Kenwood TS-570D Ham Radio Repair & Troubleshooting a Transmitter Fault
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- Опубликовано: 6 сен 2024
- In this video I troubleshoot and repair an intermittent transmitter problem which was causing a lot of cross band interference I also try to cover the basics of how the transmitter works in the radio. It’s quite a long video as it was not easy to locate the problem. This is a component level electronic fault finding and repair video. Please feel free to leave comment as we’d love to hear from you.
Note: Apologies some of the circuit descriptions are a little out of sync in the schematic diagram section of the video regarding Q1 and the ATU as I need to find a better way of doing this. Наука
Thank you for the repair video. This will be helpful for others who need to repair their rigs and using fault finding techniques.
Hello John. Very interesting video, and extremely helpful in other ways. I recently received the Japanese version of the TS-570S that is set to 50 watts of total output power. I kind ham in Japan sent me detailed information on how to perform changes to make it a USA standard TS-570S. One jumper added at R30 and one 1K SMT resistor removed on the board. The board in this note is the board holding the memory battery. Now my challenge is the proper set up using the programming plug at the rear, and entering the service mode to set ALC and idling current for the rig. The service manual is not clear or the terminology is a bit vague. I'm happy I found your channel, for sure!
David Fleming NS8S
Very interesting video with lots of detail a methodical approach and not too much waffle . It's given me a good insight into my own TS570 which the antenna tuner won't match even the slightest miss match . Full RF output on every band though and swe meter on the radio giving accurate readings so not quite the same issue as you had. Keep your videos coming as I for one think they are some of the best diagnostic videos on you tube !
I like your use of the Afrikaans word "lekker".
Great work again John, would you be interested in playing with a Marconi 2955A for the channel?
I have one that fails it self test ?
Hi yes I would be very interested. There is a lack on the OM modules for these test sets and I am planning to make some Hybrid boards that has the correct gain and impedance as a drop in replacement. I could really do with a test subject. The 2955 in the video is not mine as it’s in for repair. Please send me an email and we can discuss this further m0xfx.channel@gmail.com Best Regards John
Excellent video. Thank you for taking the time to explain the signal flow through the different parts of the circuit. Take care, 73, Keith kg2ix
You are welcome!
U are just a genius my man. What can i say its nice to watch an artist at work. I like these radios as well. They actually work better than the ts590 on ssb.
Hi Gary, It was a real pain of a fault if I’m honest but it’s a great feeling when you crack it. I’m glad you enjoyed the video. I’m on the scout for more radios so I can make more repair videos. Best Regards John
Excellent diagnostics John. Well done on the repair.
Thanks mate
Very interesting John and it was very helpful to go through how everything fits together. I will apply lessons learned to my own pa fault and see if I can figure out why I have no output on my Kenwood 👍
Chris you could always send your Kenwood up to me and I will fix it for you and make a video. Where about are you based?
@@M0XFXUK I’m based in Doncaster John. The radio is really a basket case with a lot of the internal tins missing and a very severely cracked cpu board that I’ve bodged back together. Even the power button was fused together until I stripped and repaired it 😂. I brought it to learn with and it’s certainly made me think at times. I’m not sure it’s something you would want to work on to honest 😂😂😂
Hi John,
I'm currently working on my TS450SAT which is new to me, only producing around 20 watts all bands, all modes.
I don’t have a great deal of my test equipment here for rf, so limited and struggling somewhat.
I need to disconnect whete the rf comes into the amplifier as you've done here, without an analyser I was wondering if I could scope the signal ....
The control for the alc can be set, a gew moments later on trying it again it needs adjusting - I'm about to test the controls for the pwr, carrier in case they've taken a hit, before delving into the amplifier circuit.
It's a good 20 years since I've been inside a radio almost! I still do electronics kit, just not rf for a good while now.
The output transistors I believe test okay.... although clearly not amplifying the signal, so potentially not being driven.
The IF board did have the usual c104 leakage. Some clown had changed the caps, but hadn't cleaned the electrolyte from the board. Given my lack of confidence I've replaced them all again and tested out the traces, despite looking grim they're alright thankfully.
I'll have a look through the diagrams shortly for the amplifier once the dials are tested and it's back together.
I can't stand being beaten 😂
Any advice welcome 🙂
M0TAH
Hi there, so if the radio is producing low RF output, I would check the current draw of the radio in TX and make sure it is not excessive compared to how much RF the radio is producing. Also if you want to test the PA you can feed it directly with a signal generator but make sure the radio is set for the frequency you are injecting so the correct LPF is switched in. Around 0dBm normally produces full power, better to start low and creep up the signal. I hope this is of help.
@@M0XFXUK great thanks John I'll have a look... I've a very old kit signal generator I'll hunt out.
As for power, on tx it's using around 7amps or there abouts which would be roughly in the right region for the 25w output
I did enjoy this and very helpful if I have a problem with my 570DG.
I have subscribed and going to binge watch your channel
I am really happy that you like the channel, to be honest I used to work in the radio game back in the 80s and 90s, but these days I enjoy repairing gear as a hobby and making videos in the hope that it help others. Thank you for the comment.
Very interesting troubleshooting, thanks 👍
I've had a few radios in over the years with damaged LPFs , Mainly the filter that covers 10 MTRS , This in my case was due to the radios being turned upto the maximum for CB , Running 120-150 watts or more on FM for any decent lenght of time isn't good for the LPFs as you know , I had to send to the USA for a replacement LPF PCB for the last radio I did , It was a FT-757 GX 2 .
Hi Marc, Yep the 10 meter band is generally where all the action is. I think you hit the nail on the head as people wind the TX power up and operate them on 11 meters with a prolonged carrier. You can repair the LPF’s as a lot of the time it’s just the relays have melted inside but you have to be careful if you have to replace any of the caps as you have to get the right ones. I know the FT-757 GX 2 as I have repaired many of them over the years and they are still a good rig if they are running right great to hear from you, best regards.
Great video,
Glad you enjoyed it
Really useful to follow that John .
Hi Houdi, great to hear from you as always. I am glad you found the video helpful, I always try to go over how sections of the radio work in the hope that it helps people. Best regards
Well done. TU TU x 100 as the kids say.
Nice clear explanation buddy 👍
I am glad that you found the video interesting, thank you for the comment.
Nice work John, keep it up!
Thanks John
this is already the second time that I have replaced a driver, it seems that the swr protection no longer works and from menu n 46 I no longer adjust anything. What may have happened?
Hi, sorry for the late reply,. What transistors did you use to fix the driver stage?
i assume that atu is a "t" match,are they better than an auto atu with steppers and air variables like the ts-850 atu?
Hi Paul interesting comment and question. I guess it could be described as a T match. Regarding ATU's using stepper motors with rotary air caps vs relay type switching in capacitors and inductors, to be honest I I cant really say which is the best as both systems work well. That being said I do find the switching type ATU to be more reliable and faster to reach tune but that being said I guess this would vary with different designs and manufactures. I would think that a stepper motor type would be better at tuning higher RF power perhaps.
Any one know some 1
That would have a good look at my 1
That was left by a good friend
Yabba Dabba Doo..
STOP the Ads, as most ads have Malware and are killing computers!!! Sorry but I don't watch crap with ADS!!!
Hi mate, I am sorry to hear that you are having issues with the ads from our channel. We have the channel monetised to try and recoup some of the outlay of making the content. If we switch it off RUclips still runs ads anyway. I will take a look into how I can correct this. Thank you for your message.