Bob, I've seen on spectrum anal spur problems with radio shops turning up the power on GE Mastr IIs and get lots of unwanted spurs out of the PAs. This was done of course as to impress the customer with a watt meter.
It also may not happen on the bench for a short time, but with use it can get worse. I've seen it in other PAs, some linear or were linear when operated correctly. I would say in most cases it was with the earlier versions. 73, ron, n9ee/r >From: [EMAIL PROTECTED] >Date: 2008/03/13 Thu AM 10:36:28 CDT >To: [email protected] >Subject: Re: [Repeater-Builder] Master II 110w repeater > >At 3/13/2008 06:35, you wrote: > >>Many GE Mastr II PAs will put out 150 watt. However, where all this power >>is in freq is often not at the freq one wants...it is in spurs. Looks good >>on watt meter, but not on spectrum anal. > >I have never seen this on a Mastr II PA unless it was defective (bad >transistor, filter cap, etc.). Many G.E. RFPAs will output well in excess >of their rating, & do so cleanly. I have a "25 watt" VHFHB MVP that will >do over 50 watts. The real reason you don't want to do this is that the >PCB & chassis design will not handle the dissipated power for very long, >resulting in heat-related failures such as you describe. > >>You do need to get the power output down to spec for spectral reasons > >No. > >> and also for life of the PA. > >Yes. > >Bob NO6B > > Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
