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@@retireeelectronics2649 was much easy to send me an email saying that they don't have a refund the payment. But if they send me the knobs now I got my money back and free knobs

@@decem_unosquattro9538 always is good to have parts handy when thinkering and trying new projects!

@@SymbolTech21 How right you are ! Yesterday I used two resistors (TH) for a project which was missing components. Imagine if I didn't have a box of different resistors! 😳 In Australia it's actually hard to get components because there are very few shops that stock electronics components now. This is what happens when a country adopts a no heavy industry, no jobs and privatisation policy.

@@decem_unosquattro9538try jaycar mate.

@@decem_unosquattro9538 this happens almost everywhere. No jobs and privatisation

@@SymbolTech21 Exactly its a sinister plot against the working and middle classes. All jobs offshore to China and other Asian countries which exploits them and us.

@@ColinMcCormack thanks he loves the mailbags soon I started opening he was keep coming to check what I have on the mail!

@@gino3286 when upgrading the capacitors on the power supply you can't just put much capacity because more capacity lead to a dead short for a short period of time if is enough if the rectifier diodes are not capable to handle lots of amps to fry them and also to much capacity will stress the transformer so also here u need to take I'm consideration how many VA the transformer is.

@@SymbolTech21 Hi thanks i understand that In fact i would take out also the old diodes Often they are very weak 10A diodes are quite cheap and should fit in fine My rule is 2x 10mF x channel = 40mF total If the space allows of course

@@gino3286 for that capacity I will go with 25A diode

@@SymbolTech21 it seems a lot However even 30A integrated bridge are very cheap The transformer can sustain a short surge I shorted one for half a minute and it is still working Litlle smoke and stop Big caps are very good

@@decem_unosquattro9538 headphones need amplifier

@@decem_unosquattro9538 yes per channel

@@decem_unosquattro9538 need some experience and techniques

@@decem_unosquattro9538 biasing mean that we can adjust with the trimpot the right amount of current on the base of the transistor to open or close the transistor on the right position to don't de neither over drived. The speakers operate on AC current because need to alternate in order to produce the sound. I did the initial test with lower voltage and low current in order to don't burn nothing on the board if by any chance I soldered something wrong. And yes these amplifiers are 120w RMS per channel. If the power transistors are genuine or fake I can't say exactly. Only testing them individually following the datasheet and by applying the max voltage which is rated and drive the max current which is rated. If fails this means is definitely fake

@@SymbolTech21 Thank you for that excellent explanation. I was looking at sine waves and they talk about chopping off the tops of the waves or the bottom of the waves. There are many types of distortion from what I have read. Your explanation explains it much better. So that's what biasing is. Interesting. Which resistor do I need to desolder and I assume I take the 100 ohm out and replace it with a 100ohm trimmer.

@@SymbolTech21 yes it was interesting to reac about AC and how it needs to oscillate as AC does.

@@SymbolTech21 Yes I see you used a 18-0-18 or smaller transformer which I can see is wise considering the damage you might do if you added full power to both channels.

@@SymbolTech21 120W okay that's what they're supposed to be able to handle. I often wonder whether they mean RMS or PMPO. Me being cynical I always think oh maybe that's the peaks not the average RMS rating of those amps.

@@decem_unosquattro9538 is always good to be honest,

@@jclark5956 we try with whatever can be printed

@@retireeelectronics2649 free shipping and at this price is a bargain. I got the jackpot

@@zombieryder I don't tried but will not work. Because 2 reasons. 1 the MOSFET which controls the iron tip will not handle the current and the power supply that is inside the quicko don't supply enough current

@@SymbolTech21 im using modified handle with hakko TX1 150w and TX2 300w cartridges on quicko station to solder thick copper. I dont have t245 currently to test with. Also Im guessing the power rating is about how quickly the tip heats up. Quicko station heats up 300w cartridge just fine though it does takes its time.

@@Mrhifitunes so you need to power the volt amp separately to the tin wires red positive and black negative with 12v then the tin yellow is measuring the voltage and the tick red and black in series with the load to measure the current

@@Mrhifitunes watch this video definitely you get an idea how to connect the volt amp meter th-cam.com/video/YyQQrjfbhkw/w-d-xo.htmlsi=4I6J42jrL1SXCpy1

@@CanaleTH-camGeneralista the T245 soldering handles on the market are ready made for specifics soldering stations. But not for this soldering station controller board. So in case you want to use this controller board the wires arrangement is how I'm showing on the video. I don't know who designed the controller board why they don't kept the orientation pins in order to work with soldering handler right off the shelves

@@SymbolTech21 Thanks for the clarification, I thought the pin orientation on the controller's GX12 connector was already set for the T245 handles, but it's a bit annoying to remove the handles to change the cable layout. Thanks for your help and for sharing your project. Regards.

@@CanaleTH-camGeneralista hope you found this video informative!

@@SymbolTech21 Yes that was very helpful, thanks again.

@@takiecary I will probably try to get some genuine opamps and give a try, but also the tpa3255 probably is not a genuine so I don't think will change in power just changing the opamps.

@@takiecary I received some amplifiers with the same chip tpa3255 so I will have soon video reviewing that amplifier and I will do a comparison with this board from AliExpress and get a conclusion. Stay tuned for that video

​@@SymbolTech21 Great! Im about to buy some tpa3255 board but i don't know which one is good so i will be waiting for your comparison. I hope you will also tell something about sound quality of the different boards.

@@takiecary the amplifier I received is not just a board. It's a complete monoblock amplifier but is based on the same chip tpa3255 and will be definitely the way to understand if the board from AliExpress have a fake chip on

@@Audiopulse9 is my own design

@@Audiopulse9 is my own design

@@jamesw5584 yes definitely is a better amplifier kit this

@@jamesw5584 yes I agree with you this is not a good amp at all and if you watch the entire series you will find trying other amplifiers kits and I choose a good one to make the final amplifier

@@CarlosSeta-v5p let me check if I can find the code because was an old project and I have a new PC now

you will find the code on the second link

@@SymbolTech21 Thanks so much for reply, but the second link has the Arduino Schematic, sorry but i'm terrible with IT thinks

@@CarlosSeta-v5p the second link that says the code so will be the third link on the row

@@SymbolTech21 , thanks so much for take the time to replayme. But in this link there is only one file (for stm32 for the name of the file y the used libraries) can I use the same file for arduino? Bests.

@@fredcailloux2526 l12 is really good amp with the dual 28v transformer I doubt that you will get the 100w power from the l12. Yes I'm planning to try the c3850. Thanks for your comment

@@care2726 I didn't test it I will see how will work when I will test it.

I will do also that one in one day. Thanks

@@DjRedSnowCh will shows you on the display the steps. First you need to short all 3 probe pins and press the button for testing will go in calibration mode

@@SymbolTech21after i calibration Done. i open probe and test press button display is show value caps 😞 it don't show no part or part damage. I check the connect circuit is true

@@DjRedSnowCh you need to have also a 100 nf capacitor to insert for testing during calibration

@@SymbolTech21 yes i insert 100nf. and last step i insert 30nf. Display is show END TESTING. I want contact or email I want to show the picture for you

@@DjRedSnowCh if shows end testing the calibration is finished

@@bertilstroberg5382 thanks for your suggestion, I will give it a try also with the pots on the middle position. Let's see if can be flat on frequency response

@@roberttriner6242 thanks for suggesting, usually I do also square wave but definitely I forgot to do in this video I still have the boards so I will see soon as possible to do a video on it injecting also square wave

@@martinsmith8946 thanks I really appreciate it

@@mtrltoolman the circuit protection sensitivity can be adjusted with a trim pot the power supply that works the circuit is 12v

Ok The wiring not clear to me, but I think it is like this : Power Supply > protections > buck converters. is it correct? ​@SymbolTech21

@@mtrltoolman the main regulated power supply is controlled by the protection circuit and there is an other switching mode power supply 12v which power the circuit protection board

@SymbolTech21 is there any way to connect the trim pot of the current protection with the variable resistor of the current control? If this modification can happen it will be better for any load . You can make your youtube channel more popular with making circuit diagrams and wiring diagram of your works , maybe a blogger site or Facebook page with the channel. Good luck 👍

@@mtrltoolman yes the trim pot can be swapped for a potentiometer and mounted on the front panel like that you can regulate the trigger point on the current desired

@@MrAlb3rtazzo looks like this model don't like low impedance

@@danishdart in sound I find it more crispy the treble and a wider sound stage and I noticed as well that there is a bit of noise when I'm not playing the sound but this matter I need to check with a better power supply that have more smoothing capacitors. The bench power supply have only 3300uf so for a better smoothing I believe at list 10000uf will be better

@@SymbolTech21 The 'crispy' sound, sounds more like higher frequency distortion. If your power supply is switchmode it could definitely be adding distortion.. For which you'll need better smoothing capacitors.. Or perhaps a linear power supply. Good luck.

You can do a full recap on the technics amplifier and bring it back to life on all his glory

@@2000nurek thanks for your comment. This was not mine amp. Was a friend and I did this upgrade long ago and what I remember my friend he bought all the parts so I'm not the one who chose the parts

@@mayoortechinnovations should show on the display all the instructions.

@@SymbolTech21 please is it normal to get random values if I didn't calibrate the device, or there is something wrong with my setup?

@@mayoortechinnovations you must check the resistors to be connected correctly and all of them to be almost the same value because if is tolerance between them will not measure correctly

Thank you very much for your guidance and replys, it's finally working now, the only thing I noticed is that the it keeps requesting for calibration any time I power on, even after a calibration before switching off.. is this normal?

@@mayoortechinnovations is doing the same also for me but I ignore that and measures fine. Definitely need to work on the code to put a functions once is calibrated to don't ask all the time for calibration

@@bohdan2752 I never had this experience with wima. Hope the wima you may used they were not genuine. Definitely there is much better caps out there but the price of one cap is the cost of 50 wimas. Need also to stay in a budget as well

@@SymbolTech21 i use Digikey or Mouser only.

@@bohdan2752 so definitely should be genuine parts. I personally didn't notice any harsh on sound using these caps

Thanks I really appreciate it. Yes soon I will test the tpa3255 and I will have a video on it

@@antoniorodolpho6835 just send me an email

yes you are totally right. soon as I get a paper and a pen my little boy took them from me and with the connectors yes is a good idea as well. I have few more preamplifiers kits to build and test and I will chose the best one for a final project! Thanks for your comment!

@@memyshelfandeye318 it's just a pre-amp and is class A so one transistor drive all full sine wave so no need thermally coupled. When 2 transistors drive the full sine wave yes you will need it but not on a preamplifier.

If you click on the listing link of this kit you will find the schematic on description and then you will definitely understand that is one transistor which drive the signal. about the capacitors if will perform well when I will run some tests easy I can get some high quality capacitors and change them. regarding the power supply how you can see also on the video I didn't populate it because I know is always better the power supply to be separate from the preamplifier board.

@@iceberg789 I tested and already filmed, soon I will have the video on TH-cam. Just a little editing put together the clips

@@plexon2006 www.ebay.co.uk/itm/322821956499?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=biMeahOQQKW&sssrc=4429486&ssuid=e2bvqqopq7c&var=&widget_ver=artemis&media=COPY should be this link

I see, from Ebay. Do you have a lik, if possible? Thx

@@petercornell2002 yes from eBay

@@petercornell2002 www.ebay.co.uk/itm/322821956499?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=biMeahOQQKW&sssrc=4429486&ssuid=e2bvqqopq7c&var=&widget_ver=artemis&media=COPY a link for this

They are all within 1%

⁠@@petercornell2002but the measurements aren’t consistent, at a one moment a resistor measures 100.4 ohm and the same resistor measures 100.1 the next measurement. And I believe I have seen there was a resistor that was below 99 ohm. But I’m pretty sure that when you warm up these resistors between your fingers the difference wil be even bigger. I do however think that this kind of component matching doesn’t make much of a difference. For example calculate with an output difference of 1% in a power amplifier. 10 volts into 8 ohms gives you 12.5 watts, 10.1 volts into 8 ohms gives you a difference of 0.75 watts and that is 0.25dB. That isn’t noticeable for most (any?) humans. I would worry more about the difference in potentiometers. I have seen original ALPS RK series pots with tolerances between both sides more than 5%. The Chinese ALPS pots found on eBay / Ali Exp have way higher differences.

@@RTBNL these differences may be from the multimeter that was on auto mode on next video when I will use it I will switch on manual mode and we can definitely understand what is. The resistors or the multimeter on auto mode

@@RTBNL I believe is the multimeter on auto mode

@@SymbolTech21 the automatic range switching should not be of any influence for the results as long as it ends in the same range. If you have some resistors left you can try heating them up a little. Many of these metal film resistor might originate from china and they are prone to be very sensitive to temperature changes. Don’t torch them but just hold a hot solder tip a few millimeters beside them. You might be amazed how much drift there is.

@@Royal_job_Info should be a link on description

@@SymbolTech21 bro insted of using SCL and SDA in OLED display which pins are used in LCD DISPLAY please 🥺🥺

@@Royal_job_Info but I didn't used an oled display. Is an LCD 16x2 display and is connected to Arduino normally how is connected in LCD display library sketch samples

​@@SymbolTech21 You used UNO in schematic diagram Bro but I'm used Nano in practical please tell 😢😢

@@Royal_job_Info the pins are the same to Arduino nano or Uno both are using the same microcontroller chip

@@ericblenner-hassett3945 I noticed that the longer nozzle can be removed and will have a shorter one.

@@AnotherMaker yes that nozzle for heat shrink are really useful to.

@@jw200 happens to me as well some time to buy so much stuff

@@brankozivkovic6555 sound really good.

@@CraftyZA this is more better because have over current protection and voltage protection and also do constant voltage and constant current

@@SymbolTech21 I've added it to my cart. The link you initially shared on the bag video no longer works, but a few stores still stock it. One just needs to do a search.

@@CraftyZA when I put out the video and the link was still available

@@CraftyZA I upgraded to this th-cam.com/video/yaxJYI5ejf0/w-d-xo.htmlsi=POR8U-BxrRNNfWsX