So 1/2W or 1W resistors?
36V-63V caps, of the sort you wrote?
Different standard FET, J-FET, MOSFET, BJT's and some switches, IC's of the 7400 series, some 555 and?
36V-63V caps, of the sort you wrote?
Different standard FET, J-FET, MOSFET, BJT's and some switches, IC's of the 7400 series, some 555 and?
0.5 or even 0.25 watt. Remember that anything over around 3.9k can not dissipate more than a quarter watt on anything up to 30 volts and that should cover you for most experiments.
I played a lot with 7400 IC's and as long as you accept their limitations (5v supply) they are great to experiment with and pretty tough.
555 timers (the old original type, not CMOS) are another great learning device.
An NPN and PNP complementary pair of power transistors like the TIP3055 and TIP2955 bolted to a heatsink are also extremely useful.
Caps can be either 63v or a mixture of 16 and 63. All depends what sort of things you want to do.
A plug in breadboard and good adjustable power supply are two of the most useful items. The power supply should cover 0 to 30 volts and have a good adjustable current limiter that operates down to milliamp levels.
I have two similar to these. WOW, can't believe the price... I paid about £20 for the pair at an amateur radio rally.
FARNELL L30-2 L302 STABILISED POWER SUPPLY | eBay
There are lots of these kind of things available new these days at really good prices.
I played a lot with 7400 IC's and as long as you accept their limitations (5v supply) they are great to experiment with and pretty tough.
555 timers (the old original type, not CMOS) are another great learning device.
An NPN and PNP complementary pair of power transistors like the TIP3055 and TIP2955 bolted to a heatsink are also extremely useful.
Caps can be either 63v or a mixture of 16 and 63. All depends what sort of things you want to do.
A plug in breadboard and good adjustable power supply are two of the most useful items. The power supply should cover 0 to 30 volts and have a good adjustable current limiter that operates down to milliamp levels.
I have two similar to these. WOW, can't believe the price... I paid about £20 for the pair at an amateur radio rally.
FARNELL L30-2 L302 STABILISED POWER SUPPLY | eBay
There are lots of these kind of things available new these days at really good prices.
Sorry but it does not that way.
To begin with , LEDs are *current* controlled, while pots, if fed DC, will supply varying *voltage* at the wiper terminal.
To boot, LEDs are HIGHLY non linear if voltage controlled and they have a definite threshold below which they practicall pass no current and definitely produce no visible light, so even if you had your Log/Antilog pot it will NOT work the way you expect, by any means.
What he needs to do is take the wiper of the pot to an emitter follower that then powers the LED via a fixed limiter resistor.
You can then work on that set up and add a preset amount of fixed bias to just ensure the LED is coming into conduction.
Remember he wants to experiment 🙂 and that is the best way to learn.
Yes sounds logical and should cover most.
Now you say a power supply, I think I want to buy a good one, not a fantastic one but still better then the worst from trash and scam corp. 🙂
I think of a model with keypad, possibility for +/- V and maybe 5A, what do you say?
Now you say a power supply, I think I want to buy a good one, not a fantastic one but still better then the worst from trash and scam corp. 🙂
I think of a model with keypad, possibility for +/- V and maybe 5A, what do you say?
It all depends how much you want to spend but I would say that a good power supply is up there with an oscilloscope for usefulness, even more so when you are just beginning.
Some have dual (split supplies) which are useful. I have to connect both my supplies in series to do this. 5 amp is a lot... I can cover 99% of stuff with 1 amp for initial prototyping.
https://cpc.farnell.com/tenma/72-13...j-fixed/dp/IN07981?st=adjustable power supply
I personally would avoid ones with complex keypad entry. You just want a knob you can turn to set the voltage and current. In the same way I'd take a simple microwave oven with rotary controls any day over a more complex one.
That's it for now 😉 time to play out and cut the grass.
Some have dual (split supplies) which are useful. I have to connect both my supplies in series to do this. 5 amp is a lot... I can cover 99% of stuff with 1 amp for initial prototyping.
https://cpc.farnell.com/tenma/72-13...j-fixed/dp/IN07981?st=adjustable power supply
I personally would avoid ones with complex keypad entry. You just want a knob you can turn to set the voltage and current. In the same way I'd take a simple microwave oven with rotary controls any day over a more complex one.
That's it for now 😉 time to play out and cut the grass.
Yes okay hmm, but to bring it further down at my level🙂
Lets say I have two LED's and I want to be able to dim them both individually. I could of cause build two current sources with a pot to dimm the light.
And I could do the same if I would adjust 50 LED's but isn't there a way to use a single current source and then add a dimm-pot for each LED?
Yes I do understand the part about using a turn button, but for different reasons, do I feel it easier and more precise to press some numbers.
If I combine two PSU's with keypads, do I properly get what I need and maybe cheaper.
I do not know what I want to spend, but I see no need for buying the top brands, like keysight for $2000.
I am willing to save money up to get the right solution.
If I combine two PSU's with keypads, do I properly get what I need and maybe cheaper.
I do not know what I want to spend, but I see no need for buying the top brands, like keysight for $2000.
I am willing to save money up to get the right solution.
Most 'log' pots are not log response at all anyway. Using linear taper to emulate logarithmic gives much more repeatable results and accurate channel matching, which is normally more important - unless you need a calibrated scale. Log pots are cheaper as you only need a single gang, which is why they are made.