Topband: Passive Receive Antenna Splitter
Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
I've used a video selector box (for 75 ohm RF, with F connectors) that Radio Shack used to sell. It was a 4-in 2-out matrix, and allowed either of two radios to have any of the 4 available antennas. It also allowed two radios to share an antenna simultaneously. I doubt R/S still sells it, but there might be something available from MCM or the like. Kirk K4RO On 3/13/2014 8:13 PM, Gary K9GS wrote: Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
That should work fine, Gary! You would have around 3 dB loss in a two-way splitter + a SMALL amount of mismatch-loss for the 50-75 ohm mismatch. I would expect that if your radio will work with the beverage signal, you won't likely need the preamp to make up for tha very modest loss from the splitter and the 75-50 ohm mismatch! Should work fine! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Gary K9GS Sent: Thursday, March 13, 2014 9:14 PM To: Topband Mailing List Subject: Topband: Passive Receive Antenna Splitter Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
One word of caution, Gary, if the CATV splitter is a transformer type, rather than resistive it may of have enough low-frequency response for 160 m! Check around with RS and your local electronics stores for 50 ohm 2-way splitters. Those are generally resistive and have frequency response from DC up to a GHz or so. Some of the TV stuff is transformer coupled. 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Gary K9GS Sent: Thursday, March 13, 2014 9:14 PM To: Topband Mailing List Subject: Topband: Passive Receive Antenna Splitter Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
I use a couple of old CATV splitters for general purposes around here and can't measure any excess (more than 3 - 4 dB) loss from common to either port. If you want a known good design to build some of your own, try: http://cliftonlaboratories.com/z10050a_3_db_hybrid.htm 73, ... Joe, W4TV On 3/13/2014 9:13 PM, Gary K9GS wrote: Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
You might find this of interest, the magic-t combiner/splitter: http://www.w8ji.com/combiner_and_splitters.htm 73, Charlie, N0TT On Thu, 13 Mar 2014 20:13:44 -0500 Gary K9GS garyk...@wi.rr.com writes: Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
Hi Gary, The most efficient way to share a Beverage among two (or as many as four) bands to use W3LPL bandpass filters. Loss of each filter is in the order of 1.5 dB vs. about 3.5 dB for a typical Magic-T combiner/splitter. http://www.k1ttt.net/technote/w3lplfil.html Just connect the inputs of both filters to the Beverage antenna and the output of each filter to each radio. The reason this works so well is that the impedance of the filters is very high outside their pass bands. I have dozens of these filters in my station; they're inexpensive, very effective and easy to build. 73 Frank W3LPL - Original Message - From: Gary K9GS garyk...@wi.rr.com To: Topband Mailing List topband@contesting.com Sent: Friday, March 14, 2014 1:13:44 AM Subject: Topband: Passive Receive Antenna Splitter Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
Hi This may be of interest http://www.dxing.info/equipment/rolling_your_own_bryant.dx 73 Tony VK2IC On Fri, Mar 14, 2014 at 12:13 PM, Gary K9GS garyk...@wi.rr.com wrote: Can anyone point me to a design for a splitter for sharing a Beverage antenna between two receivers? This is for Field Day so these are not optimized Beverages by any means. Just want to allow the 80/40M stations to share antennas. Nothing fancy. My thoughts are to just use a CATV 2-Way splitter at the output of the Beverage matching transformer and run separate feed-lines to each radio. I'm pretty sure these things work down to 1 MHz but have not measured them. I can use the pre-amp in the radio (K3) to compensate for the loss. Thoughts? -- 73, Gary K9GS Greater Milwaukee DX Association: http://www.gmdxa.org Society of Midwest Contesters: http://www.w9smc.com CW Ops #1032 http://www.cwops.org _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
