Ken, You're right about this problem being a stumper! It seems as if you have checked all the obvious things, and still, it does not work. Has this duplexer worked before? If you don't know from personal experience that it was working properly before it came into your hands, perhaps the prior owner damaged it by trying to tune it while transmitting through it, or Mother Nature might have given it the lightning hi-pot test.
If you have a copy of the Motorola manual 6881102E96 covering the T1500A series of cavity filters and duplexers, you might check that the correct loops are installed in the suspect cavity, and that they are identical to the ones in the matching cavity that is okay. If you don't have this valuable manual, it is still in print and available from Motorola Parts for less than $12. I have tuned many of this model duplexer, and I know that it is very simple and has few parts. Since you have covered the obvious, there's not much left besides internal damage or an incorrect or faulty loop. 73, Eric Lemmon WB6FLY Ken Arck wrote: > > Hmmm, here's a kicker.... > > At 3 megs above the pass frequency, I can adjust for a sharp, deep null > about centered in the slot. At 4 megs above, it starts to get noticeably > wider and almost to the outside edge of the slot. And of course we know > what 5 megs produces. > > Curiouser and curiouser... > > Ken > ------------------------------------------------------------------------------ > President and CTO - Arcom Communications > Makers of state-of-the-art repeater controllers and accessories. > http://www.ah6le.net/arcom/index.html > Be sure to see our products at this year's Dayton Hamvention! > Repeater Builders spaces 707 through 710 > AH6LE/R - IRLP Node 3000 > http://www.irlp.net > > > 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/
