[BC] Platinum-Z problem

[Lotus Engineering]

Allen,
	Last Month I spent three days with a Harris field tech replacing the filter boards that go on the surface that isolates the RF sections from the  control sections in a Z20 (combined Z10's) that had a roof leak into it.  These filter cards (About $100 each) are relatively easy to replace. They go between the ribbon cables above the shelf and the ribbon cables below the shelf.  They could cause intermittent problems based on the power level if they stopped filtering.  They were causing our diagnostics to be very strange and eventually intermittent shutdowns became a transmitter hard off. I had to call in the field rep because nothing I saw in the diagnostics was making sense. 
 
	There are two sizes depending on cable, 20 or 26 pin.  If you are lucky it will be just one or a few.  Our remote Mt. top box took over 20 of the 40 between the two halves.  Ice hitting the roof on Mt. Potosi caused the leak and by the time it started giving problems, the site was almost inaccessible and the damage had been done.  Drop me a note off list and I'll send you some pictures of what they looked like. (billc at lvradio.com)

	They have a thin sheet plastic cover that may mask the problem, but when that is removed the corrosion became obvious.  Most of them are pretty easy to get to. 

	The leak caused some other problems as well with a master controller card and an IP back plane.  Those were pretty easy to replace once I knew what to replace.

Bill

Bill Croghan CPBE WBØKSW
Chief Engineer, 
KOMP/KXPT/KENO/KBAD/KWWN/KWID
Lotus Broadcasting, Las Vegas, NV
Direct   702-315-3030
Cell	702-400-2558

> -----Original Message-----
>  [mailto:broadcast-
> bounces at radiolists.net] From: Allen Sherrill
> 
> Hey folks:
> 
> 
> 
> We are getting ready to help out one of the local non-coms with an
> intermittent foldback or muting problem on a Harris Platinum-Z10
> (analog, no HD).  Several times a day the exciter is apparently muting.
> The fault indications seem to be VSWR trips.  The problem occurs at any
> power level above about a kilowatt.  Station frequency is 88.1.
> 
> >>>>>snip<<<<<<