Hi Peter I found part2 as you say setting the bios of the transistors are very tricky well done another success and another happy customer :) though it was funny about that power pot it shorted out the radio it is a joy to watch you fault finding and you need to have the right equipment before you tackle anything thanks once again :)
I am so happy TRX! I fixed my Stryker 955 after 2 months of down time. There is no one close by to work on it. The closest guy is D-Rail 2 hours away and don't take mail in and is not open Weekends. The 1st Audio amp TDA2003V that I put in died quickly because of a burned SMD FET on the Ground side of the speaker circuit that I found later. Also found a missing SMD resistor that provided chassis ground to the speaker. All this because I repaired my speaker plug. One strand of positive copper wire got soldered to the negative and I failed to see it. Poor cutters left one strand that didn't get cut.😃
@@TRXLab The Stryker 955 schematicas are clear as bell its just that so many things connect to one global path that runs throughout the radio. Its hard to trace things from end to end. And of course very few voltages are listed and no block diagram. Of course you could probably make worlds more sense out of it than I can. 🤣😃
Hello again, This time, thanks to your video've learned a lot and now I could fix swje CB-radio, which was damaged in AM...... You did a good job. Congratulations and thank you.
Peter you have some of the best info on the web about this kind of stuff. Most folks will show you a fixed radio and blown finals with zero in between. Do you have a video describing TX and RX function? How they work? Near as I can tell when you key the mic, RX is somehow miraculously turned off while the key is down and TX is turned on. What got me into this is an RK 56 mic and an SRA 239. Both failed after hitting the concrete patio fairly hard. I take my Stryker 955 out of my dump truck every evening and sometimes getting into the front door with everything is a bit of a struggle. On both mics there is continuity all the way through from the plugs to the switches. They both bump the meter when keyed up but there is no audio.
Is this guy's videos AWESOME or what? this Extra class says every new ham should watch this kind of stuff for inspiration to persue the hobby. Great work with excellent explanation of how and why things work. Profs to TRXBench !!!!!
Hello-- There was a minor confusion in your explanation of the set-up of the bias voltages. In the video, you used the term "buyer's voltage". It took some time for me to realize that you were saying "bias voltage". LOL Very funny, on my part. Very nice video, and very well done. The importance of a good visual is shown here.
Hi Peter I wonder if the setting of the BIAS current with a modification similar to ICOM radio were you have a switch were you can set the BIAS independently and select the switch to centre position puts both Transistors in circuit as you showed with your componate tester the transistors were the same with slight difference of ma reading another success well done :)
great video's learn a lot from them. i have a dx-98vhp that keys up works on ssb but has no audio on AM put it in pa i hear audio coming out of the speaker and i have put the talkback on and there's audio coming out have you ever ran into a radio that had the same problem before? i am not sure what i'm missing to fix the problem.
i think here work 50 years of expirence ... Anyone change the circrit and then down. The regulation part often not in focus. .here we can learn some thing. Nice Videos thx!
It would have been interesting to measure those gate voltage points and see if they matched the spec for bias current adjustment and whether they were within 0.6%. I assume the voltage measure procedure was because of the change from the BJT to the FET? In the late 1970s CB craze you needed boxes of 2SC2312 and the other Mitsubishi outputs. Rotten co-ax and antenna work and high reflected power meant lots of dead rigs.
+Peter Walker Hi Peter, I'm not entirely sure but for me it looks like that is a time reduction in production. But as long you do not know if your FET's are matched it is a blind fly. So that is the reason why I have chosen the current method. 73
DTC114Ys is a digital transistor. If you can't get you can use a 2N5815 and put a 10K resitor in line with the base and a 47K resitor between base and emitter. hope that helps 73
Hi Peter I found part2 as you say setting the bios of the transistors are very tricky well done another success and another happy customer :) though it was funny about that power pot it shorted out the radio it is a joy to watch you fault finding and you need to have the right equipment before you tackle anything thanks once again :)
Again, thank you John
I am so happy TRX! I fixed my Stryker 955 after 2 months of down time. There is no one close by to work on it.
The closest guy is D-Rail 2 hours away and don't take mail in and is not open Weekends.
The 1st Audio amp TDA2003V that I put in died quickly because of a burned SMD FET on the Ground side of the speaker circuit that I found later. Also found a missing SMD resistor that provided chassis ground to the speaker.
All this because I repaired my speaker plug. One strand of positive copper wire got soldered to the negative and I failed to see it. Poor cutters left one strand that didn't get cut.😃
Thanks so much for these videos.
Great to watch and lots to learn .
I hope that is a bit what you was looking for.... Thanks for the feed back
The Schematics that you have seem so much better than what I can find for my Stryker 955.
sometime scans are simply bad...
@@TRXLab The Stryker 955 schematicas are clear as bell its just that so many things connect to one global path that runs throughout the radio. Its hard to trace things from end to end. And of course very few voltages are listed and no block diagram. Of course you could probably make worlds more sense out of it than I can. 🤣😃
Thank you so much for your time in making these great videos. I learn so much from you that I could not grasp from books.
Jimz Custom Radios Hi Jim, thanks for your feed-back. I'm glad that my Videos are usefull for you.
Hello again,
This time, thanks to your video've learned a lot and now I could fix swje CB-radio, which was damaged in AM......
You did a good job. Congratulations and thank you.
Very good repair and very enjoyable to watch. Please make more.
technos123 I'm still glad that you like it!! Thank you. 73
Peter you have some of the best info on the web about this kind of stuff.
Most folks will show you a fixed radio and blown finals with zero in between.
Do you have a video describing TX and RX function? How they work?
Near as I can tell when you key the mic, RX is somehow miraculously turned off while the key is down and TX is turned on.
What got me into this is an RK 56 mic and an SRA 239. Both failed after hitting the concrete patio fairly hard. I take my Stryker 955 out of my dump truck every evening and sometimes getting into the front door with everything is a bit of a struggle.
On both mics there is continuity all the way through from the plugs to the switches.
They both bump the meter when keyed up but there is no audio.
Is this guy's videos AWESOME or what? this Extra class says every new ham should watch this kind of stuff for inspiration to persue the hobby. Great work with excellent explanation of how and why things work. Profs to TRXBench !!!!!
satellite_guy wow what a feed back! Thank you :-)
Thanks for these very informative videos
Your work is appreciated.
73
Hello-- There was a minor confusion in your explanation of the set-up of the bias voltages. In the video, you used the term "buyer's voltage". It took some time for me to realize that you were saying "bias voltage". LOL Very funny, on my part.
Very nice video, and very well done. The importance of a good visual is shown here.
Wonderful job, thanks for sharing...
Thanks, its a pleasure.
Great video just came across this as I was looking for more or your videos
***** Hi Dennis, I try to fill the pipeline :-).. Thanks again, buddy!
Hi Peter I wonder if the setting of the BIAS current with a modification similar to ICOM radio were you have a switch were you can set the BIAS independently and select the switch to centre position puts both Transistors in circuit as you showed with your componate tester the transistors were the same with slight difference of ma reading another success well done :)
great video's learn a lot from them. i have a dx-98vhp that keys up works on ssb but has no audio on AM put it in pa i hear audio coming out of the speaker and i have put the talkback on and there's audio coming out have you ever ran into a radio that had the same problem before? i am not sure what i'm missing to fix the problem.
i think here work 50 years of expirence ... Anyone change the circrit and then down. The regulation part often not in focus. .here we can learn some thing. Nice Videos thx!
Thank you Karsten but only 40 years lol.
It would have been interesting to measure those gate voltage points and see if they matched the spec for bias current adjustment and whether they were within 0.6%.
I assume the voltage measure procedure was because of the change from the BJT to the FET?
In the late 1970s CB craze you needed boxes of 2SC2312 and the other Mitsubishi outputs. Rotten co-ax and antenna work and high reflected power meant lots of dead rigs.
+Peter Walker Hi Peter, I'm not entirely sure but for me it looks like that is a time reduction in production. But as long you do not know if your FET's are matched it is a blind fly. So that is the reason why I have chosen the current method. 73
Good Video. Thanks!!
The ERF2030 can be Replaced with a IRF520.....
Thanks for sharing!
Andy Tobin you are welcome :-)
I assume that you applied heat sink compound to the output transistors before mounting them.
Michael Swindal Hi Michael, yes of course :-)
TRXBench Thanks for all of your infomrative videos. Your attention to detail, and apparent patience, are quite unusual.
BTW
The reason they are called *_FET_* is because that is the noise they make when they blow!
:-)
+Peter Walker LOL, very nice
another good video, if you ever get to do any work on a yaesu 450d id like to see that as an owner of that radio.
+Glynn H Hi Glynn, thank you. If a 450 will come across I promise I do a video but not many in the field I believe... All the best 73
Great job, very nice video !!! Compliments... I have seen all videos, you are great !!!
73s de Pas IW0HEX
Pasquale IW0HEX Thanks for your feed-back!
Got a question - do you by chance know a transistor that will replace a ranger TDTC0114YS Transistor for AM Detector?
DTC114Ys is a digital transistor. If you can't get you can use a 2N5815 and put a 10K resitor in line with the base and a 47K resitor between base and emitter. hope that helps 73
Thank you very much.
CAN SOMEONE SHOW A VIDEO. HOW TO REPAIR A COBRA 29LTD THAT DOESN'T TRANSMIT AND RECEIVE PLEASE THANK YOU
show how to fix no receive on a cobra 29
Hi James, well if I would have a cobra 29 on had, but I don't. Sorry. 73
I can send u one ..lol