I own several sets of Wacom 641's, so I'll correct Eric's figures. The Wacom 641 is a 4 cavity BpBr duplexer using 8 inch cans.
Eric Lemmon wrote: >A 2m repeater on 147.090/147.690, with a 50 watt transmitter and a 0.35 uV >receiver generally requires about 88 dB of isolation for no desense. The >WP-641 duplexer is rated at 85 dB, > While the WP-641 is rated at 85 dB, that spec is at the highband literature standard of 500 kiloHertz separation, not 600 kc as referenced above, when used on a 2 meter repeater. >but most can manage only 80-83 dB. > Incorrect, Wacom specified the WP-641 at 90 dB isolation at 600 kc, but they will actually manage 93 dB with careful tuning. 93 dB will allow a 100 watt 2 meter repeater to properly work using a .35 uV (-116 dBm) receiver. A *good* repeater like a Micor or Mastr II (read less than typical transmitter side band noise) will allow a 100 watt repeater operate properly with a factory preamp (-125 dBm) receiver. Granted, this is its limit, but that isn't too bad considering. A Tube Type amplifier (GE 4EF5A1) or PLL exciter and solid state PA will allow about 250 watts to be duplexed using the Wacom WP-641. These specifications can be backed up from the factory literature available here: http://www.repeater-builder.com/pdf/wp641.pdf Maybe Eric was thinking of the WP-639 duplexer that uses 4, 5 inch cans? His figures would be much closer.... Kevin Custer 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/
