> -----Original Message----- > From: [email protected] [mailto:Repeater- > [EMAIL PROTECTED] On Behalf Of skipp025 > Sent: Friday, March 02, 2007 7:51 PM > To: [email protected] > Subject: [Repeater-Builder] Re: repeater problems, duplexer etc. > > > > There is no way you can tune a duplexer with a power meter > > or swr meter. They are not sensitive enough to see the low > > level signals even if your signal source is a good size > > transmitter. > > Sure you can... just depends on the duplexer, test equipment and > what realistic type of results you expect when the smoke clears. > > On a cold wet mountain top any port in the storm works if you > have to go that way. > > You'd be surprised how close you can approximate when you have > to. > > cheers, > s. >
Using a wattmeter on a pass band type cavity, yes! Trying to tune a notch duplexer with a wattmeter you do nothing but shoot yourself in the foot. If you have a duplexer with only 50 db of notch depth and even a 100 watt transmitter, 50 db down leaves you with 1 mill watt of power. You are not going to see that on any wattmeter unless you happen to have a mill watt slug. But that isn't enough sensitivity to tune a decent duplexer with. The poster as I understand was trying to do it with a 5 watt HT. Now you are down to less than a tenth of a mill watt at 50 db. Playing with the tuning on the duplexer for minimum desense on the receiver at the "remote" site in a pinch can sometimes be done but you have to be in the ball park in the first place. 73 Gary K4FMX
