Re: [Repeater-Builder] Help with Wacom WP-639 Duplexer

[Kevin Custer]

m1ror wrote: Hello All This is my second posting but I'm not sure if my first attempt made it to the list. I bought a set of what appear to be good condition Wacom WP-639 (144- 174Mhz) Duplexers originally tuned for 156Mhz. A friend has attempted to align the filters but is having problem aligning the notch down to 145Mhz. The problem he tells me is he can only get the notch down to 148Mhz with the Invar rods pushed all the way in. He has made up new patching loom and still the same result. Has any body played with these and could offer any advice? Have him swap the ports and try again, in other words, tune the duplexer backwards from the way it is presently tuned using the opposite sides for the receiver and transmitter.  Minimum frequency separation happens with the rods all the way in, which leads me to believe he is attempting to tune the duplexer upside down, on the 'wrong' notch; there are two notches, as explained below.... This article explains the basic principal for the Wacom WP-641 and 639 style pass notch network.  While specifically written about the 641, the effects are the same for the 639, however, the notch depth won't be as deep with the 639 as what is stated in the article: <http://www.repeater-builder.com/wacom/wacombpbrnotes.html> Complete tuning directions are available from this page: <http://www.repeater-builder.com/wacom/wp6xxVHFtuninginstructions.pdf> If you still encounter difficulty after attempting the switch-a-roo, email us back.... Kevin 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 the Yahoo! Terms of Service.