The JRL21 Noise Reduction Module removes fan noise much better than expected. (Or perhaps my expectations were too low.) You can listen to two ‘before/after/before‘ audio examples. See links at the end of the article. Prostorija oko radio-uređaja ume biti vrlo bučna, posebno ako su tu veliki pojačavači snage i njihovi ventilatori. Može biti poželjno…
NanoVNA jeste open-source vektorski mrežni analizator – sprava za merenje radnih parametara antena i svega drugog u šta ulaze i kroz šta prolaze signali visokih frekvencija. Minijaturan je i relativno jeftin, dostupan prosečnom radio-amateru koji sam petlja oko antena, filtera, pojačavača. Pomoću NanoVNA može se meriti i analizirati impedansa, odnos stojećih talasa (SWR), meriti frekvencija…
If you follow groups or forums where hams ask for help with equipment issues, you may have noticed that transmitters show a pronounced tendency to fail while they are being used for digital (data) modes. It seems that people often forget that amateur transceivers are not designed to transmit at full power for longer periods…
Lepo radi i veoma mi je koristan prethodni projekt instrumenta koji govori, solidno dorađen:https://yu2zz.com/2020/06/17/instrument-koji-govori-talking-multimeter-v2-0/ Ovo sada jeste tek zanimljiv eksperiment s novim instrumentom i sa SCPI protokolom koji je danas skoro pa univerzalno podržan kod kvalitetnijih mernih instrumenata i drugih laboratorijskih uređaja: osciloskopa, analizatora spektra, izvora napajanja itd. Zavisno od modela, fizički interfejs može biti…
There are countless projects for measuring devices based on Arduino, often using quite basic measurement sensors and circuits. Still, we can improve accuracy with a one-time calibration against a reference device at a few (or more) points, implementing the simplest linear interpolation/mapping/correcting function, just a few lines of code. Please see the first picture. It’s…
ArduinoDroid is an Arduino IDE for Android. The paid version offers some advanced options, but all that really matters to most people is already there in the free version: you can write, open, edit, save, compile and upload programs to Arduino boards, use the Serial Monitor and all the usual options. To connect the phone…
The FTDI drivers are easily available and often already present in the OS. The interface will present itself to the user as a new COM port. In Device Manager go to this new COM port Properties->Port Settings->Advanced. Then in the Miscellaneous Options section (bottom right) uncheck Serial Enumerator and check Disable Modem Ctrl at Startup.…
Pločicu preko Aliekspresa prodaje firma Wavgat. U pitanju je preimenovan GSM modul SIM800C. Pločica se napaja s 5 V, a takođe ima konvertore nivoa, tako da s njom može neposredno komunicirati mikrokontroler koji radi na 5 V. To je pogodno, recimo, za eksperimente s Arduinom. Modul podržava glasovne pozive, SMS, GPRS, USSD. S njim se…
Radio-amateri mogu voditi duge razgovore o mikrofonima i SSB modulaciji, kao ovde:https://www.eham.net/article/8069 Iskustvo sa kratkih talasa: ako se sve ostalo podesi kako treba, elektretska (“kondenzatorska”) kapsula od 50 dinara može zvučati odlično. To je ona, na primer, sa slušalica s mikrofonom za PC ili: https://www.mgelectronic.rs/mikrofonska-kapsula U prolazu kroz SSB predajnik i prijemnik, audio-signalu ograničeni su…