In spite of trying all of the suggestions offered her, my radios still freeze after about 1 1/2 hrs flight. I've deleted all my saved PMDG flights and completely uninstalled and reinstalled and still the radios freeze. I've made sure that the avionics switch on the default cessna is on before I select the 737 and the voltages on the overhead all look fine throughout my flights. After I land, if I shut down all of the electrics and restart , the radios are unfrozen. I think this may only have started after I downloaded FSUIPC version 3.48 - could this be the problem. Can I use an earlier (registered - free with Captain Speaking 2002) version of FSUIPC to see if that does the trick ? Could also someone tell me exactly how the overhead electric switches should be set after the engines are runing please, as most tutorials don't really make it clear. I tend to set Gen 1 on the rh switch and tr1 on the lh. Gen buses li. Also should the APU be on or not as I've rad different ideas on this .

Dave,Sounds like your GEN are not setup properly. I am trying to understand your sentences "I tend to set Gen 1 on the rh switch and tr1 on the lh. Gen buses li.". I suspect you are talking about the two rotary knobs in your first sentence. These knobs has nothing to do with your electrical distribution. They are only for you to select what the electrical display will show. For your screen shot below you should set the LH knob on BAT. The second sentence escapes me unfortunately.Make sure you have BAT ON, STBY PWR ON, GEN 1 ON and GEN 2 ON. No blue lights on the overhead. APU should be off if you have OP GENs. Maybe you could attach a screenshot of your overhead?Also. Make sure you are using the latest versions of the NG. Version 1.3 for the 600/700 and 1.1 for the 800/900. I do remember we had some problems with the radios in one earlier version.FSUIPC should not be a culprit here but if you have installed PSS products lately you could try to move or rename the FSUIPC.KEY file from the modules folder to see if that fixes things. But the PSS bug will usually make your DUs black.To me it sounds like a voltage problem. The radios are the first equipment to go when the voltage drops below 22 Volts.Hope it helps,

Thanks again. In my second sentence I was trying to explain that I always start the flight by laoding the default Cessna, switching everything off and then loading the 737/600/700. On one or teo of my saved flights I had turned the avionics switch off on the cessna as well as the master switch and the start up key - I thought this was causing the problem but doen't look like it is. I'll try the overhead a syou suggest over the weekend and I might try a flight without starting it from cold and dark to see if the default settings react any different.This is particularly irritating because this problem seems to have started very suddenly - I'd previously carried out many flights without problems - that's what made me think it was loading a later version of FSUIPC what did it. Many thanks anyway and i'll try to get a sceenshot of the overhead when it happens. Pretty sure I'm version 1.3.

I have this problem with the gauges. Sometimes they work and sometimes they don't. Just switching VC and 3D cocpits can cause either condition.I believe the problem is with FSUIPC; since with the release of the FS9 update, FSUIPC was changed; then again it could be the FS9 update.

Waldo and Dave,Like Matts I will bet my last USD that it is NOT a problem with FSUIPC 3.48. I am on a beta test team with Pete Dowson, and pretty much know what changes etc in his versions and that would have nothing to do with the NG.What I may suspect are two things; first are all your PMDG version installed in the correct order and are they current as the poster above said. I re-installed and put one update incorrectly into the 800/900 and the plane would not fly correctly with lots of problem. The second point, have you tried to start FS with the NG as the default start plane. I always save my FS flights with the NG, and then start FS from the last saved spot, with this setup I have never had the radio or other electrical problems that many have reported.I hope this helps.Bob JohnsonDenver

Mats,Problem solved - you were dead right !! I had switched off the generator bus and had two bright blue lights still on. I mistaken the role of the rotary knobs and now I set the right hand switch to 'Gen 1' and the left hand to 'stnby pwr' All now works fine thank you. Did two successful ILS landings at Malta (LMML) and Palma (LEPA) with no problems,Many thanks again.