While trying to align a MASTRII , I discovered that my IFR1500 OCXO lost the oven. (or so it seems). Prior to this, I noticed that the frequency was 170Hz off and it could not be netted with the front control. Then, I found it 10Khz off frequency at 450Mhz. Watching the frequency of the 10MHZ oscillator from cold start to 10 minutes warm-up time, I never see the frequency change. This seems to be telling me that the oven has failed in the Oven Controller Crystal Oscillator. (This IFR1500 has Opt 02 installed).
I made a call to Auburn Electronics Labs and spoke to William. He was very informative, but gave me an estimate of $1,800 to replace the oven or about $1,000 to retrofit it with a more modern frequency standard. My third option is to always use an external 10Mhz reference source, but the IFR1500 needs 1 to 1.5 volts of signal to switch from the internal to external reference source. A fourth option would be to try to fix the existing oven by repairing or replacing the nichrome wire that probably burned open. I did catch a whiff of something burning near my workbench but never identified what it was, probably was the nichrome wire burning open. Anyone have experience with this kind of problem? Any suggestions? 73, Joe, K1ike > _._,___
