Good to see that this poor mistreated unit comes back to life! Looking to the new knob.
@TheRadioShop
2 жыл бұрын
Thanks Stefan. Fun working on these even with all the problems. Just scanned through your channel and liked what I saw, Subscribed!
@dl7majstefan753
2 жыл бұрын
@@TheRadioShop Thanks! Your subbing is like an accolade for me ...
@lylewatts6370
2 жыл бұрын
Yes it's easy to miss somethings but taking your time to check every stage of the circuit does pay off. Thanks for the great video and will be waiting for part 3.
@TheRadioShop
2 жыл бұрын
Thanks Lyle. Part three soon.
@JxH
2 жыл бұрын
I have one. They're about 40 years old. I bought mine many years ago from someone that had it on a boat, about $100. Cleaned it up cosmetically (cleaning and paint) and it already worked fine. Put it away, take it out a decade later and it still works perfectly. Only flaw is the missing rubber from the tuning knob, probably rotted off like they all do. Great radio, although it lacks many features of more modern ones.
@andrewbarnett84
2 жыл бұрын
I've been repairing two TS430S transceivers with problems normal to the age. One I bought from a local radio club in bad external condition, with no output and display not working. The second was brought to me by a new ham, who paid around $400 for it externally it looks 100%, but displayed 63.00 only and did nothing. It came with two faulty microphones as well. Funny thing the ugly one I bought for $75 just had a few solder issues on the IF board (sockets pulled out of the PCB), and a damaged mic cable. It still has the dirty relays on the filter board to sort but it now works. The new hams rig however, has been a nightmare, bad solder on every board, every single socket connection dry, and someone had modified it for either RTTY or FT8 or something. I had to undo all that to get it to the point I could use the factory diagrams. I found a burnt track on the back of the Mic socket (Earth connection), as that was strange, I looked at the power cable supplied and it had a four way disconnect in the middle of the cable and both earth parts were loose. So I suspect the Earth wire on the Data connection plugged into the Mic burned out due to no other Earth to the PSU, and drawing excess current. Someone had also tried to modify the radio to wideband, but it is a W model and none of the band restrictive components are present. They succeeded only in damaging the components around the area. In all there were over 50 faults and hundreds of solder issues. I've replaced many capacitors, and adjusted the PA balance. The new Ham has bought two new (old) Mics so I'll test them tomorrow, and try out the rig under RF TX. The Receiver is working well and I cleaned he relays on the filter board, which made a huge difference. I wish you have a great Christmas and enjoy the company of Friends and Family at this Festive time of year. 73 Andrew ZL2ALW
@TheRadioShop
2 жыл бұрын
Thanks for sharing that, I love to hear others repair stories. Sounds like you had your hands full, Merry Christmas.
@ramonreyes7854
Жыл бұрын
(Success!) I decided to take a look at the print side of RF board and noticed some of the soldering seem to need reflowing. Instead of blindly reflowing suspect joints, I started poking around wiht my scope on the RF board which I managed to leave hanging in the air with all connectors plugged in and print side on top. It was good that there was enough slack in the cables. I powered up the radio and began tracing the TX signal path starting from J1011 (tx if in). When I got to a terminal of the double balanced mixer consisting of Q5 and two toroids T19 and T20, and touched it with the scope probe, rx noise suddently went up on the external speaker. So I pressed the Mic ptt and what do you know, there was power output! I then reflowed the joints in that area and now I am testing it now. I think the components of this radio are good quality. It is only the solder at some points that may require reflowing. It is to be expected for a radio several decades old. 73 DU1FV
@na5y
2 жыл бұрын
Really enjoyed this one Buddy. That PA unit sure looked in a sorry state. Looking forward to the diagnosis in the next video!
@TheRadioShop
2 жыл бұрын
Thank you very much.
@richardmills5450
Жыл бұрын
Bee nice to have a bit more detail on the repair and the test setup. Cheers
@ukrainehamradio
2 жыл бұрын
Good job! Thank you for save another one old horse.
@TheRadioShop
2 жыл бұрын
Our pleasure!
@michealmihailovic4128
2 жыл бұрын
Part 2 excellent Buddy as usual easy to follow looking foward to part 3
@TheRadioShop
2 жыл бұрын
Thanks
@alandrury9955
2 жыл бұрын
Thanks Buddy! Another masterclass in sensible, considered fault diagnosis. I'm looking forward to part 3. Have a merry Christmas and stay safe and healthy
@TheRadioShop
2 жыл бұрын
Thanks Alan for the kind words. part 3 coming soon,
@danabland9928
2 жыл бұрын
THANKS BUDDY!
@billnicholson2470
2 жыл бұрын
Great video Buddy! Can't wait for part 3. I have a Kenwood TS180S that works fine but the plastic couplers should be replaced. Problem is I can't find any and don't have any equipment to make them. Happy Holidays.
@TheRadioShop
2 жыл бұрын
Bill, Thanks and stay in touch with me. I may be able to help with that.
@jackmartinkd9pdy891
2 жыл бұрын
Great video Buddy. Enjoy your trouble shooting. Have a great 2022!
@boxingday11
2 жыл бұрын
Thanks Buddy, keep safe and have a peaceful Christmas 👍🇬🇧
@TheRadioShop
2 жыл бұрын
Thanks, you too!
@rusty1187
2 жыл бұрын
Merry Christmas, Buddy! Thanks for all the tips and hints that you have shared with us over the years.
@TheRadioShop
2 жыл бұрын
Merry Christmas and thanks for watching
@extreme978
2 жыл бұрын
Dang your a good technician! great video buddy, very entertaining.
@TheRadioShop
2 жыл бұрын
Thanks, I am an ok tech but nothing that special.
@DK-vx1zc
2 жыл бұрын
Great job. Very interesting! I learned a lot. Thanks for sharing.. Glad you are saving this radio.
@TheRadioShop
2 жыл бұрын
And thank you for stopping in.
@leobyn
8 ай бұрын
hace poco adquirí un ft 77 y lo estoy restaurando con ayuda de tu aporte visual, espero la 3 part saludos desde Ayacucho Perú
@johnrazor8720
2 жыл бұрын
Thank you for repairing these old radios. You keep repairing them and we’ll keep watching. Merry Christmas and happy New Years.
@TheRadioShop
2 жыл бұрын
Thanks John and Merry Christmas to you.
@HoardDredger
2 жыл бұрын
Hi, Also have the band selector problem that it is cracked.. If you could do a detailed repair video on the fix of this , Would be very grateful,, Love the channel ,,
@kevinmccool3719
2 жыл бұрын
You need to set that bias control for a certain amount of idling current typically instead of setting it by just reading the voltage at the base of the 2sc2290 transistors. That's how it was done in the Kenwood 120s and 130s. You set the idling current for the drivers with one pot then set the output transistors with another pot. I know on the yaesu ft890 it was the same method.
@ukrainehamradio
2 жыл бұрын
There is a one pot only in this PA
@TheRadioShop
2 жыл бұрын
That is correct. Not sure if you are just telling us that or if you think I had set the bias. If the latter then you skipped too much of the video. The bias (idle current) was never set in this video. We only checked for current and voltage. As said in the video the bias current cannot be set until the RF drive is corrected. Now if you take a look at the schematic you will see there is only one VR to adjust the bias current on the FT-77. It is a bit different that some of the others.
@michealmihailovic4128
2 жыл бұрын
excellent video Buddy always learn something new i am impressed what u gear u have very impressive many hams only dream of keep up the good video's Buddy they are a must see.
@TheRadioShop
2 жыл бұрын
Thanks for the nice comment Michael
@johnblake8424
2 жыл бұрын
I am already waiting got part 3, this is a master class. I hope you explain how you set the bias on the power amp before the project is completed. As I mentioned, I have one of these, I have had it since the late 80's, still don't know if it works...
@TheRadioShop
2 жыл бұрын
Thanks John. Yes I will explain and show how the bias is set, it is actually called idle current in this rig. Let me know how yours turns out and thanks for watching.
@peterharband326
2 жыл бұрын
Thanks Buddy. A happy and safe holiday to u and ur family
@TheRadioShop
2 жыл бұрын
Thanks Peter ahd Happy Holidays
@old64goat
2 жыл бұрын
Merry Christmas and a Happy New Year Buddy.
@TheRadioShop
2 жыл бұрын
Merry Christmas Bill.
@bblod4896
2 жыл бұрын
Merry Christmas and Happy New Year to you and your family.
@TheRadioShop
2 жыл бұрын
Merry Christmas to you and yours Mr B.
@cuban9splat
2 жыл бұрын
Excellent. Looking forward to part 3. Would also like to see how you design and turn a new knob. Thanks for letting us all watch over your shoulder, Buddy. 73 and Happy Holidays de K7RMJ Frank
@TheRadioShop
2 жыл бұрын
Thanks for being there Frank. Always a pleasure. Merry Christmas my friend.
@pavil58yt
2 жыл бұрын
It's interesting in that I had an FT757gxii that was DOA. The same cap in the finals module was burnt to a crisp. There was another nearby that was burnt too. My finals were good though.
@buildstoys
2 жыл бұрын
Great to see the continuation on the Yaesu Buddy!
@TheRadioShop
2 жыл бұрын
No problem, should be two more videos in the series if all works out ok.
@jrumiano
2 жыл бұрын
Nice job repairing the power amp section. I'm looking forward to the next video.
@TheRadioShop
2 жыл бұрын
Thanks John
@vicmabus1532
2 жыл бұрын
Those transistors blew their tops!
@TheRadioShop
2 жыл бұрын
Literaly!
@PapasDino
2 жыл бұрын
Great work as usual Buddy...look forward to finding out the real issue with the rig. Merry Christmas and Happy New Year! 73 - Dino KLØS
@TheRadioShop
2 жыл бұрын
Thanks Dino. The main issue has already been found, Video in progress. Merry Christmas to you.
@jdmccorful
2 жыл бұрын
Moving along, great sleuthing. Thanks for the look.
@TheRadioShop
2 жыл бұрын
Thanks
@mikefinn2101
2 жыл бұрын
your still doing a fantastic job. I think your one of the best. Love the no nonsense approach. Honest repair man. Love your videos. Learned so much. 73s wb7qxu
@TheRadioShop
2 жыл бұрын
I appreciate that! Thanks
@alpcns
2 жыл бұрын
That poor thing was butchered - but Buddy to the rescue ;-) It's a true pleasure to watch you root around and diagnose the (many) faults and hacks in that radio. Looking forward to the next episode! Merry Christmas and Happy New Year!
@TheRadioShop
2 жыл бұрын
It had a hard time for sure, Thanks for watching
@bmh67wa
2 жыл бұрын
Merry Christmas Buddy!
@TheRadioShop
2 жыл бұрын
Merry Christmas.
@Joe-KN4IFI
2 жыл бұрын
Thank you Buddy for all that you do. I always look forward to your videos. Merry Christmas and a happy New Year to you and your Family.🎄 73 Joe
@TheRadioShop
2 жыл бұрын
Appreciated Joseph, Merry Christams
@timothyrehfeldt5709
2 жыл бұрын
You always do a fantastic job and I learn a lot from you. Thank you for allowing us to watch you work. I can't wait to watch your next episode on repairing the FT-77. There's one screw under the input transformer I cannot get to. I think I need to pull the transformer out. Not sure. Have you been able to remove the board from the heatsink?
@jwrtiger
2 жыл бұрын
Hi Buddy, thanks for all the great videos. I think that just a minor mistake was made in several places in the video. You mentioned the signal voltages in the microvolts but the scope showed millivolt levels for those signals. May be I am missing something. I am very impressed with your troubleshooting techniques and attention to details. Have a great holiday!
@TheRadioShop
2 жыл бұрын
You are correct, Should had been saying millivolt. Happens when you get old...
@hectorpascal
2 жыл бұрын
Nice trouble-shooting demonstration, Buddy. But surely those "bullet" automobile connectors on the 13.8V PA supply lines are not standard Yaesu parts? That would immediately ring bells in my head about the quality of the "technician" who previously worked on the rig!
@TheRadioShop
2 жыл бұрын
I have never seen a brand new FT-77 but it is original as I am told. I have seen this in other rigs as well. I guess this is the best they could come up with for high current.
@hectorpascal
2 жыл бұрын
@@TheRadioShop It would certainly work OK - just seems so "un-Yaesu-like"!
@donaldshields2483
2 жыл бұрын
Another very good job and just amazed with all your knowledge I am a ham my card is kilowatt number one Eco Mike whiskey but I wish I have a butt head about a 10th of your knowledge I really enjoy watching you and keep up the good work and I will keep watching god bless
@ramonreyes7854
Жыл бұрын
I acquired an FT-77S recently. It looks like the RF board, just like yours, is not giving enough tx drive. Accdg to spec sheets, the PA driver C2166 needs about 250mw drive to give an output of 6W. At 50 ohms, 250mW is typicaly 3 volts according to some table (Pasternack) I saw. The voltage going from the RF board to the PA board is nowhere near that. The radio has good enough receive for now. It seems someboy has turned a few pots on the IF board and re adjusting some of them has made the receiver start working. This means the band pass filters in the RF board should be OK, since they are used in both transmit and receiver. (is this a right assumption?) It is only the transmit devices (Q01 2SK125 and Q04 3SK73, in there I should look further into. BTW I have the 10 W model and putting it on a wattmeter and keying on CW just barely moves the needle at 5W full scale setting. 73 DU1FV
@mikesmithg0rfd356
2 жыл бұрын
thank you
@TheRadioShop
2 жыл бұрын
You're welcome
@claudiobio
2 жыл бұрын
Thanks Buddy. Every video is a master class. Am trying to fix my FT-77 PA was the first problem, I replaced both final transistors, and other PA components and now I have 100 watts on 80 meters band but when going to 40, 20 up to 10 meters power decreasing. I was playing around RF board and supposedly according service manual it is aligned. I will appreciate any suggestion. Happy Christmas and Happy New Year from Perú.
@TheRadioShop
2 жыл бұрын
Are you able to disconnect the PA and check wattage in millivolts direct from thje RF board? Could also be a problem in the LPF unit.
@mrjg1013
2 жыл бұрын
Hi Buddy, long time subscriber! May ask, when using your oscilloscope if it’s possible to show how your making the connections to the pieces being looked at! I have a new oscilloscope that I want to learn to use… so I wanted to learn to make connections without destroying the scope! Just a request by no means trying to tell you how to make vids! Your vid’s are already great!
@TheRadioShop
2 жыл бұрын
No Problem, I can do that. With solid state units you do not have to worry as much as you do with high voltage rigs. Most connections on rigs like these are direct to the circuit with the standard scope probe.
@boldford
2 жыл бұрын
I bet the magic smoke came out of those transistors.
@TheRadioShop
2 жыл бұрын
Thats the truth
@justmejonboy
2 жыл бұрын
I love these videos, I look forward to the next in the series of the FT77. I have also been working on my own FT77 that has been hidden away for 20 years. It is the 10W version and seems to generally be working ok now. One thing that puzzles me is when on the 18 mhz band when I key CW I do not get any ALC or FWD ref on the meter. Every other band looks good. I have checked the path through the LPF when switching the rotary band selector in case it was a contact issue but all seems good. Would you have any suggestions as to where I should be looking. I suspect it might also be a bit deaf on receive on the 18 mhz band. Many thanks, I love your work,
@TheRadioShop
2 жыл бұрын
I think I would revisit the LPF board. If you are doing a continuity test it may not reveal the problem. An arced over contact and show resistance by a signal may not pass.
@justmejonboy
2 жыл бұрын
@@TheRadioShop I will have another look and report back. Thank you for your reply.
@DonDegidio
2 жыл бұрын
Hi Buddy, Have enjoyed this repair series and looking forward to part 3. You mentioned making a metal replacement coupler on the lathe. That coupler is nylon. Could it be that they wanted nylon to isolate that metal shaft? You and the family stay safe. 73 WJ3U
@TheRadioShop
2 жыл бұрын
Don, Yes it has to be insulated, that prevents RF from traveling down the shaft. The coupler would be made from two pieces of aluminum with a nylon center that joins the two pieces together, Not only does it act as an insulator but it also is like a univeral joint. Thanks for watching.
@DonDegidio
2 жыл бұрын
@@TheRadioShop Hi Buddy, What is the diameter of the shaft. I think I have some 1/4" Oldham couplers around here. WJ3U
@TheRadioShop
2 жыл бұрын
@@DonDegidio They are 1/4". Really need to find a soruce but have not. . Thanks
@DonDegidio
2 жыл бұрын
@@TheRadioShop Hi Buddy, Found some couplers that use a rubber spider, but look like 1/8" bore. You could open it to 1/4" on the lathe. OD 5/8" OAL 7/8". Would this help? Can Priority Mail them tomorrow.
@TheRadioShop
2 жыл бұрын
@@DonDegidio Most likely can be. Thanks
@bblod4896
2 жыл бұрын
Wait a minute, is that the radio I sent to you? 😂
@TheRadioShop
2 жыл бұрын
Yep, same one. I had loaned it out and this is how it came back.
@bblod4896
2 жыл бұрын
@@TheRadioShop Amazing. I forget all about it. 😆
@johnblake4503
2 жыл бұрын
Did you ever make any progress with the RF board ? Any other videos in the series ?
@TheRadioShop
2 жыл бұрын
Will get back to it shortly John. Not much time in the shop at the moment
@johnblake4503
2 жыл бұрын
@@TheRadioShop I have been working on a Yaesu FT77S for sometime now, this is the 10W version. The radio now works well, I have totally recapped the radio, I think it was about 50 or 60 capacitors. The one area I am not exactly sure about is if I Key on CW the unit does produce exactly 10 watts. However on speech using a peak hold SWR meter it is not possible to get above about 5 watts which seems a bit low. I presume I can rule out an issue on the RF board as the the CW signal path also passes through the RF board. Presumably I should be looking on either the AF or IF board as the CW does not seem to pass these boards ? Any help appreciated. Love your channel.
@johnblake4503
2 жыл бұрын
A general question, for a 100w PA like on the FT77, thinking of ohms law, what would be the likely relationship between voltage and current. I notice the capacitors in the LPF are rated at 50v so I’m presuming less that this ? For example ? 30v * 3.3amp would equal 100 watts ?? Or am I missing something ? I was trying to see the amplitude on the scope when you keyed the transmitter with the signal generator attached but couldn’t ? Many thanks.
@braveheart5280
2 жыл бұрын
Hello Radio Shop- Just got a B&K 747 tube tester. Is there anywhere i can get a power transformer ? THANKS
@TheRadioShop
2 жыл бұрын
Are you sure the transformer is bad? These are hard to come by as it has 30 secondary leads. And they were built only for tube testers.
@braveheart5280
2 жыл бұрын
yup, smokes up the shop. Tester has bad caps and rectifiers. hope someone on Ebay sells one real cheap with a broken meter or switch panel. Thanks for your help and happy holiday's.
@monolitesounds
10 ай бұрын
great. got one that dont recive. any tips?
@kermitbob635
Жыл бұрын
Hi could you drop part 3
@cajuncoinhunter
2 жыл бұрын
Dat was a lot of buggered up solder joints in Der .... Even when I was a preteen I was soldering way better Dat.... Too many parts not connected and fried , WOW I'm surprised that it made 5 to 6 watt's of power that I seen in the Part one ....
@jeffalessi
2 жыл бұрын
Shoddy or Butchery....
@johnblake4503
2 жыл бұрын
Have you any idea what an equivalent replacement for a 2SC2509 (used in the 10 watt version FT77S) PA ? Many thanks
@TheRadioShop
2 жыл бұрын
Look for a NTE236
@johnblake4503
2 жыл бұрын
@@TheRadioShop Thank you very much, I will have a look for your suggestion, I have lost count how many capacitors I have changed by now, the hardest board to get to looks like the regulator card and I think I have a problem on there. The switched TX 13.5v supply seems to be just over 12, I see there is a large C on the back of this card. I was hoping to find a way without unsoldering all the tiny supply wires as there is no plug / socket on this card. I think a soldering iron is the only way, doesn't seem easy to access from the back, still loving your channel ?
@johnblake4503
2 жыл бұрын
@@TheRadioShop Not had much luck trying to find these either.
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