@BowWowPewPewCQ my name is Paul. I am watching MikesRadioRepair RUclips video to really put my best foot forward and put in an honest effort to learning about testing two radios. At approximately 8:32 I hear that the "left terminal of the mosfet is connected to ground or the ground plane and the lead is sort of hovered over that area of what looks like to me as the "circuit board" okay, so, since I am not sure if the brand of CB transceiver I will be working on will have the same final transistor or not, in other words I am trying to say "how would I now for sure, when working on another but similar chassis that the same place on the circuit board is ground or ground place area, they look quite similar but they all seem to work a little bit different" Do you think that it is okay if I send MiesRadioRepair an email asking a question to this effect? cause I really want to get a making noticeable performance improvements! One thing I was thinking is that maybe, if I get a toll free 1-800 number from an owner's manual I can call directly and ask questions to someone who answers the telephone call.? Maybe it is great because they may know that particular brand and they can walk me through it such that I can see and hear ally noticeable results. I don't mean to like make the volume go so loud that it is obnoxious or it disturbs everyone in the community and so forth but I guess what I am trying to say is or the word I am trying to get it is that I have a sense of accomplishment from working the CB radio and that the the other are on the channel or band notice a difference! I am not sure how to express it otherwise. Once upon a time I was in a shop in Buffalo New York America and I could here a very noticeable difference and big signal out of an amateur radio once, I guess i will call the shop keeper worked on the radio. Really big signal readings on the S/RF meter and loud volume. i partially get scarred when the signal are really loud out of the speaker when I am by myself like I will get in trouble for disturbing people, but I do not wat to do that, that is not my intent. I guess I sort of want a purpose, it is funny why would I think about "performance improvements" I think that way equipment is manufactured and made is really great the way that it is!!! However, I think that deep inside I could contribute to radio gear and such. Well I thought I would just run this buy you and I will send the same thing to MikesRadioRepair in the email that I see the best I can in RUclips.😀🧑🔧🐾🐿🌎🏁
Thanks Mike for all your videos and help! I installed new mosfets and ran into a problem on AM with the Lincoln II plus and just a few minutes before finishing your vid I found a blown Tip36 lol!! I was lucky with the ferrite as all I had to do was tack it back in place. Thanks again!!
I guess im randomly asking but does any of you know a tool to log back into an instagram account? I was stupid forgot the login password. I love any help you can give me.
@Cade Thomas I really appreciate your reply. I got to the site thru google and I'm in the hacking process now. Looks like it's gonna take quite some time so I will get back to you later when my account password hopefully is recovered.
Mike is absolutely the best Tech ! Old school sense and more importantly knowledge, and he is genuinely a cool guy. My unending problem is how in the world does a person, potential customer contact him ??? any help here would be monumental !! Thanks !
Forget it. He quit responding entirely. I was a frequent customer and he repaired several radios for me. Then he quit responding and no one has been able to contact him.
On my Lincoln 2+ I moved my AM regulator to the back where the heat sink is. When it was on the side, it would get hot hast. I put a new Tip-36 on the back and it’s night and day difference. The regulator and the finals run nice and cool. That was about 2 years ago. No problem since.
Thanks Mike for addressing the Maxima mod. There is a certain RUclips or self-proclaimed CB guru that preaches the radios gnocchi up without the max mod and I’ve always thought he was full of BS so I appreciate your addressing that with a commonsense approach.
I had the same issue with a stryker 655 a guy brought in the shop and he actually admitted his antenna was bad. When it went took out the finals and tip36.
I have noticed several videos on blown finals. Many of the videos involve the President Lincoln II. I recently acquired a Lincoln II. Guess what? I blew the finals out. I've been into radio's for 20+ years and never ruined a radio. My swr was 1:4 and I have current chokes in line at the radio, shack entrance and at the antenna. My Lincoln had the 1310n transistors. I shipped it off and I was advised to go with better transistors.
Good crash course on radio electronics. I wish I had the attention span to learn electrical engineering. I would have a lot of old electronics that would be virtually immortal.
I did radio years ago.... Please note that you can tune your antenna on a specific channel. If you set it on channel 40, channel one will probably be higher. The best spectrum spread is to tune on channel 19 or 20. this is why truckers run channel 19.
what shit are you talking about ?? so why don't truckers run on 20 if that's your logic.. in fact if you take in to account the 'alpha channels truckers would use channel 22 or 23 as center of the CB spectrum 26.965 to 27.405 is channel 22.5 or 27.230Mhz. run on channel 19....ass..
Compare the lowest channel, 1, against the highest, either 23 or 40. Adjust the antenna(s) accordingly. Adjust dual antennas at the same time, not individually.
ALWAYS TUNE YOUR ANTENNA BEFORE PUTTING A RADIO IN SERVICE. Never trust the internal SWR circuitry. It lies, it lies and it lies. Use a good external SWR meter. One that has not been dropped and broken the solder connection inside of the box. 25 - $55.
Thanks for these videos Mike, i have learned a lot. Going through them again, i think i missed a couple of them.
Месяц назад
A 1 to 1 baulin in the coax can also prevent a lot of the SWR from getting back into the radio because it acts as a reflexive point that will bounce a large part of the reflected power from the antenna back to the antenna.. Is it a substitute for a good matched antenna? NO but it can help a marginal antenna from becoming a bad antenna.. There are lots of conditions that can detune an antenna like heavy rain, ice, fog etc. that are temporary but if you use your radio in those conditions often it is something to think about.. several wraps of coax thru a ferrite core can get you there..
I have always known about the SWR since I started using the radio, however I never knew exactly what finals were. I definitely learned something here. Thanks
Had that experience. Basically, I've burned the output stage of an RF PA that I've made, due to a badly tuned antenna. Funnily, the PA is only capable of outputting 1W at best, and I was not expecting it to be damaged.
Why does everyone who know a little bit, like to dis a guy who makes a video for those that don’t know this? Be nice or be quiet and click on another video. Thank you for the video and the time you spent for some.
Good work ..👍thank you for the video .../// my mike is burn ..the cause false connection 🥺on my president jackson ..40 chanel...inf/sup etc but my square microphone don't answer ..i got to repair it...i slowly learn...
Just a reminder to those who make their own coax cables: Coax, (especially the foam core), can suck in water like a fish. It's amazing how much water can wick into your cable if it's not properly sealed. You can generally tell this is happening if your SWR is good on a dry day and they goes wonky after it rains. Then it dries out and your SWR is good again. Chances are you have water in the line or your antenna itself has some water intrusion somewhere. So make sure your antenna system is SEALED. The coax is overlooked and skimped on 99.9% of the time. Waterproof all connectors. You can use Mastic tape on connections you may want to remove later. Just make sure and SEAL it. Also routing your cable out of the direct weather is a good idea (under your house eave, car hoods, etc). Little exposure as possible. For underground runs, I put mine inside electrical-grade conduit for extra protection. A little extra work and expense, but It's cheap insurance. It also helps if you find yourself digging later around your coax. You'll hit the conduit first and not damage your coax. I also like to use heat shrink (the type with the glue inside) to seal where the coax enters the connector. I don't rely on the solder alone for sealing. Get GOOD GRADE heat shrink. Not that cheap Rat-Shack, Harbor Freight thin garbage. Get the 2 or 3:1 stuff with the heavy glue. This stuff will seal just about anything. Likewise it's tough to remove so be sure your solder and coax tests out OK before you install the shrink.
I remember years ago, operators stating that their match would improve in the rain. I never tried to disprove or prove that because I never gave it much thought. Recently I have learned the importance of sealing the coax and the connection that faces the weather on a daily and nightly basis.
Self amalgamating tape is is good also, especially if you live in a area with destructive birds that like chewing on coax ends. Though usually they are that particular, gotta chew it all in some parts of the world.
I have a K40 trunk lip Mount antenna hooked up to my Stryker 447 radio and my SWR on it on Channel 1 is 1.1 and on channel 20 is a 1.2 and on channel 40 is a 1.7 but for some reason I can't hear anybody on it for some reason and I live really close to the highway where there's tons of semi trucks rolling down it but I still can't hear anybody talking could that mean that my antenna has something wrong with it
SOUL MAN, it sounds like you have the exact same issue that I have with my Stryker 955HP. Years ago I used it while driving tractor-trailer and had a few occasions where SWR peaked to the limit due to bad antenna connection. Not sure if that was the cause, but the last year I used it & ever since, I can't receive nearly anything on that radio even tho I'm in an area by the highway there should be plenty of CB activity. I just hooked it back up this week and it's still 'far too quiet'.
@@ColtTSMG I figured out what was wrong with my Stryker Sr 447 my antenna is a trunk lip Mount K40 antenna and it wasn't grounded right but then I got it grounded right and it works great now I'm receiving and transmitting very good and they SWR is down to a 1.1 on all the channels and on Channel 40 it is 1.2 my SWR is now so I'm receiving good and transmitting but I'm still upgrading my antenna to a striker Sr A10 antenna I already ordered one but the u.s. Postal Service lost mining during shipping so now I'm waiting on the US Postal Service to replacement hopefully they are send me a new one other than that my radio is working out great now so you might want to check and make sure that your antenna is grounded cuz that could be your issue as well
I'm trying to set up a really old set , Midland . 50ohms impedence ? Hmm , I've heard that be fore . Impedence is resistance . But you still need a opposite polarity reflecter for antanna to work ( I think) . Just don't short it . Broken coax . Splices will cause problems too .
Can the method you used to check the final be used on older radios? I've got a Robyn SB 520D with weak (if any) tx output. I didn't see any other damage. Would it be a good idea to replace the AM regulator also?
Great job as always Mike. Just curious if those finals were good what would the foward and reverse resistance be? Thank you for sharing your info on radio repair!
That's exactly what I was looking for in the comment section...what the reading would be had the finals not blown? Please let us know! Thanks again Mike for sharing your knowledge with us! Brian
I had a lighting strike one of the antennas that I had up. I had my ham radio unhooked. but I had a free play radio and a am drake which both got hit by the lighting. magic smoke came out of the drake. still got it around here some where. after it killed those two radios. it by passed the big screen i had bought was fine but it went on past and fried the misses computer. go figure.
I love your videos. I learn a lot about radio from watching your content, thank you. Question - if the finals get blown so frequently, and pass on current for more internal damage... shouldn’t they build in a fuse?
Question about the finals, I know that the 2sc1969's would need to be a matched pair, but do mosfets for example, irf520's need to be a matched pair? I'm still learning all this stuff, thanks.
@@mikesradiorepair np Mike! I know you're busy, I just want to say thanks for your detailed videos. From reading schematics to using test equipment, I've learned a lot just watching. One of these days I'll own the essential pieces of test equipment so I can maintain my collection of radios. (70's-90's) Just for alignments.
The MFJ Antenna Analyzer (259 or 269) is the best money that a new Ham can spend, IMO. Say what you will about MFJ, but this piece of gear is worth it's weight doing antenna work.
Now, if I could make heads or tails of my switching power supply layout vs. schematics to fix it. It blew out the mosfets... strange because it is supposed to have overheat, over current, over voltage protection, but when doing testing using it, it overheated and did puff the magic dragon on me. I have replaced those, but the supply is stuck in protection mode, and I'm at an impasse. Alinco DM330MVT
There is a project but to see the signal strength that the radio is receiving, for example, a weak but audible international station lights up 2 LEDs and one is coming in strong as if it were local, lights up 5 LEDs for a radio receiver. Do you know or have a project like this?
I had some serious damage done to my Anytone 5555N it have 3x 13n10 but the board looks the same as yours, the TIP36S was burning hot even when not transmitting, it just happend a morning i turned on the radio while i key the mike the display got dim and the radio basicly turned of untill you released the button. It even melted the fuseholder. I saw some one talk about those 13n10 are bad, and recommend to replace them with IRF520's - anything else to replace?
Mike, thank you for the videos, they're so helpful. Just curious, can you test the AM regulators and the drivers the same way you tested the finals? I'm trying to find out why a Cobra 25 LTD Classic won't transmit or receive. (I already checked the cb/pa switch and caps esr.) The sound chip makes noise when I put my finger on it. The signal meter isn't moving, but it's not "stuck", it moves freely - doesn't move when receiving signal is being broadcast. In the rear of the 25 there are two transistors. The one near L12 is the final, but what is the one in the very rear corner and what is the one by the volume/on/off switch? Thanks!!
When you say does not transmit, you mean you have a dead key but no audio ?? The audio chip on the side of the chassis might be your issue. The 29 and the 25 radios DO require those 2 thick rubber washers between the mount bracket and the case of the radio.... If their not in there then when you tighten the 2 knobs they pull the case away from the PCB slightly and the solder joints fail.... Example no receive in the speaker and no audio going out....I have seen that a few thousand times....
@@cajuncoinhunter Thank you for writing back. If you watch this video someone posted, this is exactly what happens with my Cobra 25 LTD...it's easier to watch his video than me trying to explain it, but everything that happens in his video is what happens with my 25 LTD...here's the link for you: ruclips.net/video/nzqjIKUKBsg/видео.html
I’m having problems with my SWR high it goes to three no matter which way I put it on channel 1- through 40 still stays the same three I can’t get it down I checked the coax coax is fine the ground it’s fine but how can you tell if the antenna I have a trucker 2000 I’m thinking he’s got some kind of a gram problems on the van I have it on the van back of the van
It seems like radios have some resistance to "blowing" finals. Even when presented with high SWR. I have keyed my CB before with out an antenna screwed in. On accident. And I don't think I blew the finals. Over time, I would imagine running a high SWR will eventually blow finals.
Depends on the reactance and impedance the radio is looking at ,the reflected power is generally misunderstood as causing radio failure but infact adds to the forward power back to antenna
In you professional opinion. I have an old Cobra 40 channel cb, LTD I think it was, that I used for 20 + years trucking. I spent over 35 years OTR & this was my 3rd radio. It has been boxed away for a dozen years or so. Are these worth going through, checking out & repairing if need be or is it better to buy something new. Just want to put it in my pickup just to have when I am on the road with my horses. Also I live on top of a mountain so I would like to see if it is like it was years ago where you hit the skip & could talk a long ways off. Just something to have some fun with. Also thought about hooking a linear to it. What's a good antenna these days? I always liked the K40's but didn't know if anything else is better. If I do what I am thinking of it will be mounted in a Dodge pickup. Thanks for your time.
I have a galaxy 33hml and I checked from the ground on the transistor to the opposite side and had continuity between them on both and it didn’t matter which lead I used on the ground but there was no continuity from ground to the middle of the transistor. Does that sound burnt to you?
Any repair tips for fixing a STANDARD ECLIPSE GX1245S VHF Marine radio? Current draw is 600 mAmp. Display is blank but the illumination light is lit. Haven't been able to locate a schematic. Service manual is MMGX1240S (covers GX1240/1245 models ). Thank you for any info you may provide.
I don't have a schematic for it, own one and have never worked on one but if the final is bad that's probably all it needs. I would probably probe around with a oscilloscope first to verify it's the problem and if it is take some voltage measurements. Basic troubleshooting.
I'm having issues... radio was just fine and tuned... I woke up n boom cobra lights changed double red screeching when I hit the mic and my dome lights flicker when I press the mic... it definitely possessed... nothing changed in set up or antenna.. fuse is fine it recieves good but omg the screeching like the mic is getting feedback from the speaker screeching...
I have a Cobra 29 soundtracker in my truck and I recently put speakers headlamps in my truck and now my RF reflection is really high how do I get it back down
Mike, I have a dual band amateur radio I picked up second hand from another ham who said the UHF side of the radio no longer worked due to a shorted N to SO239 adapter. The radio still works fine on VHF and receives UHF fine. With an analog watt meter into a dummy load, I can see the needle just barely lift off 0 while in low power UHF, but if I key the radio on high power it blows the 15 amp inline fuse before I can see anything happen. Do you think replacing the Mitsubishi ra60h3847m1 PA module would potentially fix this radio or has more damage been done that I cannot properly diagnose or detect? I am having a hard time finding any information about testing PA modules and was hoping to find a way to test with a multi meter like you show in the video. RF in, Gate voltage and Drain voltage all short to ground with high resistance while RF out does not short at all and the meter reads OL. Is that a sign that the finals have fail and are no longer letting RF through the PA module? Any help or comments would be greatly appreciated.
I have a friend who checks his SWR off the radio and it is great. He is a ham operator and when he runs an amplifier it shows a much higher SWR. Should he be concerned or disregard the reading and only go by the. "barefoot" reading?
Yes, he should be concerned. When you are running a amplifier you need to place a SWR meter in two places, between the radio and amplifier and another between the amplifier and the antenna.
They used to make an SWR meter with a built in Pi-L network (transmatch) you could install to regulate SWR. I use one to go from 10 meter to 11 meter on the same antenna.
I have a RK5640a running a Wilson 2000 on a 18 ft Wilson cable running for a few years w/0 SWR all the sudden it started crackling when receiving transmissions but I was able to transmit fine two days ago it just stopped receiving and transmitting all together thought cheap radio lasted longer than I expected however now I've installed two brand new radios both same issue seems when I go to calibrate it starts working normally and then the needle shoots back and forth a few times and then down to nothing no response the rx/tx lights up antenna lights off and no responses from the R/RF,SWR,CAL settings I'm puzzled could it be a bad antenna/cable killing these radios?
Yes it could. You may have a intermittent short. If the coax cable is routed through a door jamb the cable may have become crushed. Depending on what type of antenna you have I have seen loading coils fill up with water.
![[#2024MAMA] ROSÉ (로제), Bruno Mars - APT. | Mnet 241122 방송](http://i.ytimg.com/vi/dgGqD28J6aQ/mqdefault.jpg)
After just watching a video claiming this can't happen it was refreshing to come back to reality. Great explanation.
@BowWowPewPewCQ my name is Paul. I am watching MikesRadioRepair RUclips video to really put my best foot forward and put in an honest effort to learning about testing two radios. At approximately 8:32 I hear that the "left terminal of the mosfet is connected to ground or the ground plane and the lead is sort of hovered over that area of what looks like to me as the "circuit board" okay, so, since I am not sure if the brand of CB transceiver I will be working on will have the same final transistor or not, in other words I am trying to say "how would I now for sure, when working on another but similar chassis that the same place on the circuit board is ground or ground place area, they look quite similar but they all seem to work a little bit different" Do you think that it is okay if I send MiesRadioRepair an email asking a question to this effect? cause I really want to get a making noticeable performance improvements! One thing I was thinking is that maybe, if I get a toll free 1-800 number from an owner's manual I can call directly and ask questions to someone who answers the telephone call.? Maybe it is great because they may know that particular brand and they can walk me through it such that I can see and hear ally noticeable results. I don't mean to like make the volume go so loud that it is obnoxious or it disturbs everyone in the community and so forth but I guess what I am trying to say is or the word I am trying to get it is that I have a sense of accomplishment from working the CB radio and that the the other are on the channel or band notice a difference! I am not sure how to express it otherwise. Once upon a time I was in a shop in Buffalo New York America and I could here a very noticeable difference and big signal out of an amateur radio once, I guess i will call the shop keeper worked on the radio. Really big signal readings on the S/RF meter and loud volume. i partially get scarred when the signal are really loud out of the speaker when I am by myself like I will get in trouble for disturbing people, but I do not wat to do that, that is not my intent. I guess I sort of want a purpose, it is funny why would I think about "performance improvements" I think that way equipment is manufactured and made is really great the way that it is!!! However, I think that deep inside I could contribute to radio gear and such. Well I thought I would just run this buy you and I will send the same thing to MikesRadioRepair in the email that I see the best I can in RUclips.😀🧑🔧🐾🐿🌎🏁
Sure miss you real banter and no BS chat Mike, hope you are well and enjoying life.
Care sent.
Hey there. This may be a shot in the dark but, can you tell me the proper avenue to contact Mike??
No one , and I mean no one knows.😢 thanks. Mark.
Thanks Mike for all your videos and help! I installed new mosfets and ran into a problem on AM with the Lincoln II plus and just a few minutes before finishing your vid I found a blown Tip36 lol!! I was lucky with the ferrite as all I had to do was tack it back in place.
Thanks again!!
I guess im randomly asking but does any of you know a tool to log back into an instagram account?
I was stupid forgot the login password. I love any help you can give me.
@Spencer Alfredo Instablaster :)
@Cade Thomas I really appreciate your reply. I got to the site thru google and I'm in the hacking process now.
Looks like it's gonna take quite some time so I will get back to you later when my account password hopefully is recovered.
@Spencer Alfredo You are welcome :D
High swr on Lincolns or any radio with high watts Could be with cheap finals, 💥!! You are a good radio guy!!
Mike is absolutely the best Tech ! Old school sense and more importantly knowledge,
and he is genuinely a cool guy.
My unending problem is how in the world does a person, potential customer contact him ??? any help here would be monumental !! Thanks !
Forget it. He quit responding entirely. I was a frequent customer and he repaired several radios for me. Then he quit responding and no one has been able to contact him.
The price of repairing both radios was still less than half of what a new radio would cost.
Good to see you are still around on the platform, Mike.
Mike, how are you ? No radio repair? Please answer ! Fhanks!
On my Lincoln 2+ I moved my AM regulator to the back where the heat sink is. When it was on the side, it would get hot hast. I put a new Tip-36 on the back and it’s night and day difference. The regulator and the finals run nice and cool. That was about 2 years ago. No problem since.
Thanks Mike for addressing the Maxima mod. There is a certain RUclips or self-proclaimed CB guru that preaches the radios gnocchi up without the max mod and I’ve always thought he was full of BS so I appreciate your addressing that with a commonsense approach.
I'll trust MikesRadioRepair he's pretty good this guy is expert on radios just don't rush him.
I love your videos and greatful you take the time to explain what you do and why you do it. Cheers, 73's!
Thanks Max Mike! You at least tried to teach some of us to work on our stuff! 😃
My grandfather liked black walnuts. He used his workshop vice to open them.😅
I had the same issue with a stryker 655 a guy brought in the shop and he actually admitted his antenna was bad. When it went took out the finals and tip36.
What are the best antennas for this type radio?
@@justbeforethereturnofchris2393 CB antenna!
@@PeterDad60 .....yea I found one that works with this CB radio...
Thinks Mike for the great information. That first part was nuts ! No max mod for me. Thanks!
Love your humour Mike.
I drew inspiration from your method for how I publish my How-to- Fix videos.
I have noticed several videos on blown finals. Many of the videos involve the President Lincoln II. I recently acquired a Lincoln II. Guess what? I blew the finals out. I've been into radio's for 20+ years and never ruined a radio. My swr was 1:4 and I have current chokes in line at the radio, shack entrance and at the antenna. My Lincoln had the 1310n transistors. I shipped it off and I was advised to go with better transistors.
Good Advice.......Customer wanted "Fars" but only got "Swrs" !!! ......Whoever messes with Coax or Antenna better check Reflected Power.....
Good crash course on radio electronics. I wish I had the attention span to learn electrical engineering. I would have a lot of old electronics that would be virtually immortal.
Were is mike ???, he is needed !!!!!
Come back to you tube,Mike . I need some radio work done…
Very useful Tips.
I wish you lived in the Uk, I have a High Gain 5 I really need tuned and setup.
It works, and had the channel Mods done on it.
Hi poss may be able to help with sorting your Hygain 5 radio
Can e mail me on mrianjones@live.co.uk
Thanks for the video Mike great info.
I did radio years ago.... Please note that you can tune your antenna on a specific channel. If you set it on channel 40, channel one will probably be higher. The best spectrum spread is to tune on channel 19 or 20. this is why truckers run channel 19.
what shit are you talking about ??
so why don't truckers run on 20 if that's your logic..
in fact if you take in to account the 'alpha channels truckers would use channel 22 or 23 as center of the CB spectrum 26.965 to 27.405 is channel 22.5 or 27.230Mhz.
run on channel 19....ass..
They ran 19 back when it was only 23 channels. 11 was a calling frequency, and of course, 9 was for emergencies.
That's probably why 9 was for emergencies because it was a mid spectrum channel when they were 23 channel
Compare the lowest channel, 1, against the highest, either 23 or 40. Adjust the antenna(s) accordingly. Adjust dual antennas at the same time, not individually.
ALWAYS TUNE YOUR ANTENNA BEFORE PUTTING A RADIO IN SERVICE. Never trust the internal SWR circuitry. It lies, it lies and it lies. Use a good external SWR meter. One that has not been dropped and broken the solder connection inside of the box. 25 - $55.
Thanks for these videos Mike, i have learned a lot. Going through them again, i think i missed a couple of them.
A 1 to 1 baulin in the coax can also prevent a lot of the SWR from getting back into the radio because it acts as a reflexive point that will bounce a large part of the reflected power from the antenna back to the antenna.. Is it a substitute for a good matched antenna? NO but it can help a marginal antenna from becoming a bad antenna.. There are lots of conditions that can detune an antenna like heavy rain, ice, fog etc. that are temporary but if you use your radio in those conditions often it is something to think about.. several wraps of coax thru a ferrite core can get you there..
I have always known about the SWR since I started using the radio, however I never knew exactly what finals were. I definitely learned something here. Thanks
Very nice shared ideas that helps...!
Your video's are excellent and very informative.
Alan in the UK
Had that experience. Basically, I've burned the output stage of an RF PA that I've made, due to a badly tuned antenna. Funnily, the PA is only capable of outputting 1W at best, and I was not expecting it to be damaged.
I run a Francis 5.5ft whip on my truck and the SWR is 1.0 on my Lincoln II+
Thank you for your sage advice
i remember getting "suspect " output transistors that had the numbers either blacked out with a felt pen, or sanded off! lots of magic smoke!
Why does everyone who know a little bit, like to dis a guy who makes a video for those that don’t know this?
Be nice or be quiet and click on another video.
Thank you for the video and the time you spent for some.
Maybe they think the info is incorrect
Thanks for letting people know about the Max Mod ripoff! I've been trying to tell people for years about that scam. Well done!
I love your ability to teach me radio repair you explain it I understand it ! ps Im an auto obd tech my nails look worse than yours!
I wish you'd come back
Good work ..👍thank you for the video .../// my mike is burn ..the cause false connection 🥺on my president jackson ..40 chanel...inf/sup etc but my square microphone don't answer ..i got to repair it...i slowly learn...
any thing over three . start checking the antenna or coax.. one point five you can live with one to one is best.
I love it good
Keep uploading videos like this
From as radio guy, just remember a SWR meter "measures" swr, it doesn't fix it. it's not a tuner (they sell tuner's separately)
Wise words as usual Mike!
Great TIPs Mike. No pun intended.
Thanks for showing!
Great info. ✌✌
please tell me you could still fix my radio!
Just a reminder to those who make their own coax cables:
Coax, (especially the foam core), can suck in water like a fish. It's amazing how much water can wick into your cable if it's not properly sealed. You can generally tell this is happening if your SWR is good on a dry day and they goes wonky after it rains. Then it dries out and your SWR is good again. Chances are you have water in the line or your antenna itself has some water intrusion somewhere.
So make sure your antenna system is SEALED. The coax is overlooked and skimped on 99.9% of the time. Waterproof all connectors. You can use Mastic tape on connections you may want to remove later. Just make sure and SEAL it. Also routing your cable out of the direct weather is a good idea (under your house eave, car hoods, etc). Little exposure as possible.
For underground runs, I put mine inside electrical-grade conduit for extra protection. A little extra work and expense, but It's cheap insurance. It also helps if you find yourself digging later around your coax. You'll hit the conduit first and not damage your coax.
I also like to use heat shrink (the type with the glue inside) to seal where the coax enters the connector. I don't rely on the solder alone for sealing. Get GOOD GRADE heat shrink. Not that cheap Rat-Shack, Harbor Freight thin garbage. Get the 2 or 3:1 stuff with the heavy glue. This stuff will seal just about anything. Likewise it's tough to remove so be sure your solder and coax tests out OK before you install the shrink.
I remember years ago, operators stating that their match would improve in the rain. I never tried to disprove or prove that because I never gave it much thought. Recently I have learned the importance of sealing the coax and the connection that faces the weather on a daily and nightly basis.
Very good post... Very well said. Listen to this guy; he knows his stuff...
Self amalgamating tape is is good also, especially if you live in a area with destructive birds that like chewing on coax ends. Though usually they are that particular, gotta chew it all in some parts of the world.
I have a K40 trunk lip Mount antenna hooked up to my Stryker 447 radio and my SWR on it on Channel 1 is 1.1 and on channel 20 is a 1.2 and on channel 40 is a 1.7 but for some reason I can't hear anybody on it for some reason and I live really close to the highway where there's tons of semi trucks rolling down it but I still can't hear anybody talking could that mean that my antenna has something wrong with it
SOUL MAN, it sounds like you have the exact same issue that I have with my Stryker 955HP.
Years ago I used it while driving tractor-trailer and had a few occasions where SWR peaked to the limit due to bad antenna connection. Not sure if that was the cause, but the last year I used it & ever since, I can't receive nearly anything on that radio even tho I'm in an area by the highway there should be plenty of CB activity. I just hooked it back up this week and it's still 'far too quiet'.
@@ColtTSMG I figured out what was wrong with my Stryker Sr 447 my antenna is a trunk lip Mount K40 antenna and it wasn't grounded right but then I got it grounded right and it works great now I'm receiving and transmitting very good and they SWR is down to a 1.1 on all the channels and on Channel 40 it is 1.2 my SWR is now so I'm receiving good and transmitting but I'm still upgrading my antenna to a striker Sr A10 antenna I already ordered one but the u.s. Postal Service lost mining during shipping so now I'm waiting on the US Postal Service to replacement hopefully they are send me a new one other than that my radio is working out great now so you might want to check and make sure that your antenna is grounded cuz that could be your issue as well
Good video ☺️
I'm trying to set up a really old set , Midland . 50ohms impedence ? Hmm , I've heard that be fore . Impedence is resistance . But you still need a opposite polarity reflecter for antanna to work ( I think) . Just don't short it . Broken coax . Splices will cause problems too .
Higher swr causes the finals to heat up more they go into thermal overload.
Can the method you used to check the final be used on older radios? I've got a Robyn SB 520D with weak (if any) tx output. I didn't see any other damage. Would it be a good idea to replace the AM regulator also?
This is exactly what happened to my new Lincoln II+
Great job as always Mike. Just curious if those finals were good what would the foward and reverse resistance be?
Thank you for sharing your info on radio repair!
That's exactly what I was looking for in the comment section...what the reading would be had the finals not blown? Please let us know! Thanks again Mike for sharing your knowledge with us! Brian
I like smoke 😅😅😅
How I can ship a radio for some updates mod...Pls lets me know...Thanks
Very informative video, Thank you!
Excellent video! I have about four old radios laying around I think this will fix! Thank you so much, and I just subscribed.
Thank you.
I had a lighting strike one of the antennas that I had up. I had my ham radio unhooked. but I had a free play radio and a am drake which both got hit by the lighting. magic smoke came out of the drake. still got it around here some where. after it killed those two radios. it by passed the big screen i had bought was fine but it went on past and fried the misses computer. go figure.
I love your videos. I learn a lot about radio from watching your content, thank you. Question - if the finals get blown so frequently, and pass on current for more internal damage... shouldn’t they build in a fuse?
Read the support boards for the ubitx theres a nice protection mod using a P-FET like the IRF9540 as finals draw power from the 12volt input
Which mosfets do you like to use for replacements? I see some TIP36C from galco but looking for the FQP13N10 mosfets and there are so many options.
Question about the finals, I know that the 2sc1969's would need to be a matched pair, but do mosfets for example, irf520's need to be a matched pair? I'm still learning all this stuff, thanks.
Yes they do.
Hey, I just bought a new antenna, but my radio is acting up. Can I borrow yours to check it out........
Sorry but I don't loan equipment, even to people I know.
@@mikesradiorepair haha sorry Mike. My humor's a little dry. Just trying to sum up the video in a couple words.
@@JAWS1376
LOL, it went right over my head. Now that I look at it again I get it. Sometimes things have a hard time penetrating my thick skull. :-)
@@mikesradiorepair np Mike! I know you're busy, I just want to say thanks for your detailed videos. From reading schematics to using test equipment, I've learned a lot just watching. One of these days I'll own the essential pieces of test equipment so I can maintain my collection of radios. (70's-90's) Just for alignments.
SWR stands for Standing Wave Ratio...how do you get SWR's? People do the same thing with RPM...pet peeve of mine I guess...
bit like when people say 73's...
Because he's a CBer.
Christ almighty...
All about the reflection
@James Marquis Don't try pushing your bullshit on me.
You can wash your hands with raw lemon juice…then your good 👍
The MFJ Antenna Analyzer (259 or 269) is the best money that a new Ham can spend, IMO. Say what you will about MFJ, but this piece of gear is worth it's weight doing antenna work.
Does anyone know what happened to Mike?
😢
Amazing information. My question is how much did the repair for those radios cost? Would such a repair be close to the price a new radio? Thank you.
Mike, I think I have the High Gain 5 Schematic, that I need to find and send you a copy of.
Thank you sir 👍
My cb gets power but doesn’t transmit or receive. Guessin I blew out a resistor in it. Cobra 29ltd. 4 years old.
Now, if I could make heads or tails of my switching power supply layout vs. schematics to fix it. It blew out the mosfets... strange because it is supposed to have overheat, over current, over voltage protection, but when doing testing using it, it overheated and did puff the magic dragon on me.
I have replaced those, but the supply is stuck in protection mode, and I'm at an impasse.
Alinco DM330MVT
Switch modes are like Morris the Cat, finiky ;) I've seen the coils change value and thus change the frequency and blow the mosfets!!!
I hope Horatio is okay!
There is a project but to see the signal strength that the radio is receiving, for example, a weak but audible international station lights up 2 LEDs and one is coming in strong as if it were local, lights up 5 LEDs for a radio receiver. Do you know or have a project like this?
I had some serious damage done to my Anytone 5555N it have 3x 13n10 but the board looks the same as yours, the TIP36S was burning hot even when not transmitting, it just happend a morning i turned on the radio while i key the mike the display got dim and the radio basicly turned of untill you released the button. It even melted the fuseholder. I saw some one talk about those 13n10 are bad, and recommend to replace them with IRF520's - anything else to replace?
Mike, thank you for the videos, they're so helpful. Just curious, can you test the AM regulators and the drivers the same way you tested the finals? I'm trying to find out why a Cobra 25 LTD Classic won't transmit or receive. (I already checked the cb/pa switch and caps esr.) The sound chip makes noise when I put my finger on it. The signal meter isn't moving, but it's not "stuck", it moves freely - doesn't move when receiving signal is being broadcast. In the rear of the 25 there are two transistors. The one near L12 is the final, but what is the one in the very rear corner and what is the one by the volume/on/off switch? Thanks!!
When you say does not transmit, you mean you have a dead key but no audio ?? The audio chip on the side of the chassis might be your issue. The 29 and the 25 radios DO require those 2 thick rubber washers between the mount bracket and the case of the radio.... If their not in there then when you tighten the 2 knobs they pull the case away from the PCB slightly and the solder joints fail.... Example no receive in the speaker and no audio going out....I have seen that a few thousand times....
@@cajuncoinhunter Thank you for writing back. If you watch this video someone posted, this is exactly what happens with my Cobra 25 LTD...it's easier to watch his video than me trying to explain it, but everything that happens in his video is what happens with my 25 LTD...here's the link for you: ruclips.net/video/nzqjIKUKBsg/видео.html
Yup, I know exactly what you mean about Walnut shells.
I’m having problems with my SWR high it goes to three no matter which way I put it on channel 1- through 40 still stays the same three I can’t get it down I checked the coax coax is fine the ground it’s fine but how can you tell if the antenna I have a trucker 2000 I’m thinking he’s got some kind of a gram problems on the van I have it on the van back of the van
It seems like radios have some resistance to "blowing" finals. Even when presented with high SWR. I have keyed my CB before with out an antenna screwed in. On accident. And I don't think I blew the finals. Over time, I would imagine running a high SWR will eventually blow finals.
Depends on the reactance and impedance the radio is looking at ,the reflected power is generally misunderstood as causing radio failure but infact adds to the forward power back to antenna
Will you please fix my 138xlr
😢
😢 I think he's now retired from repairs...so I'm told😢😢😢😢
Ahh 😢
In you professional opinion. I have an old Cobra 40 channel cb, LTD I think it was, that I used for 20 + years trucking. I spent over 35 years OTR & this was my 3rd radio. It has been boxed away for a dozen years or so. Are these worth going through, checking out & repairing if need be or is it better to buy something new. Just want to put it in my pickup just to have when I am on the road with my horses. Also I live on top of a mountain so I would like to see if it is like it was years ago where you hit the skip & could talk a long ways off. Just something to have some fun with. Also thought about hooking a linear to it. What's a good antenna these days? I always liked the K40's but didn't know if anything else is better. If I do what I am thinking of it will be mounted in a Dodge pickup.
Thanks for your time.
I have a galaxy 33hml and I checked from the ground on the transistor to the opposite side and had continuity between them on both and it didn’t matter which lead I used on the ground but there was no continuity from ground to the middle of the transistor. Does that sound burnt to you?
My antenna must have gone south and when I keyed up my Telsat 140 I lost receive and transmit. What should I look for ? Finals blown??
Any repair tips for fixing a STANDARD ECLIPSE GX1245S VHF Marine radio? Current draw is 600 mAmp. Display is blank but the illumination light is lit. Haven't been able to locate a schematic. Service manual is MMGX1240S (covers GX1240/1245 models ). Thank you for any info you may provide.
Sorry I do not have any service information on any marine or aircraft radios. You need a GROL license to service them which I do not have.
On an FM only radio Btech GMRS-50X1 if the final is burned out, is there any other component that should be premptively replaced?
I don't have a schematic for it, own one and have never worked on one but if the final is bad that's probably all it needs. I would probably probe around with a oscilloscope first to verify it's the problem and if it is take some voltage measurements. Basic troubleshooting.
I'm having issues... radio was just fine and tuned... I woke up n boom cobra lights changed double red screeching when I hit the mic and my dome lights flicker when I press the mic... it definitely possessed... nothing changed in set up or antenna.. fuse is fine it recieves good but omg the screeching like the mic is getting feedback from the speaker screeching...
Cobra 29 classic
Dome lights in truck
I've got a cobra lt 29 and I have one switch is bad how hard is it to change or fix
will this work on a uniden 510xl and the 520 xl
I have a Cobra 29 soundtracker in my truck and I recently put speakers headlamps in my truck and now my RF reflection is really high how do I get it back down
Mike, I have a dual band amateur radio I picked up second hand from another ham who said the UHF side of the radio no longer worked due to a shorted N to SO239 adapter. The radio still works fine on VHF and receives UHF fine. With an analog watt meter into a dummy load, I can see the needle just barely lift off 0 while in low power UHF, but if I key the radio on high power it blows the 15 amp inline fuse before I can see anything happen. Do you think replacing the Mitsubishi ra60h3847m1 PA module would potentially fix this radio or has more damage been done that I cannot properly diagnose or detect? I am having a hard time finding any information about testing PA modules and was hoping to find a way to test with a multi meter like you show in the video.
RF in, Gate voltage and Drain voltage all short to ground with high resistance while RF out does not short at all and the meter reads OL. Is that a sign that the finals have fail and are no longer letting RF through the PA module?
Any help or comments would be greatly appreciated.
The radio is a Connect Systems CS800D and my testing had been done on analog FM
I have a friend who checks his SWR off the radio and it is great. He is a ham operator and when he runs an amplifier it shows a much higher SWR. Should he be concerned or disregard the reading and only go by the. "barefoot" reading?
Yes, he should be concerned. When you are running a amplifier you need to place a SWR meter in two places, between the radio and amplifier and another between the amplifier and the antenna.
Ok. Thank you I'll tell him!
A message the Freightliner Cascadia is is impossible to get swrs much under two hope I don't smoke my little 29
They used to make an SWR meter with a built in Pi-L network (transmatch) you could install to regulate SWR. I use one to go from 10 meter to 11 meter on the same antenna.
Are you Excepting new customers
Do you figure it is exceeding the max voltage or the max current or both that blows those finals when SWR / RL is bad?
Would this cause it to melt? Not sure mine melted it was just an old Motorola cb burnt my hand too
Hi I need to know if you repair mark 3 browning
I am searching for HELP! I recently purchased a 10,11,12 meter President Lincoln II + I can not get SWRs lowered no matter what I do?????
Do you still work on radios?
I have a RK5640a running a Wilson 2000 on a 18 ft Wilson cable running for a few years w/0 SWR all the sudden it started crackling when receiving transmissions but I was able to transmit fine two days ago it just stopped receiving and transmitting all together thought cheap radio lasted longer than I expected however now I've installed two brand new radios both same issue seems when I go to calibrate it starts working normally and then the needle shoots back and forth a few times and then down to nothing no response the rx/tx lights up antenna lights off and no responses from the R/RF,SWR,CAL settings I'm puzzled could it be a bad antenna/cable killing these radios?
Yes it could. You may have a intermittent short. If the coax cable is routed through a door jamb the cable may have become crushed. Depending on what type of antenna you have I have seen loading coils fill up with water.
Hey Mike Bruce from Columbus can you get or is there available a frequency display for a ranger RCI 2960 FJP one leg is starting to flicker???