Oh no, another golden screwdriver. It's amazing that you find so many mistakes by other technicians. It finally dawned on me what you were doing pulling the 5 volts to ground to switch the processor to low. Another great repair on an old radio. You saved another one from the scrap pile. W Rusty Lane K9POW in eastern Tennessee

Very nice repair Peter. Thanks for sharing it with us.

Thank god you came back! You are an asset to youtube. Great video, we love you.

@TRXLab

2 жыл бұрын

Thank you for the kind words!

A great surprise to see again a video from you peter. As valuable and instructive as always. Great repair, thx very much for sharing with us a bit of your knowledge.

Nice to see a radio back in service. You do great work my friend! 73, KU4UV

And a big " welcome back " to you as well Peter

I've always liked these older radios nice to see you were able to keep it going. Those smd caps seem like they go bad faster than others. Great job at always. Thanks for sharing stay safe 73

@TRXLab

2 жыл бұрын

Yeah smd lytics from back then are a nightmare

Another great job done, Thank you so much for sharing as I have learnt a lot from your videos and your excellent explanations.

Danke Peter. Wieder sehr informativ. Habe auch so ein TRX. Bei Bedarf weiß ich jetzt wo ich als erstes hinschaue. 73

@TRXLab

2 жыл бұрын

freut mich das es hilfreich war! Danke

Hi ,its wonderful joob, Best regards from Poland.

Great work Peter!

I have been an electronics hobbyist for almost 40 years now and I've learnt about the existence of the LR variant of the 7805 regulator today. Close up shot @8:26, I said "hey! that 7805 has 5 pins?" then I looked it up and found out it has a built in delay function, especially intended for MCU power off/on reset delay. Really neat feature, I must get me some of these. :-) I should have suspected this when we saw the perfect up curve (or no curve) of the reset signal on the scope, you can't get that with a capacitor alone.

Thanks for another great video! May be once I will find a reason of the white noise from the speaker when my TM-742 squelch turned on...

That was a lot of troubleshooting Peter. Great job on getting it back up and running. As always thanks for the video. 73

@TRXLab

2 жыл бұрын

Thank you my friend! Take care! 73

Thanks for the video Petewr, that was a tough one

Thanks for the video another good save.

Yay, my Saturday fix!!! Thanks Peter

Great job as always. Very sound trouble shooting. Very few Tech's out there will spend the time required to bring rigs back to life. Capacitors change value with time and eventually leak. I haven't bought anything used in years because of that fact. Besides used gear is way over priced anyway. I can't see to repair little components anymore. Thanks and you do great work. 73 and have a blessed day. 73 Earnest K5EWM.

Nice work that come to end peter . I have the same radio ,I have it almost for a year now in my schack ,I bought it as a second hand .so far it works ok

Wow Peter. What a great repair. Thank you for the video. Your video quality is very good also. W5DN

Thank you for another fine video,, I felt like I was right there working on it also !!

Great video Peter. I always learn and enjoy your step by step process with explanation!!. I have a suggestion for a future video. I would love to know exactly how to connect a analog scope and rf generator to sweep a band pass filter. Xand Y channels . I sure lots of people would love to see it. Thanks.

Perfect for a Saturday morning! Great job. Thanks Peter. 73de kb7ici

Have a nice sunday,, Peter. Such a nice TRX, look at this design and so simple to use and set. Beside those aging problemes those were such beauties! I am glad that this radio is back in service, and you did a nice job. SMT caps are so nice for replacing those shitty smd alu cans, especially when there ist not much space to solder the small pins. Once again it wa a pleasure for me, Peter. Bleib gesund und 73 nach HE ! Olaf

@TRXLab

2 жыл бұрын

Ja Olaf, das ist wirklich ein schönes Gerät aber es wird alt...Bleib gesund alles Gute

good job. Capacitors almost always the problem.

nice work

Good solid fault finding as usual 👍

nice job!!!! that was some troubleshooting skills.... if it were me i would have to walk away from it several times already...

Super Video, wie immer! Grüße, Sebastian

@TRXLab

2 жыл бұрын

Danke Sebastian! Kommst du mit der Gestaltung deines Labs weiter??

@BalticLab

2 жыл бұрын

@@TRXLab Ja, ist gerade alles in der Umsetzung. Gibt bald wieder Videos.

@TRXLab

2 жыл бұрын

@@BalticLab ah super das freut mich

Peter, I started using the SMD electrolitic capacitor removal technique described by mr. Carlson. I grab them with pliers and twist them off the board. The pads stay attached and the caps go. I had to recap two ICF 7600 with 24 SMD caps each. Not to mention how crowded everything was, I would still be replacing today

@borayurt66

2 жыл бұрын

That method works perfectly in preventive maintenance. That means replacing the caps before they leak acid on the board. But if they did leak acid, the pads may be very corroded and became very weak because of that, any kind of mechanical force (like twisting the cap with pliers) can break and lift the already very weak pad. I would prefer the gentlest approach if I see any level of corrosion on SMD pads. But you are right if the board is crowded and it is not possible to touch the pads of the individual caps without burning something else.

@OctavMandru

2 жыл бұрын

@@borayurt66 Well, I was suspicious first but it worked for one board where pads were attacked badly and I can testify no pad got ripped due to twisting. Only the caps legs got ripped and stuck on the pads.

Perhaps the description meant: No "fire" when powered up😂😂😂 Okay, bad dad joke. Thanks for the video, have a good weekend Peter.

@TRXLab

2 жыл бұрын

LOL yeah

I had a 241 for a while.. very interesting faults.

Hello Peter .I hope you be good . I have a problem where is the band of the 1.2 giga on the tm 742 on the display normally? When I bought the radio was in left side when the radio don't work I send it to repair the radio did fire up the technician repair good but the 1.2 giga went at the right side of the display and the exit of the antenna cable are confused at the option is the 144band at the 144band is the 430band and the 440 band is the 1.2 band .why do this happening ,do you have any idea why this happen ? Do the radio will do link as old condition, i am afraid don't confused the antennas and make a problem . Of course I have see photos in internet some radios have the giga at right some radios at left side and I more confused.

What is the brand of FLUX and solder are you using as your soldering iron tip is always looking clean and bright in all the video I have watched you servicing

💪

251 a Kenwood!

Hello Peter, can you tell me if the front of the TM-742 also works on the TM-741 or is there any difference, thank you in advance. Antonio - Sao Paulo Brazil.

That’s my current mobile radio, great for simplex. Lots of videos on my KZread channel.

Hello, i have same issue with my TM742E. Unfortunately i live in germany and my eyes are not sharp enough to handle SMD. Where i can ask for this repair? The RTX isn´t cheated anyway except band expansion.

Did you keep the green wire connected or figure out the switch issue? If the green wire is still connected doesn't that interfere with using the front panel remotely?

@TRXLab

2 жыл бұрын

Yes the green wire is still there. working fine

ich liebe es . . .

Can you specify the cap values? I have one of these radios that i inherited and I suspect the same fault in the caps, although the board looks clean. The delay pin on the 78LR05 is at 2.4 volts give or take. The regulator is working great, perfect 5v but I think the delay pin is holding the processor down. I have 8 V on pin 1, 2.4v on pin 2, pin 3 gnd, pin 4 is liek something below one volt, pin 6 is 5v.

@KD9BUX_MAKES

2 жыл бұрын

i cant read the dang schematic. I want to order suitable caps.

Normally the 1.2 giga it must be an the option exit? Isn't it write? And the giga i see the cable is gray color.i think the technician mess it a little bit??

Hello Peter. I always learn from your videos. I curious on what type of flux you use. RA? RMA?

@TRXLab

2 жыл бұрын

amtech nc-559-v2-tf tacky flux

@Joe_KS1I

2 жыл бұрын

@@TRXLab Thanks

@Joe_KS1I

2 жыл бұрын

@@TRXLab Are you using 63/37 or 60/40 solder? I have a hard time using lead free solder. I don't like lead free. I always use 60/40 or 63/37.

Where are you located ?

Thanks for this video. I love that radio and have some of them lying around with different problems. But now I have hope that sometimes I will find the time to open them I will find the same bad boys like you. If you need a better copy of the schematic, please let me know. 73 de DG3ACM

@TRXLab

2 жыл бұрын

Danke! Was mir wirklich fehlt sind gute PCB lay outs...

@Curare0202

2 жыл бұрын

@@TRXLab ich schreib dann mal ne Mail.

@DG3ACM-Marc

2 жыл бұрын

@@TRXLab Ich hab geschrieben aber noch keine Antwort bekommen. Falls wirklich Interesse besteht, dann bitte an DG3ACM bei GMX Deutschland schreiben. 73

one on ebay for 1900 bucks. These came out in 1998. Not sure I would feel good about buying it.

@matt9c1

2 жыл бұрын

There's a scam artist selling these on EBay for $1000+ claiming they will do everything including wash your car. These radios will NEVER be worth $1000.

@ke4est

2 жыл бұрын

@@matt9c1 WOW, just read through that. That guy has no clue. Free phone calls all over the world. haha

@TRXLab

2 жыл бұрын

no way wasted money!