Re: Topband: Passive Receive Antenna Splitter
People also have to be careful with systems. The resistor on center tap splits the signal, but runs the ports out-of-phase. This is OK when you need a 180 flip between port, or you don't care about phase, but it can get you in trouble in many cases. Also, the very same thing that makes it good wideband system, tight coupling between the common and load windings, also tends to make the splitter misbehave at higher frequencies. This is what the one transformer splitter never became real popular in extremely wide bandwidth systems. - Original Message - From: Pete Smith N4ZR n...@contesting.com To: topband@contesting.com Sent: Saturday, March 15, 2014 5:44 PM Subject: Re: Topband: Passive Receive Antenna Splitter Typically the CATV splitters are marked 5-1000 MHz or similar. I've often wondered how much rolloff there was beyond the basic 3-4 dB down at topband. I have a Clifton that I built myself, but have not been able to achieve the insertion loss and isolation specs - which may well be my fault. 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 3/13/2014 11:07 PM, Joe Subich, W4TV wrote: 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 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3722/7200 - Release Date: 03/15/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
Have a look on ebay - rx splitter . http://www.ebay.com/itm/ANTENNA-SPLITTER-COMBINER-RX-HF-1-50-MHz-SO-239-conn ectors-/321217220222?pt=US_Radio_Comm_Antennashash=item4aca09ce7e 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
Im in the wrong business! Carl KM1H Have a look on ebay - rx splitter . http://www.ebay.com/itm/ANTENNA-SPLITTER-COMBINER-RX-HF-1-50-MHz-SO-239-conn ectors-/321217220222?pt=US_Radio_Comm_Antennashash=item4aca09ce7e 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 - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4336 / Virus Database: 3722/7201 - Release Date: 03/16/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
I use this http://f6aoj.ao-journal.com/crbst_136.html From: k...@jeremy.mv.com To: kajo...@gmail.com; topband@contesting.com Date: Sun, 16 Mar 2014 13:54:44 -0400 Subject: Re: Topband: Passive Receive Antenna Splitter Im in the wrong business! Carl KM1H Have a look on ebay - rx splitter . http://www.ebay.com/itm/ANTENNA-SPLITTER-COMBINER-RX-HF-1-50-MHz-SO-239-conn ectors-/321217220222?pt=US_Radio_Comm_Antennashash=item4aca09ce7e 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 - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4336 / Virus Database: 3722/7201 - Release Date: 03/16/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
Typically the CATV splitters are marked 5-1000 MHz or similar. I've often wondered how much rolloff there was beyond the basic 3-4 dB down at topband. I have a Clifton that I built myself, but have not been able to achieve the insertion loss and isolation specs - which may well be my fault. 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 3/13/2014 11:07 PM, Joe Subich, W4TV wrote: 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 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
All the TV splitters Ive taken apart are pure autotransformers with poor isolation. A VNA will show them deterioating and doing very little at 160M. It is simple enough to wind transformers for a splitter using 1/2 type 43 toroids. See this link that gives an excellent discussion and also shows the cheap way of doing it and the better way. Guess what is used in consumer grade CATV versions. http://www.minicircuits.com/app/AN10-006.pdf Both versions have been in handbooks for decades and I first started using them with Beverages in the mid 80's. Ive also used them as combiners and connecting various combinations of 2 Beverages with some very beneficial performance at times. Port to port isolation was very important to me. There are also several other on line versions, good and bad, if you do a Goggle for how to make a 2 way 50 ohm splitter Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: garyk...@wi.rr.com; 'Topband Mailing List' topband@contesting.com Sent: Thursday, March 13, 2014 9:41 PM Subject: 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 - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4336 / Virus Database: 3722/7192 - Release Date: 03/13/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Passive Receive Antenna Splitter
Yeah, that's why I cautioned Gary about using CATV splitters at 160m. Seems that he has enough reserve gain with his Beverage and K3, that he could certainly tolerate the loss of a 50 ohm resistive splitter. The design of those is simple and he surely should be able to tolerate the 3.5 dB or so of splitter loss. 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Friday, March 14, 2014 10:41 AM To: Charlie Cunningham; garyk...@wi.rr.com; 'Topband Mailing List' Subject: Re: Topband: Passive Receive Antenna Splitter All the TV splitters Ive taken apart are pure autotransformers with poor isolation. A VNA will show them deterioating and doing very little at 160M. It is simple enough to wind transformers for a splitter using 1/2 type 43 toroids. See this link that gives an excellent discussion and also shows the cheap way of doing it and the better way. Guess what is used in consumer grade CATV versions. http://www.minicircuits.com/app/AN10-006.pdf Both versions have been in handbooks for decades and I first started using them with Beverages in the mid 80's. Ive also used them as combiners and connecting various combinations of 2 Beverages with some very beneficial performance at times. Port to port isolation was very important to me. There are also several other on line versions, good and bad, if you do a Goggle for how to make a 2 way 50 ohm splitter Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: garyk...@wi.rr.com; 'Topband Mailing List' topband@contesting.com Sent: Thursday, March 13, 2014 9:41 PM Subject: 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 - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4336 / Virus Database: 3722/7192 - Release Date: 03/13/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
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
