Thanks for the leads. The Cushman does indeed have the tracking generator and spectrum analyzer. The article you sent me is far more understanding than what I have gotten in the past. I know what duplexers do, just really learning the difference between Bp Reject, Bandpass, do they get tuned one at a time, then coupled together and tuned as a whole, and this information is very helpful. Thanks again.
Mathew ----- Original Message ----- From: "Eric Lemmon" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, January 01, 2005 4:05 PM Subject: Re: [Repeater-Builder] Need Literature on tuning Duplexers > > Mathew, > > Just as there are many different designs of duplexers, so there are > different methods of tuning them. The best source for tuning a > particular duplexer is the manufacturer of that unit. > > I am not familiar with the Cushman CE-6030 service monitor, so I don't > know how suitable it is for tuning duplexers. As a minimum, the service > monitor or spectrum analyzer should be very accurate and it must have a > tracking generator. Many spectrum analyzers are of only modest > accuracy; it is difficult to tune a 2m duplexer to a 600 kHz split, when > the analyzer's frequency setting cannot be known any better than 100 > kHz. Most service monitors are much more accurate than a spectrum > analyzer. > > A return-loss bridge is a valuable accessory for tuning the bandpass of > a cavity, and for balancing the input and output loops. An RLB is an > inherent feature of a network analyzer, and that is why most duplexer > manufacturers use them on the production line and recommend their use > for field retuning. While it is true that almost any duplexer can be > roughly tuned to perhaps 95% of its optimum tuning with very crude > instruments- a handheld radio and an RSSI meter, for example- that last > 5% is usually attainable only with a network analyzer. Some repeater > owners feel that extra 5% is important, and some don't. > > EMR Corporation has a very informative Application Note on duplexer > tuning here: > > <http://www.emrcorp.com/images/tech_papers/tech_cover/antenna_duplexors(15-2 6).pdf> > > 73, Eric Lemmon WB6FLY > > w9mwq wrote: > > > > Anyone know any good books that will teach me how to go about tuning > > duplexers. I've downloaded several articles, but need something > > that goes in depth. Or if anyone is willing to work with me, it > > would be appreciated. I have a Cushman CE-6030 SM to work with > > here. Thanks! > > > > Mathew > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
