Re: [Repeater-Builder] Re: Band Pass Duplexer Tuning

On 2/22/07, fxbuilder <[EMAIL PROTECTED]> wrote: > I didn't have a load on the 3rd port when I tuned it. I only have 1 > dummy load. I can add an antenna to the 3rd port though I know that > would less than ideal but better than nothing I suppose. I have found > some schematics for the pads and

RE: [Repeater-Builder] Re: Band Pass Duplexer Tuning

Like Ken said; all 3 ports need to be terminated in 50 ohms when tuning. A signal generator is usually fairly close to 50 ohms, a receiver may or may not be, usually not. The unused port at the time needs a 50 ohm load. The best way is to use a 6 db pad on gen and rec sides while tuning. But wh

Re: [Repeater-Builder] Re: Band Pass Duplexer Tuning

At 06:49 AM 2/20/2007, you wrote: >Ok... So I've tuned this duplexer as a notch device. Put a 2 watt >handheld into a dummy load and watt meter (not in that order mind you) >and it seems to reject the corresponding frequencies. My question now >is... Why did my swr jump from 1:1.3 to 1:3. Do I nee

RE: [Repeater-Builder] Re: Band Pass Duplexer Tuning

Lots of the small mobile duplexers (notch type) have fixed capacitors inside and you can only adjust the cavity tuning, which tunes the notch. This type duplexer is limited in how far from the design frequency you can tune it as the capacitors are fixed. The cavities will tune but the loss goes.

Re: [Repeater-Builder] Re: Band Pass Duplexer Tuning

At 02:09 PM 2/16/2007, you wrote: >I emailed the place I bought it from and that is what I was told. >Band Pass. No caps on it for notch tuning as on celwave. Am I missing >something here? <---As Skipp pointed out, most the so-called "mobile duplexers" are notch only. You have a make and model #

Re: [Repeater-Builder] Re: Band Pass Duplexer Tuning

At 02:14 PM 2/16/2007, you wrote: Yes, this is a flat pack. The place I bought it from told me it was a band pass. Thanks Scott, I'll try your method. Craig