taydaelectronics.com/hardware/breadboards/830-point-solder-less-plug-in-breadboard.html

As you get further along you are going to get more and more components and gear, I would recommend you find a good value place to buy your components in bulk.
I use Tayda to get most of my supplies as they are cheap and I only build stuff for home use, if I was going to sell my gear I might buy more expensive components but I find Tayda is more then good enough for me.

I buy resistors in lots of 50, capacitors in lots of 10 or more, diodes usually 50.
I build stomp boxes and amps for family mostly so I find that amount will keep me going for a while, if I bought the components locally I would pay more for a bag of 5 resistors then lots of 50 from Tayda.

There are bound to be more good value shops around but I will stick with Tayda myself as they send the components in nice little zip-lock bags.

I usually buy a fair amount at a go because of shipping costs to make it cost effective.

Cheers
Mick
 
There are no stupid questions.
There are only stupid mistakes.

saturated

thank you sir i am using a jameco board

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pretty funny last night at work i was calculating voltage drop for the ac circuit and trying to figure out which side was +

so i was like oh yeah look at the terminals of the bnc cord from the SG

then later i was

....oh ok........ ::)  :)



I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

saturated

thats cool that you like pedals

maybe somebody would like to see my old pedals

here is one i bought almost 40 yrs ago

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i actually never cared for it much made it sound like a chainsaw



I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

Tassieviking

There are no stupid questions.
There are only stupid mistakes.

saturated

  I looked at that tayda website they seem like some good people i will have to try them out next time. 

I unearthed this yesterday wondering if i could use it

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despite being out in the weather they actually still spin

says powerstat 20

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probably too far gone to be useful
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

Tassieviking

I would say they are too far gone, but when I zoomed right into the copper windings it looks like the varnish is still good.
They look like nice rheostats that might be ok after a full restoration, but it depends on the metal having survived in the core.

If they clean up ok they could be re-dipped in varnished then tested too se if they are ok.

Rheostats are very useful for bringing up the mains voltage nice and slow when testing electronic gear.
I have a small one and a large one myself.

What are the ratings on them ?
There are no stupid questions.
There are only stupid mistakes.

saturated

hello sir here is another pic

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and of the complete device which purpose is unknown

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brief google of "F. F. Hutton" shows they were active 1950s era and known for pneumatic devices.....

probably not much help but here is rear

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I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

Tassieviking

It looks ok, they need a big overhaul before you would know if they could be saved.
So it's 120V AC in and you can get 0-140V AC out at 3 amps, say 400 watts.
They would be very nice on a workbench, but they would have to be enclosed with a lead for input and a power outlet for outlet voltage if you are not a qualified technician just for safety.

Me, I would salvage them and use them, but I know whats involved having been a licensed electrician since 1980.

The main worry I can see is rust in any steel parts as that might have caused an internal short in the windings, all the rest can be cleaned and inspected very gently.

It might be cheaper to buy  a new unit with the time and effort (and money) it will take to restore them, but I still would.

Mild soap and a toothbrush would be my starting point, some WD40 to loosen up any seized nuts and bolts and slowly pull them apart.
Some electrical cleaner on the electric parts, rub the windings that have been bared for the carbon brush to run on with something slightly abrasive, you can get stones made for polishing up commutators in motors that are perfect for that.
(I often clean contacts with an eraser made for ink, especially old PCB's before soldering)

Reassemble and bake in an oven to remove moisture and test the insulation with a HV megger, all done.
There are no stupid questions.
There are only stupid mistakes.

saturated

thank you sir i will ask him if he wants to part with them

I did some more breadboard tonight same experiment but with a 100 uf cap across a resistor

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im confused by that 0.4v but i think my ground adj is off or something having to do with where my scope probes are...idk

its probably supposed to be 0.0v

but the scope def shows what happens

and the multimeter showed the dc circuit voltage readings were unchanged by the capacitor

 :P
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome

saturated

btw sir I had no idea what an HV Megger was..so I enjoyed reading about it.

nothing to do with it but reminded me of when i was trying to fix our dishwasher.
I removed the circulation pump and tested resistance..it was some crazy number like in the mega ohm range.
I was like "yep thats no good!" and ordered a replacement.
when the replacement arrived I checked resistance on it...and it was the same.

however the replacement pump fixed the dishwasher.

later i was reading that those pumps(motors) are something called ? continuous phase synchronous ? motors

:P

EDIT  supposed to be SINGLE PHASE
I ask stupid questions
and make stupid mistakes

criticism, critique, derision, flaming, verbal abuse welcome