Appreciate the information. I will dig the scope out and have a look at all three voltage rails.
I have not had a chance to try the password yet. I totally agree that having a service manual will be necessary to most likely fix this thing properly. I at least have a Motorola 2600 service monitor to check the performance and calibration of the 1600S with. I have been looking for a service manual with no luck so far. Seems like 1600S information and support is pretty thin as compared to other models. Thanks, Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, DCFluX <dcf...@...> wrote: > > Dont know for sure on the 1600, but for future reference the > calibration password on the IFR-1900CSA is "CSMATE" which will have to > be input from the keypad with the shift engaged. Apparently it is > written in the service manual, which I don't have. With that said you > should probably stay out of there without a service manual and another > test set of known calibration. > > I'd suspect the caps getting weak in a negative voltage generator, > look for a ICL-7660 or MAX1044. Or I'd try replacing the audio > amplifier. > > On Thu, May 20, 2010 at 11:25 PM, burkleoj <joeburk...@...> wrote: > > My IFR 1600S is giving me a couple problems. > > > > One is it appears to have some high frequency noise in the received audio, > > but the generated signal and audio looks and sounds clean. I am thinking > > maybe some caps in the power supply might be causing this problem. > > > > I have the three inch thick operators manual, but does anyone have a > > service manual for one of these beasts. > > > > I tried to run the calibration from the aux menu but I can not seem to find > > a password that the operators manual makes reference of. > > > > Any help or ideas would be most appreciated. > > > > Thanks, > > Joe - WA7JAW > > > > I tried > > > > > > > > ------------------------------------ > > > > > > > > Yahoo! Groups Links > > > > > > > > >