.....ispravljač je podešen na 48 volti po uputstvu turbodisela i on je ok....sa naponom.....te u nedelju naveče smo sve povezali ...stavili bird opterećenje za antenu i uporabili FT 817 za pobudu..abaut oko 400-500 mW i na watmetru je pokazalo oko 50 Wati....i onda sve zaribalo.....stvar je vukla oko 20 Ampera ..i više te je
Nazalost dogodilo se sto je!
Tesko je iskopati tocno o kom modelu PA se radi jer po slici ovaj je iz 2005, druga serija je iz 2007 i pise da je upotrijebljen MOSFET SD2942. Ono sto je za sve zajednicko je procedura testiranja i pustanja u pogon.
PROTOCOL TEST
PRELIMINARIES
1) Put conductive paste on 350MOD144 and screw it on dissipator
2) Close 8 screws 3MA
3) Connected IN and OUT of module to RF connectors
4) Connected tester on Ampere
5) Connected OUT RF connector to good wattmeter
6) Connected dummy load 50 Ω
7) Conneted Spectrum Analyzer
8 Adjust power supply limitator to 400 - 500 mA @ 49 Volt
We advice connected low pass filter with low insertion loss (0,15 dB or better) with -40 dB UP 175 MHz.
1) Connected generetor to RF INPUT connector
2) Switch ON power supply adjusted on 49 Volt and limitated on 600 mA
3) Check “BIAS current” ABOUT 400 - 500 mA, adjust it with R2 if necessary.
After all operation remove limitator on current and switch on generator (TX); adjust input to 1 W, check RF OUT and increase step by step until to obtain RF 350 Watt.
We recommended don’t exeeted power out, however don’t exeeted 11 – 12 A.
You can use 50 Volt, in this case the performance will be little bit better, but we recommended to use the module on 350.
We recommended to use a good blower on the dissipator, to have on the Fet no more than 45° C.
The Fet must be protected from R.O.S., we advice to make PCBord to obtain 5 negative Volt to connected on PIN “INHIBIT”; we advice a threshold of –10 dB @ 350 Watt out