[TowerTalk] Looking for a HP 80/40 Duplexer

[Jack Brindle]

Two feed lines on one antenna is definitely not a solution. The only isolation would be whatever loss is in the feed lines. Basically you would be putting high power directly into the *other* receiver. I doubt that is survivable.

Pavel has a page that specifically discusses his 80/40 diplexer. It is definitely worth a look. That is at: https://va6am.com/2017/01/01/4080-band-diplexer/

73,
Jack, W6FB


> On Nov 17, 2025, at 10:04 PM, john at kk9a.com wrote:
> 
> As others have stated I am sure that VA6AM can make a 80/40 duplexer for you
> however the easiest approach would be to just run another feedline to your
> fan dipole.
> 
> John KK9A
> 
> 
> Randy Farmer w8fn wrote:
> 
> I'm investigating upgrading my station from its present 500W capability 
> to 1500W. I've located sources for most of the up-rated bandpass filters 
> and other hardware required for the project, but can't seem to find a 
> source for a duplexer to split a 80-40 dipole for SO2R use. I'm 
> presently using one of the Low Band Systems 500W 80/40/20 triplexers for 
> this function. LBS apparently makes a 1500W 80/40 duplexer, but it 
> appears the LBS stuff is no longer available in the USA. Does anyone 
> have or know of a suitable 1500W unit? I do NOT need it to be rated for 
> 100% duty cycle since I'm only interested in CW and occasional SSB use, 
> but it needs to hold up under contest conditions with a full power 
> amplifier.
> 
> 4O3A makes a nice 20/15/10 triplexer, but they don't have any high power 
> 80/40 units. Antennas-Amplifiers (distributed by DX Engineering) makes 
> nice HP bandpass filters, but not a triplexer or duplexer. VA6AM (also 
> distributed by DX Engineering) doesn't have any high power devices.
> 
> 73...
> Randy, W8FN
> 
> 
> _______________________________________________
> 
> 
> 
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk