timestamp 21:00 that crapacitor is there so it prevents self oscilation you are correct richard but also as a filter depending on the value is the frequency that passes through the highpass filter to filter out the high as it is a subwoofer and only produces the bass
Richard! Oh my. The tolerance band is always supposed to be either closer to the inner edge of the endcap of the resistor, or he thicker band. In this case it's both, but cheap resistors aren't always clear. So this 1K resistor was definitely just sitting upside down compared to the one up top of it. :)
The amplifier circuit shown was dc coupled, which are a bugger to fault find as every component affects the function. I expect that the main reason for the cap in the feed back shown was to block the feedback from affecting the dc biasing conditions. They same way as the emitter bypass cap fitted to increase the gain in a transistor amp.
@@Z-Ack yes but the amplifier is still has DC coupled feedback, meaning that every component except the caps (unless they are leaking) can affect the bias.
checked the place i usually buy from and they had all the log and lin pots bent and straight legs and they want like 1 euro / pcs for log pots and lin pots are 0,88 euro / pcs
I still have the A5K pot. Let's see first if the amp actually produces the correct volume level now. I would much rather replace the pot with a new one.
The values are printed on them with the code. The voltage is sometimes listed as a letter, but sometimes it's not. In that case, it's safe to assume you should either get the high voltage variant or use a reasonable guess of what voltage is present or just check what the circuit is rated for. If it's a 12V circuit, you're unlikely to need a 300V rated capacitor, yeah? Capacitor values for startup delay IC's are often merely just an RC filter, which slowly charges up and provides the timing aspect for startup delay IC's.
Try getting 500k or 1 meg log pots and then to make life more difficult and a spst switch all most imposible to get. allso 4 ring resistors on blue body very hard to read.
Nice to see a class A/B amp. Another great video, Thanks Richard
I'm just glad that I'm not the only person who still struggles reading 5 band of "dark color" on blue resistors after decades of experience.
The electrolytic capacitor in the feedback is high pass filter to roll off the bass eg: 10hz.
Great videos..
Thanks
timestamp 21:00 that crapacitor is there so it prevents self oscilation you are correct richard but also as a filter depending on the value is the frequency that passes through the highpass filter to filter out the high as it is a subwoofer and only produces the bass
As soon as you started to say "This is quite a simple circuit... Shouldn't be too difficult to..."
I yelled out "PART ONE!"
Richard! Oh my. The tolerance band is always supposed to be either closer to the inner edge of the endcap of the resistor, or he thicker band. In this case it's both, but cheap resistors aren't always clear. So this 1K resistor was definitely just sitting upside down compared to the one up top of it. :)
It was. But it made an interesting point in this video I think 🙂
Good stuff
The amplifier circuit shown was dc coupled, which are a bugger to fault find as every component affects the function. I expect that the main reason for the cap in the feed back shown was to block the feedback from affecting the dc biasing conditions. They same way as the emitter bypass cap fitted to increase the gain in a transistor amp.
Rc filter.. basic circuit incorporated with a high pass..
@@Z-Ack yes but the amplifier is still has DC coupled feedback, meaning that every component except the caps (unless they are leaking) can affect the bias.
Heya, yes a second good one would be nice. you could look at discord to see if there is a shematic.
The Devil's own job finding bloody Log Pots (A)
checked the place i usually buy from and they had all the log and lin pots bent and straight legs and they want like 1 euro / pcs for log pots and lin pots are 0,88 euro / pcs
Would a squirt of contact cleaner not liven the pot up? It works on my Guitars
I still have the A5K pot. Let's see first if the amp actually produces the correct volume level now. I would much rather replace the pot with a new one.
28:49 Richard, couldn’t you just work out the value of a fixed resistor to tie accross pins 1 and 2 of your linear pot?
Why is it my all components on my power supply has no Voltages ?
What things that can replace green ceramic capacitor ?
Did it depends on Control IC ?
The values are printed on them with the code. The voltage is sometimes listed as a letter, but sometimes it's not. In that case, it's safe to assume you should either get the high voltage variant or use a reasonable guess of what voltage is present or just check what the circuit is rated for. If it's a 12V circuit, you're unlikely to need a 300V rated capacitor, yeah?
Capacitor values for startup delay IC's are often merely just an RC filter, which slowly charges up and provides the timing aspect for startup delay IC's.
@@AnnaVannieuwenhuyse it has no voltages on my multimeter.
@@petersketch1990 what are you referring to here?
@@AnnaVannieuwenhuyse refer to diode, 200v capacitor and transistor not has voltage on multimeter.
Maybe it has discharge to ground ? I leave it for 2 months actually.
Richard I sent you an email with a link to ebay for the potmeter that is cheaper and with the right kind of legs
Try getting 500k or 1 meg log pots and then to make life more difficult and a spst switch all most imposible to get.
allso 4 ring resistors on blue body very hard to read.
1 minute ago!