Hi Buddy. Love your videos and your process to troubleshoot and repair. Please let me know what the serial number is of this TS-940. I have a very late serial number. I believe Kenwood had many issues like this and the dots issue with the early serial number radios. Thanks.
Hi Buddy! I've. a close friend that has had real issues with Kenwood TS series. Is cracking of the solder on the boards common to the Kenwoods of that era, or is it just common with all manufacturers as the units age? Really enjoy your videos. I have learned so much, thanks to you. 73 de AA7MO
I have also Icoms (IC-781, 761) and Yaesu FT-1000D from -80's and TS-940S which is worst of them with soldering. Yaesu I just checked and it was beautiful to see that there were no actual repair work to do with soldering. My TS-940S RF-unit was worse than on this video. I have gone thru nearly the whole radio and it fixed a lot of issues. All the radios from 80's have something to repair now, but you have to be patient and check the usual things first. A lot of info is available and that is a great thing. :)
Yes, very common to that era when these were made. These boards were wave soldered. I just think there were way to many errors in the process back then,
Agreed! and that reminds me I need to order more D5. I really hate the new cans they have now. Waste more than you use. I now just fill up little squeeze bottles that have needle tips on them, make it last so much longer.
They sure have a lot of tacked on components after building the PC board. Looks like they found some problems in the design and didn't want to do a roll on the PC board. I wonder why so many cracked solder joints? Not heat related as the components are low power. I used to work in a failure analysis lab. I would have loved to take a look at it with some of our equipment.
The TS940S is famous because the PLL oscillators was filled with a wax to reduce microphonics..unfortunately, it melts with heat, and then cools and reforms. Over time gets into the solder cracks on the board, causing an flakey connections. Pull the PLL osc and check every solder joint. You most likely will see that the wax will make it through the board.... so clean up the bottom.
Again, thanks for sharing. Although you showed that the new RF PA board works in delivering 100 watts in FM mode, I’d be interested in its performance in a SSB mode. Specifically, I want to know how much out of band emissions it causes when tested with a two-tone test (for example, 900 Hz and 1300 Hz sine wave audio input, with output at 100 watts). Any non-linearity of the amplifier would show up in this test. Excessive emission would bleed into nearby frequencies and potentially cause interference.
From my experience, if you don’t want to see such a device on your desk again and again, you need to be prepared to immediately re-flow almost all the solder joints, replace all the electrolytic capacitors, disassemble and clean all the switches and potentiometers.
I think this is the best diagnosis and repair channels. No crap involved, we see it as it happens! Thankyou!
I really appreciate those kind words. thanks
Yep, I can see the halos around the pins and component leads. Well, a nice cup of tea and some background music, and a soldering you will do. 😊
Yep, lot of soldering and pin cleaning on this one.
I worked on a friends. It was one of only a few failures for me. Also consider pulling socketed chips & cleaning those. Good luck.
All connections in these must be cleaned. And as you said the chips are a must/
Cool. I forgot about those electronics microscopes. I'm a order one.
They do good for what they are. I use both of mine constantly.
@@TheRadioShop i can't see small fer shit anymore. Lol
I have one and I regretted buying it. The image quality is disgusting and my smartphone's camera copes with this task much better.
Hi Buddy. Love your videos and your process to troubleshoot and repair. Please let me know what the serial number is of this TS-940. I have a very late serial number. I believe Kenwood had many issues like this and the dots issue with the early serial number radios. Thanks.
Hi Buddy! I've. a close friend that has had real issues with Kenwood TS series. Is cracking of the solder on the boards common to the Kenwoods of that era, or is it just common with all manufacturers as the units age? Really enjoy your videos. I have learned so much, thanks to you. 73 de AA7MO
I have also Icoms (IC-781, 761) and Yaesu FT-1000D from -80's and TS-940S which is worst of them with soldering. Yaesu I just checked and it was beautiful to see that there were no actual repair work to do with soldering. My TS-940S RF-unit was worse than on this video. I have gone thru nearly the whole radio and it fixed a lot of issues. All the radios from 80's have something to repair now, but you have to be patient and check the usual things first. A lot of info is available and that is a great thing. :)
Yes, very common to that era when these were made. These boards were wave soldered. I just think there were way to many errors in the process back then,
I have a old ts 850 they have there issues also , knock on wood mine is still working well :)
I agree, but seems like when the 9xx sies came out so did more problems.
Hit all those plug pins with DeoxIt D5. You may have to re-solder that whole board, and remove all of that old flux!
Agreed! and that reminds me I need to order more D5. I really hate the new cans they have now. Waste more than you use. I now just fill up little squeeze bottles that have needle tips on them, make it last so much longer.
@@TheRadioShop - I like them either way.
They sure have a lot of tacked on components after building the PC board. Looks like they found some problems in the design and didn't want to do a roll on the PC board.
I wonder why so many cracked solder joints? Not heat related as the components are low power. I used to work in a failure analysis lab. I would have loved to take a look at it with some of our equipment.
Yes lots of bodged upgrades over the years. During the time of these radios I think there were errors in the wave soldering procedure.
Good luck 👍 nice radio
Thanks
The TS940S is famous because the PLL oscillators was filled with a wax to reduce microphonics..unfortunately, it melts with heat, and then cools and reforms. Over time gets into the solder cracks on the board, causing an flakey connections. Pull the PLL osc and check every solder joint. You most likely will see that the wax will make it through the board.... so clean up the bottom.
Again, thanks for sharing. Although you showed that the new RF PA board works in delivering 100 watts in FM mode, I’d be interested in its performance in a SSB mode. Specifically, I want to know how much out of band emissions it causes when tested with a two-tone test (for example, 900 Hz and 1300 Hz sine wave audio input, with output at 100 watts). Any non-linearity of the amplifier would show up in this test. Excessive emission would bleed into nearby frequencies and potentially cause interference.
Hey Buddy!
Howdy
From my experience, if you don’t want to see such a device on your desk again and again, you need to be prepared to immediately re-flow almost all the solder joints, replace all the electrolytic capacitors, disassemble and clean all the switches and potentiometers.
Hi, what’s that goop you put on the joints that you were reflowing at 8:35? Never seen that…
That is flux. It helps with the flow of solder.
@@TheRadioShop thx, I’ve never seen white flux.
Most frustrating radios I’ve ever worked on!