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

2007-02-22 Thread Nate Duehr
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 will

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

2007-02-20 Thread Ken Arck
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 need

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

2007-02-20 Thread Gary Schafer
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

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

2007-02-16 Thread Ken Arck
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 Don't! Scott is talking about a notch type duplexer, not a pass band one. Ken --- In

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

2007-02-16 Thread Ken Arck
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

2007-02-16 Thread Gary Schafer
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.