#147

Fixing a nice little vintage radio.

[@josephxuereb811]

always appreciate the way you explain things , it might have been a simple fix, its the way you go about chasing the problem and explaining on the schematic drawing tnx agn ...

[@TRXLab]

Thanks for the feed-back Joseph 73

[@dennisqwertyuiop]

another great repair, I need those easy finds thank you for working hard to show and make video

[@TRXLab]

Thank you Dennis, always a pleasure doing videos for an audience like you! 73

[@andreaghilardi1069]

Thank to your video I could repair a friend's ft-747gx and put him again on the air after many years, many are returning to he thobby these days at home.

[@TheRadioShop]

Nice simple fix Peter. Thanks for taking us along with you on the repair. Also thanks for sowing that modification. I need to do that to my 747. 73

[@TRXLab]

Thank you my friend, Yeah it is funny with the filter board in some radios you never have a problem but more than the other half needs this mod...73

[@charlieoscar09]

Thanks for the video Peter very well explained again.....really like the 747GX nice simple reliable radio.

[@TRXLab]

Thanks for watching! Yes it is a nice little vintage radio....73

[@PapasDino]

Always look forward to the weekend and a new TRX Bench video! TNX Peter!

[@TRXLab]

Always a pleasure to create videos for an audience like you Dino!! 73

[@johngulliver6151]

Nice easy fix for you Peter thanks for sharing with us

[@TRXLab]

Thanks for watching John! 73

[@OrbiterElectronics]

I think we possibly knew what the joint issue was before you did here Peter, as the close-up camera shot at 9:48 showed it very well. We could see the antenna wire moving up and down through the hole in the PCB :) Good fix my friend. Cheers, John

[@TRXLab]

LOL yeah you are right John. I have seen it during editing the video but I was not able to see it sitting in front of the radio. You big screen makes the difference :^) Thanks for watching my friend Cheers

[@carloss1476]

Dear Peter, thank you for your detailed explanation about FT747GX's filter board fault. Best regards from Spain.

[@TRXLab]

You are welcome Carlos, thanks for watching and best wishes to Spain! 73

[@mikesradiorepair]

Nice easy repair. Thanks for sharing Peter.

[@TRXLab]

Thanks for watching Mike! 73

[@majordisappointment8692]

Nice fix i am really glad one of those ft-747 came across your bench i will look for that filter fix and see if it has been done. thanks again

[@TRXLab]

glad that was helpful for you! Thanks for feed-back 73

[@lyntonprescott3412]

Great stuff. Well spotted.73’s

[@TeologiaArtesanal]

I fill my self so satisfed watching bad contacts being fixed.

[@GeorgeEI7KO]

A nice handy fix Peter. Dry joints a big problem in a lot of that older stuff. We affectionately refer to the 747 in this part of the world as the 'plastic lunchbox'. Nice easy mod on the filter board also. 73

[@TRXLab]

LOL yeah we call it " plasticbomber" Thanks for stepping in 73

[@rscelectrical7091]

Excellent video as usual Peter, don't see classic dry joints like that too often nowadays. It's usually more subtle.

[@TRXLab]

Thanks for feed-back..73

[@SignalViewRadios]

Another great video!

[@TRXLab]

Thank you Santos 73

[@robertcalkjr.8325]

Nice work, Peter. Thanks.

[@TRXLab]

Thanks for watching my videos Robert. 73

[@berndb.5097]

Hi Peter, Well repaired. This error has already occurred to me very often. I always fix it with very flexible braid. Wire as used, for example, as a measuring cable. Thanks for the entertaining video. :-) 73 Bernd

[@TRXLab]

Hi Bernd, yeah to fix it with most flexible braid is of course the best you can do... Thanks for comment 73

[@PRRGG1]

I had the same problem on the RF filter board with my 747. I repaired the connection and that fixed most of the issues. I did NOT know about the diode problem, I will now fix that next chance I get.

[@Magic3DEnginering]

I just need to say to you big thank you. Thanx to yours tutorial movies i fixed coupple of radios . Big thank you. 73 M0ADM

[@TRXLab]

glad that my videos are of any help....Thanks for feed back 73

[@ojjenkins7110]

AS YOU WERE JIGGLING THE SO-239 I SAW THE WIRE MOVING AS WELL IN THE HOLE OF THE PCB. THOSE FIXES I LIKE ALSO :-) LOVE YOUR VIDEOS :-) ALWAYS LOOK FORWARD TO THE NEW ONES. KØOJ

[@TRXLab]

LOL yeah your big screen made the difference. I did not see it sitting in front of the radio! Thanks for watching 73

[@FrancescoCicarilli]

Hallo! I actually use this nice radio! Very clear explanation! Many thanks

[@fey4949]

Nice repair Peter. Always a pleasure to a specialist at work. Everything looks so simple. This time it was. Maybe a intermodulation test was usefull to confince the OM that output power is not only important thing. I am very curious wat it is. Entertain and learn. Thanks Peter and let the video's come.

[@TRXLab]

You are right as more you push such a little radio for power all the figurers are going worse... Thanks for watching 73

[@livelongandprosper70]

very good thank you

[@sz42781]

Hi I have a yeasu 747gx. The recive is off about 3 kHz, any idea how I would go about repairing this problem?

[@dalebrooks2396]

Peter, I think troubleshooting electronic devices starts out seeming difficult and once you locate the problem they reclassify to easy problems. I was working on an old boat anchor collins and I spent days on end trying to find out why the receiver level would dropout and return. and It turned out to be a notch filter can had a loose connection on a tuned circuit. Now knowing what the problem was it became a simple matter of soldering a connection back on a coil. But intermittent problems can be a nightmare until you find the problem that is hidden. Good job on the video Peter looking forward to the next one.

[@TRXLab]

Yeah that is how it goes some times..Thanks for comment. 73

[@kn9ioutom]

MINE WAS INTRMITTENT ! IT WAS A BAD CONNECTION ON THE ANTENNA COAX CONNECTOR ! I HAD TO OPEN THE PA BOX !

[@adnanmalik7364]

Wow very nice !!! Keep going mate you are doing great job for us !!! U remember i requested u for ICOM A110 VHF radio repair? If you could do it then it will be great !!!

[@TRXLab]

Thank you Adnan. Sorry I'm totally booked out.. 73

[@hancecrawford]

TRX Bench very interesting but as you say know two faults are the same, we are always learning!

[@TRXLab]

Thanks for watching John 73

Hi, I made the second repair (soldering on filter unit) and intermittion of my 747 ended. Thanks!

[@TRXLab]

Glad that it worked for you 73

[@adekdzaki2290]

Greetings, I have an 80 Charly Yeasu radio that I use first, I have to heat it up for 1 hour, then it can transmit and the power goes out, if not it doesn't work,Please help with a solution to fix and which part needs to be fixed

[@notfallmed]

TNX Peter, schönes Wochenende 73

[@TRXLab]

Dir auch ein schönes Wochenende, Peter! 73

[@ntacell11]

HI Peter, do you have any video for Kenwood TS-450S for Audio is very low even knob is all the way to right but yeah this is good experience for Yaesu FT-747GX. Thanks in advance

[@TRXLab]

mo Thomas no video on the TS-450 online...

[@mikesawyer1336]

Hi again Peter. Thanks for a fun look at the inside of the FT-747 GX. As a kid I loved this rig. Always wanted one - but never actually purchased. Happy to see they are still in service. The old PCBs and huge components made me laugh. Do you work on any tube gear. I never learned any tube theory?

[@TRXLab]

Hi Mike, yeah the 747 is still a nice radio and as long it is working it works fine...All made in THT very old school haha..Yes I also work on tube equipment and it is not so hard to understand but you need to be much more careful as you are working with high voltages but other than that it is pure fun ..Thanks for stepping by 73

[@srs26]

Hi Peter, very useful and informative! Thanks!

Ok i saw it. My last question; is it possible to share connection diagram for rotary encoder? I have ec11 mechanical rotary encoders but i couldn’t manage to connect it. Thank you very much, 73 de TA3LKU.

[@TRXLab]

If it is the same encoder as I used in my video you only need to wire 4 wires up...

Did you make rotary encoder replacing?

[@TRXLab]

Yes shown in video #7 and #8. Hope that helps. 73

[@waynephelps7428]

Hello Sir. I have an intermitant erratic signal problem on my FT-747GX only on upper sideband. Would my problem be on that same circuit board? Thanks and 73

[@TRXLab]

No it can be anywhere...

[@larrypridgen4785]

Hi Peter Where can I find the Radio Today article on filter switching?

[@TRXLab]

you might find it on the web

[@peterhansen8216]

Nice vid peter, But I'm pretty sure you knew the connection on the board was bad before you even removed the board. But thanks for helping us see it by poking at it for 5 minutes.

[@borayurt66]

It was actually more like 10 minutes of poking. :-) Nevertheless, I enjoy each and every video of Peter including this one. He is very methodical, professional, and fun to watch...

[@TRXLab]

Hi Peter, well let me say it this way I had a very good guess...Thanks for watching 73

[@vu3mkhvu3mkh97]

Hi ! I'am having this rig and need to open the front panel for repairs. The MODE / VFO MR and such buttons are not working properly. Can you please share with me how to open the front panel of this YAESU FT 747 GX. Thanks.

[@mikecappelli]

Hi there Alton I have a yaesu FT80C which was handed down to me by my late grandfather. It is not transmitting on any band, the on air light comes on it draws about 2 or 3 amps but the S Meter does not move at all. The RX works great the S meter moves on RX but no TX at all. If I tune another radio next to it to the same frequency I can hear myself on it but it has no amplification. I have been through the PA I have checked all the voltages at the initial drive, pre drivers and final transistors as per the service manual and they all check out ok. I am getting voltage to the pa as the relay clicks when I press the TX button. As this rig has real sentimental value to me I really want to get it going but no one here in Australia wants to touch it, they won’t even book it in for a look can you help me please??? and point me in the right direction

[@kevinkang4308]

I can see ya hand in the solder, haha

[@Bass.Player]

I suspect that the loose so239 connector caused the pin to break the solder joint on the pc board

[@TRXLab]

Yeah that is absolutely possible...Thanks for watching 73

[@charlieoscar09]

Peter can you speak about the Soldering Filter you use in another video thanks

[@TRXLab]

oh you are talking about the Hakko smoke absorber. Well it is not the best and I'm going to upgrade it to a more professional filter system but it is the minimum you should use if you doing solder work on a regular basis.. 73

[@iw0hex]

Thanks for video, dear my friend. 73s Pasquale IW0HEX

[@TRXLab]

Always glad to see you Pasquale! Take care my friend 73

[@TKomoski]

Hi Peter, do you often check for modifications on radio's the old man sends you? Do you have a listing of modifications for different manufactures products. I remember when I was repairing TV's you would get a service bulletin every once in awhile about a mod that needs to be done. Is that like with radio's as well or do you search for mods yourself. Great repair as always and watching your video saturday mornings with my coffee. Cheers 73

[@TRXLab]

Hi Tom, well it is not like in the old TV business but there are here and there some bulletins describing a modification...But basically we search for mods.. Thanks for watching 73

[@1112223333111]

hard on the finals. he was lucky

[@TRXLab]

yes that can be a final killer...Thanks for watching 73

[@jeromegrzelak8236]

I understand they had a heathkit version of this radio kg6mn

[@TRXLab]

Ah never heard and never seen. Thanks for comment! 73

[@harbselectronicslab3551]

That SO239 was very loose on the PL259 centre pin.......

[@TRXLab]

Well almost 30 years of use can't be hide lol. Thanks for watching 73

[@vk2wgw]

That factory solder job on the back of the SO-239 is very poor.

[@TRXLab]

Hi Glenn, well it looks more pure on the video as it was in reality...Thanks for watching 73

No not the same. I have this module: goo.gl/KtvXjT

[@srs26]

Hi Peter, very useful and informative! Thanks!

[@TRXLab]

Thanks for watching 73