5W-7W FM Transmitter module | How to assemble + Test

[@YourSelft487]

Do not forget to add thermal paste between 2SC1971 transistor and heat sink.

[@slender1357]

Ouais je le fesais sur les autres kits quand je l'utilisait à pleine puissance, mais la j'utilise que 300-500mW (pour ensuite l'amplifier à 15W) ducoup ça chauffe quasi pas

[@gamersungyoutube1468]

how do you change the input from the mic to line to sd card?

[@slender1357]

It's automatic. Put the sd card in, turn on the transmitter, and it will start playing the songs on the sd card. If you want to pause the music press the middle button on the screen pcb

[@pietrosalvato8654]

Hi, I see there are two jacks, one green and one pink. Are they the speaker/headphone and microphone inputs respectively? Thanks.

[@slender1357]

Yes but they often mix up the jack's colors...😅

[@planetgreen005]

What power source did you use? Can you attach a 12v car battery? If so, how?

[@slender1357]

@@planetgreen005 you can use a car battery, just put a diode and a ~3A fuse just in case. I used a lab bench power supply but you can use anything between like 10 to 14 volts.

Does this thing support RDS (or does the chip responsible for modulating the signal do, so that you could inject something there)?

[@slender1357]

Hi, the QN8066 IC which is used on this module has RDS capability but it isn't used. However someone managed to modify it and add RDS using a raspberry pi : github.com/ShadowLight8/Dynamic_RDS

[@smartelec]

Hello, do you know how to build a 1:1 current balun for this transmitter for a dipol antenna? I have problems with sheath waves. At the internet I only could find current baluns for 1-60 MHz.

[@slender1357]

As a homemade balun I just make a few turns of coax around 15cm near the dipole, it works. You can see me doing that on my video to make a dipole antenna

[@steveduecker9872]

For the power supply, is the on the connector positive or negative? Put another way, will my power supply need to be center positive or center negative?

[@slender1357]

Center is positive. There is no reverse polarity protection so it will burn if you wire it wrong. Be careful

[@steveduecker9872]

@@slender1357 Thanks!

[@igavik]

What's the unit of PO (Power Output, presumably) shown on the display of the transmitter? It displays 300 on max setting!

[@slender1357]

This value isn't really proportional to the power output level (i checked) 300 is the maximum level which is around 5 to 7 watts depending on the input voltage

[@igavik]

@@slender1357 Thank you for the prompt reply! So, I suppose, it just gives a rough idea about the power output, with 300 corresponding to ~5W-7W.

[@slender1357]

@@igavik yeah exactly

[@Airshootingpractice]

What’s the use of the memory slot??

[@Centar1964]

What is the SD card slot for?

[@slender1357]

You put mp3 files in there and it plays the songs from the sd card

[@boriskolev9513]

i bought one and buttons on display doesn't work, do you hace idea why is that?

[@slender1357]

@@boriskolev9513 press the middle button for 5 seconds or so Then push on the center button to select the setting you want to change Then use the top and bottom buttons to change the value Does it work?

[@sbmn7]

What is the approx range of this transmitter?

[@slender1357]

@@sbmn7 depends on antenna type, SWR, length of coax, frequency used, antenna height off ground etc... but it's more or less 5km

[@manon2899]

Incroyable

[@slender1357]

😑

[@andrzejtomaszewski5357]

Twoje lutowanie ...jak dziecko w szkole.

[@slender1357]

Not again 🤦‍♂️🤦‍♂️ tired of replying for 10hrs. Just read the similar comment i answered. Basically i had a tripod + 4kg camera in the way and even though the solder job isn't that great, you know for sure that it will work. Avoid comments like this unless you want to suggest something, your comment has 0 purpose. I lost 5 minutes of my life translating your comment too 😂😭

[@Krzysix.io11]

Your solder job is so bad

[@slender1357]

Thanks man, i do what i can when i have a 4kg camera with a tripod in the way Btw your solder job looks just as bad, if not worse as mine No need for shitty comments like yours, at least provide more info than that

[@Krzysix.io11]

@slender1357 wanna see my solder job? I can show you At least the transmitter worked after all Your soldering job looked bad cause you put the solder on the tip of soldering iron and then you touch soldering pad Try touching soldering pad with tip of iron first and then apply solder Or if you wanna solder like you soldered on the vid, consider buying liquid flux or make one from 99% isopropyl alcohol and rosin EDIT: i forgot about one thing: Your soldering iron tip was dirty af Clean it while it's hot using piece of wet toilet paper, or if the tar doesn't want to come of easily detach tip from rest of soldering iron and clean it using steal wool or baking soda on wet sponge. You could leave it overnight in isopropyl alcohol but I never tested that so I'm not sure if it'll work

[@slender1357]

@@Krzysix.io11 @PiroZiomek @PiroZiomek @PiroZiomek bro if i used the tip it's because i had a big ass camera and a tripod in the way, i never use the tip, i had to wrap my arm around the camera to be able to solder. I've been soldering for nearly 10 years, i know how to do it. I know how to clean the iron, how to make a good loking solder job etc.. but when i don't have time/tools/etc i don't care if it looks like crap honestly. If it works it works and you know for sure that a shitty solder job will work fine as long as the connection is made, nothing is shorting out and you haven't got 10kg of solder on a single pad. Especially on this crappy transmitter pcb where you have only THT components to solder. That's why i didn't bother to clean the iron. If it was SMD i would have cleaned it at least, otherwise it would have made a mess. And the unit works perfectly btw. Getting 5W at 12V, the wattmeter on the video showing half the power wasnt made for this band, when i don't have the tools,i manage to make it work somehow lol. Now i have a proper rf wattmeter that supports the FM band and i can tell you that everything works fine. not 7W like they claim, you would need ~13V to get the 7W, because they limit the driver stage 2sc4767's collector voltage to 10-11V for some reason. Must be to prevent distortion or oscillation of the transistor) I'm using this module right now on a pirate 80-100W TX as driver(and there's no issues with this transmitter module's harmonics unlike what people seem to say because it's got a 7-order butterworth low pass filter on the output, people on the internet seem to hate this module for some reason) Have a nice day