Another great repair. I love to see radios like this being brought back to life instead of being scrapped.

As an Icom ic-706 mk2G owner Your vido was probably the most interesting I have watched for a long time. Thank you.

What a great joy to watch so nicely done and challenging I can't express my deep appreciation to showing me this. I own a 706MKIIG and glad to see the inside of it and learn so much that would be valuable to me if it ever needs repair. You really do the best work, and show the details most leave out which is so helpful. Great repair well worth watching. super thanks till next video

G'day Peter, many thanks for an awesome video. It make you think of the parts we have in our radios and why it burn out. One person gave up and the next bloke repaired it. Thank goodness we have people like Peter.....I am very impressed . Cheers mate.

Like the video, well done, l have been out of Ham Radio for almost 10 years and all l have now is my lcon 706MK2G and when l put it away was working fine, looking to power it up and spend so time with over the winter. Once more nice video.

Great video...can't believe I watched the whole thing, though. My friends would tell me to get a life. But, as a ham operator since age eleven (63 now), and having built my first receiver back then (winding my coils around old tube bases), I found your video very entertaining. And, I love my 706MKIIG. Good job, good narration, and great camera work!

Peter Good to see an electronic engineer at work it is a joy and thank you!

Great repair job on a otherwise dead radio. Not many would tackle that kind of board damage. I work in the 2-way profession and generally that kind of repair is not done. On my own time I have done similar repairs. I like your shop / work bench, plenty of top notch test equipment. I would feel right at home. Just found your KZfaq channel. Keep up the great work and videos - I learn a lot on multi-band radios from you.

Thank you for your videos. I love the way you explain when you show us the schematics, and even a dummy like me can follow you and learn how to read a schematic. Thank you for taking your time to show us this. 73 from LB5JG Norway

Impressive repair, you are very brave to take on someone else incomplete work. Great video, Thank You!

Another excellent video! I thought it was toast when I saw the burnt PCB, great job saving this radio!

I Missed the notification, I'm Late! Great Video Peter! Hey you know what ICOM stands for, I Can Only Monitor. LOL! Thanks for the kind mention.

amazing Peter. I had doubt but again you pulled it off. Thank you for the video

I know a bit late but tnx a lot! I have now exactly the same issue iand it just helped me to trust in my own abilities to understand to circuit. Since then MXR9745T1 became obsolete and ICOM doesnt stock them. For those who need - any small signal N Channel FET, including BIG rd15hvf1 will work but I used original (china) and tested also 2SK with SO-69 package and modified the bias / gain circuitry. Again, tnx a lot 73! OK2IT

Another great video Peter. Thanks for posting these.

Well done ! I learned some things from your video .THANK YOU 73 Bob Michigan USA

Very precise and careful, with attention to detail, thankyou for the excellent video.

Great repair again Peter.. It was good to see that it wasn't a 3 or 4 layer board, or this could have been ready for the trash. Regards my friend John

Excellent diagnosis and work ! I love watching your videos they are relaxing in a way.

I repaired an ICOM 706 MK II G with the same fault and I had driver fault also, very hard to solder it !!!! Thanks Peter. 73s Pasquale IW0HEX

The most common reason for Q121 to blow out is that R122 was often stuffed with a 4.7k resistor instead of 2.2k, which forces the VGS of Q121 to about 4 VOLTS all the time! That makes it dissipate almost 2 watts continuously. The fix is to either pull the board out and change R122 to 2.2k, or, to simply add a 4.7k resistor from the gate of Q121 to ground, which brings the bias down to around 2 volts, and the idle power down to under 200mW. Lowering the power via the menu on the radio will not change the idle power! You can measure the Vg to ground on Q121 to see if your radio has the issue. If you read around 4V, you need to fix it ASAP. So many IC-706MKIIG are just about to fail due to this error. I will post a video shortly on the details, but the fix is simple and can be done by anyone with a little soldering experience. 73 and great video! de W6EL

Yet another very good and interesting video. Always worth an attempt at a repair, keep the repair videos coming. Always fantastic to watch you working.. Karl.

Very I really enjoyed and benefited from the step-by-step description of your troubleshooting technique. 73 de NT5A

Another great presentation of the art,thank you Peter for your very informative videos.

A difficult job nicely done! Also let me congratulate you on your excellent command of the English language.

Peter another fine mess you sorted out the worse thing when someone else has been inside and left a mess for you to repair people would be better to bring them to you to fix instead of trying to fix as they could do more damage and give you extra problems to sort out well done to see an expert at work :)

Coming to this very late in the day! However an excellent description showing how to replace the burnt out pre-driver driver FET Q121 in the the 706mk 2 g. It would have helped me if I'd seen this before same fault occured in my 706 (s/n 16566) after many years of good service I inadvertantly left it on TX for half an hour it failed. After replacing the FET the fault occured again but only after a short period of TX (Q121's relies on the PCB as a heat sink which it seems is less effective if the PCB is burnt) . The problem appears to be due to R122 in the gate bias circuit of Q121 being factory fitted with a 4.7k resistor instead of the correct value as shown in the circuit diagram & parts list as 2.2k . This sets the bias at about 4v instead of 2v. Q121 then draws too much current eventully fails out if left on TX for too long. Other 706 owners have it seems had the same fault. Were only706's from a batch affected or does it apply to all Mk2g's ? I believe that some 703's may have had a similar fault. 73... Ken G3LVP

Hi Peter, that looked a real challenge, you managed to do it, great video and repair...Fred in UK.

Hello Peter nice video interesting job challenge waiting for a other video

I just started watching your videos, your wealth of knowledge is amazing. Your videos are informing. thank you.

Great video and radio. Only problem I've had is VERY intermittent receive being very weak on 2 meter ssb. I think it might also happen on fm, but it's been a long time since I've used this radio on 2 meter fm so I don't remember. It's never been frequent enough to warrant taking it apart and quickly goes away when you quickly key the mike a couple of times. I love the vfd display on the LP-100A. Looks like a nice piece of test equipment. Best regards.

GOOD JOB. Some shops might not try that , but I think it is a good repair and it may last :) Thanks for making and sharing these videos.

What a mess,I admire your tenacity!!

Paul is the reason i found this channel :)

Order out of chaos ......excellent work as always they are all worth saving :)

Great repair - really enjoyed following along. Cheers, John

You got some patience dude. . . One look at that and it would have gone in the trash can if it was me.... Feels good to rescue such a dud though, I have done it, and it feels good.

I tend to remove all scorched pcb material (and then fill up with epoxy to get flush), especially when its near FETs, as the material often comes down to a few MΩ per square or even lower, and the FETs gates often don't like that at all.

Terrific video-Enjoyed very much. Thanks for all the effort..............

Good outcome on a job that many technicians would probably not touch. Burnt PCB, dubious components, evaporated traces. Not a good start! My question would be why that pre-driver FET suddenly went short circuit. Your guess that the 5.6 R was incorrectly labelled was a good one, and if that source resistor had been 5.6k the maximum current through the resistor would have been 2 mA but as it is 5.6R, the current is over 2 amps and power dissipated in the resistor would be almost 30 watts, no wonder things got (too) hot! 73 Andrew VK1DA.

Great repair job! Thanks for all your videos!

Very nice repair Peter- that board was just about a write off! Nice radio though. Yeah I saw that 5.6k on the schematic too and I thought it looked odd! :D

hi all, for anyone who needs the transistors they are the as the pa used on the f3/f3s/f4/f4s/40s hand held radios

This problem ive seen before..i burnt out on of my 706's just like this one but with more severe damage than meant the board was not repairable..burnt boards are sometimes resistive, carbon conducts and worse at RF , so even if the track is at the correct resistance to ground via resistors, it could have serious problems at RF frequencies. one has to ask why the pre driver gets so hot that it burns its tracks and fails in the first place.. ive had 5, 706's and they are great radios, cooling is a major issue, the internal fan mod, that we did even on new radios was to add a resistor to the switchable fan supply ( that increases cooling during transmit ) direct to the 12v supply (13.8v) so that the fan runs a little faster all the time and keeps the radio cooler. I even did a 2nd upgrade to my current radio last year during a heatwave as shack temperatures were so high i decided to increase the air flow.. by reducing the resistor value further to increase fan speed.. this mod is recommended for many small high power radios where cooling is critical. I've repaired boards by inserting a new section having cut out the burnt section and making a copy section from another board , de populated to be able to photocopy and etch a replacement section. not an easy task but its been done with success. having a good section of PCB under the components is necessary to assure sufficient cooling and heat dissipation after the repair. Thicker copper plated boards are better for heat transfer and rebuilding burnt tracks with better boards is recommended. good repair..

Nice job! I was afraid the PCB might be a lost cause. I agree that it is worth trying to save good devices rather than junking them.

Thanks so much for sharing this delicate repair with us. Your knowledge and skill is impressive. Keep up the good work. '73 Bob N7ISU

GREAT REPAIR !!!

This is why you need to know the techs ability before letting them work on your equipment! Great work, great video... de KK4LGL

Thanks for a great repair video

Hi Peter...I think its Peter, most interesting video and good to see you get the radio working. I've just done similar repairs but my damage was much worse!....L232 supplies 13.7 Volts to the VHF/UHF Power FET because this draws 12 Amps at full power it gets pretty hot...its taken over 10 years but just last week this connection into the PCB was slowly breaking down to finally result in a small electrical fire that created a 6 mm hole right through the PCB!....I had to use Solder Wick Braid to replace damage tracks, I've only just placed power on and all seems okay albeit the power appears a little low on VHF. I lost a small ceramic SMT capacitor that sits just under L232 between ground and the Drain of Q231 but its not shown on the parts layout diagram on page 59 of the Service Manual. In your video I could see the capacitor was fitted, I wonder if you might have information that indicates what its value is and or its circuit reference?....CheersClint - VK3CSJMelbourne

Espectacular!!! Very nice and interesting repair. Congratulations!!

Peter , I was hoping to get more info on glueing the copper trace back ? I have looking around to see what others are doing to glue back old , or put in replacement traces ? Thanks for your efforts . John

zer gut ! you are the radio maestro !

Thanks for another fantastic video.

You sir are the master great repair

Wow, Peter, another great video. I cannot imagine you would work on a radio that someone else has butchered. I sure do enjoy your videos--you are a top notch technician and teacher/instructor. Were you aware of the "new" heat sync paste that is available now? It has some kinda metal made into the paste which is supposed to conduct heat much better than the white paste. I just heard about it from another Ham. Cheers & 73 from W Rusty Lane K9POW in eastern Tennessee

Good work sir greedingd from greece 73'

Very good job my friend!

I was looking for specific info , I've been in a lot of trades and can put together lots of things , so I was not looking for general glueing something together . Specifically traces / pads on circuit boards , finding adhesives meant for that purpose , heat resistive extra .

Thank you, yes it was interesting…

hi hope ypour still repairing radios sir i have the old 706mk1 i was useing it on 20 watts when hi keyed up to respond to a call i heard a iss from speaker then sudden problem on receiv on hf 20m everythink works normal just no receive 2m band works with signal as normal thanks im in the uk thankyou

I enjoy watching you repair you are a good teacher . may i please send you a sonyi pro80 to repair for me

Great repair, tnx for sharing... Bud...

I have a question about the 706. I have found that every couple of years of operating in the mobile environment, I have to clean/polish the contact area between the metal case and the leaf-spring grounding strips. Do you recommend leaving these contact areas "dry", or using some type of conductive grease?

Very detailed and interesting!!!

Greetings dear friend. Could you help me to be in the SET MODE ADJUSTMENT of the Icom IC-706 MKIIG? I don't know the type and configuration of the Plug that is connected to the REMOTE to access its Service Menu.

Sir good evening. I am vu2nsk whenever I have time I am watching your video. Now I have one vertex vx7 R .I was put in charge long time the charger was heated and qrt. After I switched on the vx7R nothing happened . I hope it was QRT. SO please let me know what is the problem. Can you give some idea. If I send it to you can you rectify it sir. In India no service person is available.please reply

I enjoy all of your videos, I wish I had some of the equipment on your very well stocked bench! I see you have a rubidium standard on your bench, do you also utilize a GPS locked reference as well? All the best from KC2IRV

excellent video..

Thank you

Your good friend should have brought the radio to you firs!

perfect, nice job and very interested to see. Thanks 73 Ernest pa3dlp

Superb video Mr TRX, I love watching you work as you have lots of patience and dont seem to ever let a problem beat you - Just one question for you and this is when peaking out the transmit on a transmitter do you think an analog meter is easier than you're digital one sometimes? I always prefer analog for peaking as a digital power meter I find a little jumpy! But I suppose its a personal choice? Anyway very interesting videos you make and keep up the great work my friend.......All the best from the U.K......

Realy, realy nice video. Very interesting :)

How does one get in touch with you for repairs, love your videos

Great repair thank you

Good job and thanks for sharing

Hi Paul I have a AOR AR 8200 WIDE RANGE RECEIVER bought the apparently has an error with the S-meter. The S-meter has permanent full scale. The receiver has been disassembled ever to renew the backlight. Did you ever feel like to look over? Perhaps it would be an interesting video on your channel. Lg Jogi from Cologne

Peter I have mk2g that has stopped both to and rx. VHF uhf seems fine. Very poor sensitivity on hf. Only very strong broadcast signals come through. Obviously some parts that are common to tx/rx have gone bad. How do I start troubleshooting ? Before this happened both the tx and rx became intermittent. Thanks. Vu2yk.

Brilliant

good repair

Im seeing way too many icoms failing....makes me like kenwood even more...excellent job on an ugly mess 73s

I wish you had cleared away the charred area of the board before installing the new transistor. The previous person looks to have been defeated by the situation and abandoned it to your care.

Hello TRX bench. I have a Mk2G which became intermittent in both TX and RX. Since about a week now both RX and TX now gone. Looks like a fault in some common line. Can you give me a lead on what could be possible trouble points. Thanks. Rahul.

Hello there, i am looking for ICOM IC-706MK2 VFO Encoder repalcement parts..

can u pls fix my Sony crf-1 ? dispaly doesn't work well for fine tuning thx

Hello , I have same this txrx hf not transmitted and receive but the v/UHF working well , I try to open top cover to see is there burn think , nothing found , but I press PTT on HF the fan is worked , due to no work shop in my country how can you help me ? 73

I have Icom 706 MKIIG for many years, now no TX on SSB. FM is working on TX with full power out. Any clues anyone? Thanks

Many thanks for an awesome video. 73...dk2ndr best regards.

Peter you are a great !!! you an collegue ham-radio ? if yes your call ?

verry good repair. Thanks for share it 73 Marcel notenboom Pa1mar

Well done Peter. 73 de Frank

Hola buenos días, soy Felipe padilla HJ6GPJ -Colombia. Tengo un radio icom IC 706 MKIIG malo. No enciende. Alguna forma de reparlo o un manual de fallas o reparaciones. Muchas gracias Felipe padilla Jaramillo HJ 6 GPJ

those gray coax cables on the circuitboards is it 75ohm or 50ohm?

please help icom ic-7400 TX and RX and PLL / VCO problematic

my ICOM IC-706 MKIIG has zero receive below 2mhz not possible listening to am brodcast radios no signal below 2mhz

Really enjoy your work and video's. W6WUH

hello, do you know why the icom 706 gone deaf in the vhf part, I tried to check all parts and seen to be fine but the manual does not say where to find the vhf troubles. if you know or have a clue I appreciated any info that you could give me. Best Regards jorge

really discouraged with icom. i literally order approx $22,000 a year in gear with the icom name on it ... i order from gigaparts which is excellent... one time i have a problem and icom will not stand behind it .. i order 2 icom 718 radios at a time, one time recently i get a case that is dented, " not the box the case" so i know it happened at icom , i do not blame it on gigaparts, there is no way it happened at gigaparts, it happened at the factory . was told i had to purchase a new case lid for $36.00 .. nice staff at icom but when it comes to customer service i am really truly disappointed. over not making it right they are willing to lose a customer that spends so much money on their product. .amazing......Attn icom. This will be posted in every area of the web i can find to copy and paste..

preciso de uma placa do PA do ICOM 706MKIIG