#187

[@lyntonprescott3412]

Well done again. I wish I had 1% of your knowledge and 10% of your equipment! Fantastic diagnosis and a wonderful repair. You are the Mr Carlson of Germany! Lynton

[@TRXLab]

to much the honer...Thank you

[@bigmac965]

Peter, I was discouraged when you were talking of having to replace the entire display, but I must say I got very excited when I saw the panel light up with your tester, and then again when it worked after the repair! Peter saves the day again! Thanks for your efforts in making these videos! I learn something every time.

[@TRXLab]

LOL yeah all turned out good :-) Thanks for watching 73

[@laser-on-off]

It is always a pleasure to watch your videos. Thanks a lot, that was a difficult one.

[@TRXLab]

Thank you for the kind feed-back

[@TheRadioShop]

That tester is really a nice piece to have in the shop Peter. Good job at troubleshooting this unit. Big thumbs up 73

[@TRXLab]

Yes the test is really of great help. Thanks for stepping in my friend 73

[@cwebs1000]

Love it when you say "Lets CRACK IT OPEN". I know that means we are going to work. Great work. Carl

[@TRXLab]

LOL yeah ...Thanks for watching

[@lylewatts6370]

Wow great troubleshooting skills and thanks for showing us that any problem big or small can be repaired. That is a nice radio.

[@TRXLab]

Thanks for watching

[@masterfranco01]

Congratulations with this repair Peter. Thanks again for sharing.

[@TRXLab]

Thank you Franco

[@robertcalkjr.8325]

Thanks Peter. I was pulling my hair out waiting for you to use the "inexpensive" CCFL tester. lol Thanks for showing us the CCFL tube, though I know that you didn't have to take it apart to troubleshoot this radio!

[@TRXLab]

LOL yeah that happens when you have awarded your tools to a friend for a computer monitor repair. But additional to that I wanted to show how a CCFL looks like. Thanks for watching Robert

[@iw0hex]

Hi Peter, many years ago (2010) I had an IC-7700 with faulty display but in my case unluckily CCFL was faulty . I had to buy a new display to fix my radio, very expansive at that time. For your information, IC-7700 and IC-7800 use the same display. Thanks for sharing this interesting video, my dear friend. Best 73s de IW0HEX Pasquale.

[@TRXLab]

Hi Pasquale, and all that is happening while Icom is stating there are no issues with the CCFL's LOL and still they don't supply CCFL's really unbelievable.. Thanks for info and comment my friend 73

[@HamRadioTV]

Nice Job! Thanks for taking the time to show all of us!

[@TRXLab]

Thanks for watching 73

[@DonDegidio]

Hi Peter, That CCFL tester just paid for itself finding the display tube was OK. Seems an easy repair once the transformer was determined faulty. 73 WB3BJU

[@TRXLab]

Sure the CCFL tester is of great help! Thanks for watching Donald 73

[@michaelclutton8446]

Nice repair Peter, it's great how you work. Certainly work in a logical way and make it look easy. I know it's not.

[@TRXLab]

Thank you Michael. Yes you are right it is a logical way to follow but sometimes not easy to find :^)

[@hancecrawford]

very complicated fault to find you were very lucky to get spare parts, it is very difficult to get back light for this radio it was a good job you had an CCFL tester or you would have been up the creek without a paddle and that CCFL more or less paid for its self another success peter well done :)

[@TRXLab]

Thank you John, yeah it was a bit tricky and it was good to have the CCFL tester. Radio is back working and that is what count :^) 73

[@MrKelendros]

Nice work and video peter as always, a pleasure watching your videos.

[@TRXLab]

Thank you Carlos

[@garybevis8691]

Hi Peter, very good job to repair the CCFL backlight. That is a very nice little device for testing the CCFL. I found one on eBay for just under 50 USD! That thing would pay for itself quickly. It can be so frustrating to not know which is the defect part when either one could be cause. Without the proper test equipment or diagnostic procedure it can be maddening. ...:-) Thanks and 73's KI7TWX

[@TRXLab]

Thanks for comment Garry. Oh the price must have been dropped some time ago I paid more for it.. 73

[@SteveMasonCanada]

Another great video! Having repaired over 100 LCD computer monitors in the last few years, I was thinking there's no way it's the CCFL tube. In my experience with monitors, it's about 80% caps, 12% transistors 7% transformers and 1% tubes. I was leaning toward the transformer due to the fact that the caps didn't look like they were in a hot environment.

[@TRXLab]

Fully agree with your split but I tended a bit to the CCFL as the circuit seemed to be fine after the first test. Thanks for watching Steve

[@user-uv4xe3cq2y]

Thanks for another great video, Peter!

[@g0fvt]

Hi Peter, I am late to finding this video, the 7400/746 Pro and the 756 Pro use a very near identical inverter circuit. I believe the transformer is a rare failure and that the issue is usually around the "dimmer" transistor or the 2 electrolytics. I am gathering up the enthusiasm to fix mine, the radio was given to me with the display not lighting, but it did burst into life for a few days before going off again. I may try just replacing the capacitors to see if that is the issue, high ESR. 73

[@CT1JRZ]

Great job Peter! That one was a dificult one.

[@TRXLab]

Thank you ! 73

[@nr3rful]

You are an electronics guru.

[@Swataia]

Nice job! And for everybody's information one can find now L I U shaped CCFL tubes for different display sizes from google. And those are not even expensive. There will be time when those need to be replaced also. Or then changed with a LED stripe. But anyway, don't panic if your radios backlight goes dark, we have hope!

[@stevec5000]

You don't need a special tester to check CCFL lamps. I picked up a lamp at the store that has a CCFL tube shaped like a Christmas tree and took it apart so I can check tubes with the power supply and use the Christmas tree tube to check power supplies in radios, laptops and other devices. If it was my radio I'd replace the CCFL tube with a strip of LED's though.

[@TRXLab]

You are right Steve. We have a saying here > Many ways leading to Rome :-)

[@robertcalkjr.8325]

Yeah, but the testers are not very expensive, even for LED strip testers. I have both.

[@ovnibus_cx3cp]

hi Peter, I think there was no need to disassemble the display unit to reach the CFLH lamp, I think the first thing should have been to analyze if the flayback circuit did oscillate. You could have used the oscilloscope to determine that earlier. The amplitude of the oscillation of the cold side could be seen, in the collectors of Q201 and Q202.

[@rscelectrical7091]

Very nice job as usual Peter, CCFL faults can be a total pain in the neck.

[@TRXLab]

Thank you ! Yes 100% agreed can be a pain!

[@markkut9419]

Quite like same fault was IC-746Pro but only need change CFL power supply transistor. Thank you this video.

[@coltronex]

Superb fix,well done to you!!!

[@TRXLab]

Thanks for feed back 73

[@wayneeves3874]

Absolutely fantastic!

[@mikaelkarlsson9945]

Why didn't you try the CCFL with the tester first before risking damage the LCD by opening it?

[@TRXLab]

Well for minimum 98% you do not need any tools as issues in a back light circuit are obvious...

[@repairfreak]

Had no display issue with 60” flatscreen Television. Using flashlight reveals lcd board was producing picture as your transceiver was . In this case it was not the power supply. It was a bad led on one of the many led backlight strips that are in series that was bad. I used a led tester made by same manufacture to test leds safety. I would like to get a ccfl tester like yours for some older and smaller monitors still utilize ccfl (cold cathode florescent) tubes. Another nice video TRX Bench. 👍👍

[@kg2ix]

Very interesting video. I knew you would figure it out. Thank you Peter, once again for teaching me something I was not familiar with. 73, kg2ix

[@TRXLab]

Thanks for feed-back glad that you liked it! 73

[@paul-c7541]

Wow Peter , that was a tough dog of a job

[@TRXLab]

Thank you Paul, yes no obvious signs of a fault and that is already very seldom with CCFL issues.. Thanks for comment 73

[@hernanirodrigues5261]

Very nice job ! many thanks to shered with everybody!

[@charliem.9998]

Deine Videos sind wirklich ganz toll gemacht! Ein Mann mit absoluten Fachverstand!! Ich genieße jedes Video von Dir!! herzliche 73 de DL6RDE / AA1KD, Charlie

[@TRXLab]

Vielen Dank, freut mich das dir meine Videos gfallen Charlie...! 73

[@charliem.9998]

@@TRXLab ja, sind wirklich topp ... Dein Wissen hätte ich gerne ... 73 de DL6RDE

[@oe5pop320]

Einen schönen guten Abend! Ich hab eine Frage bitte. Wäre sehr nett wenn du mir kurz was dazu sagen könntest. Ich möchte gerne die Clock Batterie bei dem IC 7700 wechseln. Im Manual steht das auch beschrieben wie das geht. Nur komme ich da sehr schlecht dazu. Ich müsste wohl die Abdeckung vom Display - Port entfernen. Geht das anders auch? Danke und Besten Gruß

[@GeorgeEI7KO]

Good job Peter. That was a tricky buggar. 73

[@TRXLab]

Thank you George! 73

[@ojjenkins7110]

Nice fix Peter. I wonder if the IC-7300, 7610, and the 9700 have went to leds???? If not they should.

[@TRXLab]

Thank you OJ. Not entirely sure I believe they still use CCFL

[@bundylovess]

Nice job peter Big thumbs up 👍

[@TRXLab]

Thank you Allan 73

[@bblod4896]

I wonder if there is an LED replacement tube available. You could bypass the high voltage circuit. Great diagnostic video.

[@TRXLab]

You always can do a led conversion but this time it would have been more expensive as it is very time consuming..

[@TheSblackwater]

What service manual is that? I have S-14407XZ-C1 Feb 2008 and the schematic for the Display board doesn't appear to be there.

[@TheSblackwater]

Never mind I found it. It's in the scematic for the "front unit". Thanks

[@TRXLab]

very good ;.)

[@boxingday11]

Thank you Peter for your film. Carl.

[@TRXLab]

Thank you Carl

[@NoName-mr1lh]

That was another great repair video. Thanks! Do you have any tips on where to find old and discontinued line output transformers used for driving the CRT in old test equipment?

[@jonka1]

You could try rewinding them. I have done this in old tvs.

[@NoName-mr1lh]

@@jonka1, I did consider that but if the coils are encapsulated, is it possible to remove the coils without damaging them? Im not certain yet that the transformer is the problem so I have more checks to do, possibly removing the transformer from the PCB. First I'll try replacing the TDA1170S IC. I'm trying to fix a Marconi Instruments 2295D. It is a vertical scan system and the vertical switching transistor was replaced by the previous owner but this didn't fix the problem. This is equivalent to the Horizontal Output Transistor in a TV.

[@jonka1]

In the case of an encapulated coil I am not sure if it's possible to fix it. I recommend you google "ring test" of transformers. This often gives a good idea if there are any internal shorted turns which are common in lopts. It's possible (and I do this) to use the square wave calibrator output on an analogue scope as a driver. Connect the primary to it and scope the overwind to look for the ringing response.

[@NoName-mr1lh]

@@jonka1, thanks for the advice I'll give it a try when I get the transformer out if I can't find any other problems. I did find an amateur radio website on the internet that sells them for my radio test set but have not had a reply yet. I'm determined to bring it back to life.

[@jonka1]

www.vintage-radio.net/forum/ Try looking here. I'm a member and I think you will receive help and advice from some of the members. You can even add your repairs to the list of posts.

[@assistenciatecnicaemmicrof8817]

Hi Peter , CCFL has its flaws mainly due to the wear of the lamps, today it would be more efficient to upgrade to led and in the control circuit of the same brightness a control by pwm, just a humble idea....73 !!

[@TRXLab]

Yes you are 100% right CCFL's loosing luminosity after a while and they go faulty as well. If a led conversion is less pricey (and that is the combination of time and material) it always makes sense. 73

[@OleF112]

Great job on a big radio. CCFL never was a economic and reliable choice to do backlightning, but a dozen of years ago it was the only choice to get a bright light behind LCD. I dont know the age of the Icom exactly, but i guess CCFL was already an old option and LED were available then. My two cents...Nevertheless your repair was great. That was about two levels about my patience ;-) 73 de Olaf

[@TRXLab]

Yes I agree but I believe for the manufactures it must be somewhat less pricey to use CCFL..They would not use it if they don't have a benefit . Thanks for watching

[@FUNKLABOR_DL1LEP]

Great work!

[@13EL121]

👍👍👍👍👍👍👍👍👍 mehr kann ich nicht dazu sagen. Tolles Video Peter! Wie eigentlich immer...aber das war wirklich eine harte Nuss.😉

[@TRXLab]

vielen Dank für die freundlichen Worte!

[@John_Smith__]

Great video once again. Just a very late suggestion, maybe a dumb one in this case. Sometimes those coils have inside the plastic wrapping a PTC to protect them ... I have to be honest since this is not my field, but I've seen many on smps's from solder irons to multimeters to all kinds of electronic gear. I know it's too late now but the transformer PTC protection could have been the cause of the problem.

[@TRXLab]

You are not wrong John but I have never found a PTC in a ccfl transformer. Thanks for comment

[@John_Smith__]

@@TRXLab Thanks for the heads up reply ... and I'm more of a zero«s and one's person, but I truly enjoy your channel. Now another thing I would like to ask someone like you an expert in radios ... why not make a review/evaluation of the very inexpensive radios like the Baofeng UV-5R handheld type. Those are usually very very inexpensive ... 25$ from China direct to home, and they are a very very good start for kids and almost everyone that wants to begin radio-amateur activities. It is truly a simple suggestion for your channel, but I think it would be a good think to promote on future radio-amateur fans :)

[@frankthetank3342]

I'm about to perform an LED upgrade to an Icom 756 pro3.

[@bfx8185]

I'm wondering why you took apart display assembly and didn't use your CCFL tester at the beginning:) And try to check Q factor of primary side of this transformer.

[@rlmillr]

Suspecting an ebay order for CCFL tester around 25:00 :)

[@TRXLab]

LOL yes my CCFL tester is from China and it took 8 weeks for shipping some time ago. Do you really believe that a ham radio operator would like to wait for that long time :-)

[@TRXLab]

LOL yeah that happens when you have awarded your tools to a friend for a computer monitor repair.

[@borayurt66]

Another great repair job well done. This was not an easy one. I wonder why you ordered and changed everything in that high voltage section. This is the first time I see you change a part without making sure that it is broken first. And why did you leave one of the power transistors?

[@TRXLab]

Yes you are right but especially components in circuits like this are sometimes tricky to test. Thus it is a good idea to swap all rather not to have a warranty issue later.

[@gvvq-pi5ml]

Hi Peter, great video, i just wondered on some of these new radios you can plug in an external supply, for people with poor eyes...might have seen it work with that from Fred g4vvq. Uk.

[@gvvq-pi5ml]

I meant to say an external Monitor

[@TRXLab]

Hi Fred, yes you are absolutely right there is a connector for an external monitor which would bring back the usability but for service purposes it would not tell if the internal display is still alive..

[@Bob_Kay]

Hi Peter, your videos are very helpful and informative, thank you. I know you're busy but please tell me what camera you are using for your close up pictures. My eyes are getting weak and I'm having difficulty seeing small stuff. Thank you.

[@TRXLab]

Hi my camera is a Sony HDR-CX240. Thanks for watching my videos.

[@capt.mike73ahoy14]

That was an excellent tutorial Pete. Thanks for producing it. FYI...there is a Canadian ham who has been selling complete display boards for the Icom Pro series II & III. He is on the Icom 756 Pro 3 users group should you have any interest in that part. 73 & Good DX OM! Mike W4DL.

[@TRXLab]

Thank you Mike. Yes I have seen some led conversions and that is always the lifeline if nothing else helps.. Thanks for comment 73

[@Elektronika_Samodelki_Remont]

Супер! Успехов и Здоровья, Вам!💎💎💎💎💎

[@ottomanfred2473]

Help, I have a icom 707 radio that has a blank LCD screen. I was wondering if anyone has any experience with this problem and were can I get a replacement screen. Trying to save this radio. Thanks.

[@berndb.5097]

Again and again the old problem with the CFL backlights. I call that "ICOM diving" :-P Good job, Peter ..... For that you really need a steady hand. But, I think (and see), it´s no problem for you :-)

[@TRXLab]

Hi Bernd, most funny is that Icom is stating that there are never issues with the CCFL.. Thanks for watching 73

[@TheDefpom]

I’m surprised it isn’t an electroluminescent backlight.

[@TRXLab]

Yeah I agree that was my first assumption when I started this job.

[@mrquick1937]

Holy crap you are good!!! Thanks again for a great lesson. How do u remember where everything goes after completing the repair? Amazing!

[@TRXLab]

Thanks. Today it is easy as you only need to take some photos. Years back we need to draw it by hand..73

[@JamesP6084]

Peter did you not have the Tester in the beginning or did you get it later ?

[@TRXLab]

I bought mine quite a time ago but the tester was awarded to friend for a computer monitor repair. Since 98% of back light issues are obvious I didn't think to need the tester . Thanks for watching James!

[@dennisqwertyuiop]

great repair

[@TRXLab]

Thank you Dennis

[@johndk9jc354]

Hast du die ausgebauten Teile nicht mehr getestet? Kam der Trafo von ICOM oder ist das ein Standard Bauteil?

[@TRXLab]

Natürlich habe ich die Bauteile alle gestestet und nur der Trafo hatte andere Primärwerte als der Neue. Somit ist bewiesen das wir einen Primärschluss hatten. Der Trafo kam von Icom.

[@johndk9jc354]

@@TRXLab Super Info, danke für dein Feedback.

[@phildavies5833]

Green LED for RX and power on missing?

[@TRXLab]

Wow eagle eyes :-) Yes an additional transistor to swap in the psu.

[@gvvq-pi5ml]

es sorry i meant to say an External Display unit, like a small tv from Fred. g4vvq.

[@hdmalpas]

Nice one Peter. M3KQW 73s

[@TRXLab]

Thank you Howard 73

[@danabland9928]

How much did that repair cost with parts Sir? p.s love your vids.

[@markkut9419]

I had ICOM IC-746pro where display dim I have new CFL tube but i already known it not faulty So examination CFL power supply and there's is power transistor faulty due lack of thermal dissipation I find another tr and changed it, success, works again Very rarely CFL tunbe faulty

[@gueremaxflavien3482]

Hello I need help in an emergency, I have turned on the ICOM HF / 50MHZ TRANSCEIVER IC-77000 and the reception is better, except that I can no longer transmit someone can help me If he Please.

[@hieristderkanalvomyoutuber5387]

Hat das Gerät eine oder zwei Speicher Batterien? Manchmal ist es Besser die 2032 Durch Größere Akkus und Ladegerät zersetzen. ZB. 3V 2800mA Dann Benötigt man keinen Stenby Strom und Das Funkgerät Kann Viel Jahre die Abgelegten Daten Erhalten bei Transport Lagerraum Aufbewahrung usw. Bei Einigen Geräten ist das sinnvoll Da man Später Sonst Alle Daten wieder Neu Programmieren müsste wenn die Batterie unerwartet ohne Vorwarnung Bei 2.x Volt Die Daten verliert. Platz ist ja im Gerät genügend vorhanden. Beim Austausch gibt es mehrere Möglichkeiten um die Datensätze beim Austausch zu Erhalten. 1. Der Strom Kommt Parallel auch vom Gerät um Die Batterie zu messen und zu unterstützen. Dann kann bei Eingeschaltetem Gerät Die Batterie getauscht werden. 2. Wenn der Strom nur von der Batterie für den RAM kommt ist eine Separate Stromquelle Parallel vorweg vor zu Legen. Dann der Speicher bzw. RAM immer 3V Hatt. Li-ion 3.7V Akku / Sicherung / Widerstand (RX) und Ledautomatik. 😉 Schön das Die Display Kaltkathoden Lampen sind nicht teuer. Die Größe des Inverters richtet sich nach der Länge der Kathode. Preis liegt so bei 10 €$. Schade das deine Videos nicht in Beiden Sprachen Englisch + Deutsch Gesendet werden. 🙂😉🌐

[@bobs152]

Wow, great video.

[@TRXLab]

Thank you Bob

[@glenngoodale1709]

Nice work and video

[@TRXLab]

Thank you Glenn

[@Beretta96Dan]

Hello, Peter! As an electrician, I know that CFL means compact fluorescent light. Now I'm curious what the first C in CCFL stands for? Always love your videos! 74...Dan w4mnc

[@1967deek]

it means cold cathode fluorescent lamp

[@paultams54]

Google is your friend... cold cathode fluorescent lamp

[@TRXLab]

All the right answers are already give Dan.. Thanks for watching 73

[@TheMrDrMs]

Next, fix the 7610 screen troubles that even icom cannot seem to resolve (bad supplier) LOL!

[@denismatte8727]

big job good job

[@TRXLab]

Thank you Denis 73

[@charlieoscar09]

Icom seem to have problems with these big screens...i remember the 756 pro's having issues with their screens so the issue goes back a good few years...wouldnt want a radio with a screen like this.

[@TRXLab]

You are right and back then ICOM was not able or willing to supply spare parts for those displays.

[@Bass.Player]

Nice job! K5AZE

[@TRXLab]

Thank you! 73