#124

And a bit about handling a LED

[@TheRadioShop]

I like the green LED much better than all red ones. Yes it was a simple fix but you shown how to go back to basic electronics. Something we seem to forget at times. Great video Peter and thanks for sharing. 73 Buddy

[@TRXLab]

Thank you Buddy, yes I put a bit basic electronics into it sometimes it is helpful for starters..Hope you are already feeling better my friend..73

[@toddanonymous5295]

Hi Peter, I bet Gustav Kirchhoff would have liked your video and so do I. Amazing all the great science and engineering that came from Germany. Thanks for all your interesting and informative videos. Yours are some of the best.

[@TRXLab]

LOL yeah Kirchhoff would be happy. Thanks for watching Cheers

[@fredskalski3601]

Thanks Peter for the very informative video. I always learn a lot on them. I would also prefer the green LED over the red. One thing though, I would have read the voltage across the 330 ohm resistor and then use that with the formula to calculate the current thru the circuit. Thanks again and keep the videos coming!!! 73, Ski

[@TRXLab]

Thanks for your contribution 73

[@arthus1971]

Very good, I wondering is you can explaine more about calibration of 3005D and when is necessary. Greetings from Santiago de Chile

[@OrbiterElectronics]

I like doing this sort of thing too Peter.. I really helps in identifying what's going on. When everything is red it all blends together so important things can be easily overlooked. Nice job my friend. Regards John

[@TRXLab]

Thank you John, yes that is exactly the point it can be easily overlooked...Regards Peter

[@BryanByTheSea]

For a second I thought you were discharged from the hospital with a wristband, then realized it was a ESD wrist strap

[@TRXLab]

Oh my gosh happy that is only the ESD wristband LOL....Thanks for watching

[@danielroibert5631]

Hello, very beautiful video. Did You noticed that blowholes are blocked when your apower supply is stuck between two other devices. He cannot have of airflow and thus no cooling there. The alim is probably going to warm and burning if you fire 5A out for a long time.

[@TRXLab]

Thanks for warning and rising the hand, Daniel! 73

[@karlfell3768]

I did exactly the same thing with mine apart from adding a green led to the CV indicator as well. I also added a quieter fan and a thermal switch so the fan was only active at over around 40 degrees. Nice video Peter. Karl

[@TRXLab]

Hi Karl, I have heard about the fan problem but mine seems to be a newer revision the fan ist just fine.. Thanks for watching 73

[@PapasDino]

Nice for beginners to see that making small mods to their equipment can be relatively easy to do thus making them more useful to you specifically. The green LED appears to be slightly less bright than the red ones but that may be a artifact of your camera. If it is dimmer I think you could adjust the current limiting resistor within reason to brighten it up a bit. Sometimes LEDs are just too bright! I have one piece of gear that had a constant green LED engaged. I tried the resistor adjustment trick but couldn't bring the brightness down sufficiently; I ended up putting a piece of masking tape on the inside of the case over the panel hole it shone thru and that did the job...sometimes the simple fix is right in front of your eyes! Thanks Peter! 73 - Dino KL0S

[@TRXLab]

Yes a bit basic electronics for beginners, Dino. The green LED was a lower mcd type and you are right it appears to be less bright. Need to order higher mcd LED's anyway. Thanks for watching. 73

[@joepereira3421]

Enjoyed watching Peter thanks for your efforts

[@TRXLab]

Thank you Joe! 73

[@Elektronik-1]

Gelernt hab ich zwar nichts, unterhaltsam wars aber trotzdem. Was für ne Kamera benutzt du eigentlich? Mir fällt immer wieder auf, daß die den Focus bei nah/fern Wechseln sehr gut hinbekommt.. Meine hat da immer mal wieder Probleme.

[@TRXLab]

Das hätte mich jetzt auch gewundert wenn Du hier hättest was lernen können bei Deinen tollen Videos die Du online hast. Trotzdem schön das es dir gefallen hat...Meine Kamera ist eine sehr günstige Sony HDR-CX240E mit Zeiss Optik. Danke fürs vorbeischauen.

[@g1fsh]

nice little video Peter. informative as always. very well explained

[@TRXLab]

Thank you Gary. 73

[@Hugatry]

Simple, but great modification. I might do the same to my KA3005 and maybe change the constant current (C.C) to something else as well. It's annoying when I don't notice that the current limit has been reached and circuit starts misbehaving.

[@TRXLab]

Glad that you like it. Thanks for feed-back Chees

[@edmunddrozek4728]

I fully agree this LED location should have been designed by Korad with a green, not a red color! Nice to see such product usability improvement posts! General comments: In this demo of the (discrete) LED change, it looks like the red LED was a 5mm and replacement a 3mm diameter, thus the slight reduction in light coverage. Best light coverage in this case (i.e., viewability through the panel) could be accomplished using a flat top (aka cylindrical) body LED. Looking at other reader's inputs it seems that some of the newer power supply board builds are now using SMD (surface mount device) LEDs, which require a bit more skill to replace. For best visibility of so-called "green" LEDs, I recommend using LEDs with a wavelength of 525nm, not the more common 565 nm (which are closer to yellow when you compare the two lighted side by side). For others contemplating creating status lights for a project, or just for more information on the preferred colors for status indicators in general, I suggest a review of ANSI/VITA 40 (2003).

[@TRXLab]

Thanks for contribution and thanks for watching Cheers

[@judges69]

They are nice power supplies, great idea. looks good

[@TRXLab]

That is really a nice power supply. Thanks for watching 73

[@k1mgy]

Also, have you seen Dave Jones EEVBLOG review of this PSU and the issues he discovered? Beware of overshoot on turn on under some circumstances. Hopefully yours is a later model and is clear of the issues!

[@TRXLab]

Yeah but as far as I know he had a transformer which was not build for the main power in Australian.. It seems to be a newer revision too.

[@k1mgy]

Excellent. You might just make certain that in all conditions the voltage delivered at the PSU terminals will not overshoot when the output is enabled. In one of Dave's tests, this happened consistently. Although a +13.8V radio won't break until around 16.5 volts, other circuits under test could be destroyed should such a fault be present.

[@TRXLab]

you are right I will double check it! Thanks for info

[@larryk4mu240]

Hi Peter, I like the green much better also. Thanks for video. Nice PS also. 73

[@TRXLab]

Thanks for watching Larry 73

[@k1mgy]

Any thoughts on the purpose of that aluminum partition plate that hovers above the power transformer in your Korad PSU?

[@TRXLab]

Hi Mark, I think it is a kind of shielding but would need to do some tests to be sure...

[@SammysHP]

A bit late but it guides the air from the fan to the transformer.

[@bcrawfrd]

Is it possible that the LED is red as a warning to you that you’re outputs are now live.. Maybe an amber light might be a better choice than red.

[@TRXLab]

Well Bill you can hold it how you like. I decided to implement the colour I'm used to over the years...

[@priestblood]

hi great videos,can I ask how did you connect lcd tv to oscilloscope as I would like to put a old 3 inch scope on a 17 inch lcd tv I have can you help please

[@TKomoski]

Wayne I would use a video camera just in front of the screen and display it on a larger monitor. It is very hard to electrically output the screen to a monitor if it was not built that way. In the old days Tektronix put cameras on the front of their scopes to capture images, but those days are over. Look at the images of Tektronix camera setups and design your own. Thats would be the easiest fastest and most flexible, but remember the camera flips the image from right to left or left to right ... 0x49

[@TRXLab]

Wayne, what Tom said already is all what can be said on this topic. It is much to complicated to build a converter which would be able to drive a lcd screen.

[@technos123]

Peter nice little upgrade on your power supply. Robert.

[@TRXLab]

Yeah I like it..:-) Thanks for stepping in Robert 73

[@drgnhilord6900]

that won't over heat with the thing having no air circulation around it?

[@TRXLab]

no no problem. enough space for air flow ..

[@ribb4200]

Ah, but how to use M5 since there are only 4 memory buttons?

[@TRXLab]

It is explained in the user manual 73

[@alexrider9476]

Thank you for information about LED and current. I need it.

[@jix177]

Nice job. Thanks for sharing + explaining.

[@TRXLab]

Thanks for watching 73

[@graemebrumfitt6668]

Like it, just bought one of these and think this is a good idea, TFS "thanks for sharing". G :)

[@serwiselektroniki4638]

It's better to read now. I use the same power supply and I have modified heat sink for better and fan for quieter. For low current is inaudible now. Thanks for idea, 73.

[@TRXLab]

Mine seems to be a newer revision. I have heard about the fan issue but it is no problem with my power supply... Thanks for watching Cheers

[@serwiselektroniki4638]

Yes, I saw other heat sink on your version. On my version was thin. Your is newer revision.

[@Roman-ehr]

ELPRO GSM SERWIS ELEKTRONIKI Could you please share your solution how to make a fan quieter?

[@lampmanpaul7459]

Nice video Peter. Thanks.

[@TRXLab]

Thanks for watching 73

[@dinosworkshop6870]

Nice quick fix and video. Thanks

[@TRXLab]

Thanks for watching 73

[@dennisqwertyuiop]

That is a better idea , thank you for information on diodes

[@TRXLab]

Thank you Dennis, yet it is easier to distinguish in the lab..73

[@PelDaddy]

Sometimes you just gotta fix those little annoyances! Thanks.

[@TRXLab]

LOL yeah that is true.. Thanks for watching 73

[@bobclarie]

Thanks again Peter. '73 Bob

[@TRXLab]

Thanks for watching Bob 73

[@bundylovess]

nice job Peter

[@TRXLab]

Again thank you ! 73

[@MrCanidi]

I bought this PSU in 01/2015 at Reichelt Germany and just wanted to make this modification. My LEDs are totally different from yours. Mine have square bodies and the bodies stay flat on the PCB. I made some pictures of my PCB and the modification I made: www.abload.de/gallery.php?key=ynJa52fu I found similar green LEDs at Voelkner Germany (part no. Q38560, manufacturer no. Everlight 583SYGD/S530-E2). These fit very well. My LEDs are driven at 3.3V (HT1117-33) and with 330 Ohms the green LED is to dark. So I replaced the resistor by a 56 Ohm one. The current is about 17 mA what the driver (74HC595D) is able to deliver (up to 20 mA). Now it looks terrific!

[@TRXLab]

Nice picture very well done! It is intriguing that the manufacture is changing the series so quickly...Thanks for the exiting report. 73

[@davidgaleski5303]

thank you good job!

[@TRXLab]

Thanks for watching 73

[@notfallmed]

Danke Peter schönes Wochenende 55 73

[@TRXLab]

Danke fürs vorbeischauen Peter ! Wünsche auch ein schönes Restwochenende.55 73

[@tiromancino_tt]

un video di 15 minuti per aver cambiato colore ad un led ? mah !

[@rrpeck1]

it's this not zhis,not serious in series

[@fredskalski3601]

I continue to "ogle" at your test equipment. I haven't had access to that kind since I retired from my communications job! Ski

[@TRXLab]

Hi Fred, I can understand that you ogle (by the way is that a Slovenian word?) if you had access to such equipment for a lifetime in your job..

[@fredskalski3601]

Hi Peter, Actually "ogle" is a word shown in Webster's Dictionary, and is defined as "an amorous or flirtatious look". Kind of the same.... Yes, 37 years in Michigan State Police Communications gave me access to some wonderful stuff! I used it several times on my Ham equipment.

[@nefton001]

когда собаке делать нечего она яйца лижет