Thanks Rick, Duplexer is a RFS 6MC 450s and the Antenna is an RFI CD4 vertical dipole,
http://www.rfi.com.au/downloads/wireless/RFI-antenna-catalogue.pdf With the antenna connected directly to the radio via a length of RG58 i am reading a vswr of about 1.3 at 35 watts output from the Tx radio. Because of the problems with restrictions on Antenna positions and the path that the cable has to run i doubt that i would be able to run hardline or its alternative, ( several sharp 90 Degree bends ) I am not particularly concerned with how much loss i am going to get with the duplexer as it is for local coverage only but was just interested in whether i might be able to run the Tx radio on low power ( 10 Watts ) to prolong its life and reduce the heat that it produces at full power. Thanks again for your reply, Regards.- -- In [email protected], Rick Szajkowski <va3r...@...> wrote: > > 1 > cant answer to the info on your duplexer, you have not given any info on the > make model > > you need to tune your duplexer to the pair you are useing .. > > 2 you should have a 1.1 match from the duplxer and the radio ( if the > duplexer is tuned right) > and a 1.1 match from the duplexer to the ant if the ant is tuned right .. > if you have a miss match on your ant it will play nasty things with your > radios (repeater) > > 3 > again we need more info on the duplexer as to loss .. and your cable from > the duplexer to ant . and what type of ant ? > does it have any gain to make up for some losses .. also depends how much > power you are useing .. > > If I remember right I have a loss of around 1.5 db in the duplxer I run > 7/8 hard line about 50ft and a 210 c4 ant and run around 60w out of the > repeater > > I hope this helps > > > On Sat, Apr 4, 2009 at 10:12 AM, tait700 <cscan...@...> wrote: > > > Hello, > > I am new to Repeater Building and was wondering if someone Knowledgeable > > would be able to answer Three Questions for me ? > > > > 1, With a Duplexer tuned to say 467.00 Low side and 477.00 high side will > > the duplexer only function at those Frequencies, i.e if the system has > > another pair of Tx / Rx frequencies that are close to the tuned pair is the > > duplexer able to handle both sets or only the ones that is is specially > > tuned for ? > > > > 2. When the system is completed and the final vswr readings are being taken > > is the vswr meter inserted between the Duplexer and the Antenna or between > > the Duplexer and the Tx radio ? I understand that when checking the vswr on > > a normal conventional radio / antenna system the reading is taken on both > > the highest and lowest Tx frequency, and any adjustments made to give the > > best result at the centre of the two. > > Is the procedure the same for a duplexer with the checking frequency being > > the midle of the Tx / Rx seperation ? > > > > 3. Could someone possibly indicate how much signal loss i could reasonably > > expect with the insertion of the Duplexer to the system. > > I have a very short cable run from the Duplexer to the single antenna < 5M > > and am running RG58U/C. > > I realize i should be running Hardline to minimize signal loss but we have > > very strict building codes here which prohibit any type extended vertical > > antennas and i have had to conceal its location requiring a convoluted path > > for the feedline to the antenna. > > > > Sorry for the longwinded post, i would be very grateful for any and all > > info people could provide on the above. > > > > Thank you for your help, > > > > Regards, > > > > Tait 700 > > > > > > >
