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Duplexer


JamesBrox

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19 minutes ago, Sshannon said:

Watch this to see the problem with 90° connectors (except silver plated amphenol ones).

 

 

10 minutes ago, Sshannon said:

Got it. Thanks. I may start another tech topic on jumpers that are used with folks who have repeater stations....that such be interesting. 

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41 minutes ago, Sshannon said:

I’m going to go work on my cabin. I’ll check in later.  

When you get time. Give me your break down on your repeater set up. Radio(s), Cables, Duplexer, Tower, Antenna(s).... everything please. If I can't figure this out, I'll just copy. Lol. Thanks   

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17 minutes ago, JamesBrox said:

When you get time. Give me your break down on your repeater set up. Radio(s), Cables, Duplexer, Tower, Antenna(s).... everything please. If I can't figure this out, I'll just copy. Lol. Thanks   

I don’t have a repeater. I’m just a retired engineer and a ham. 

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17 hours ago, JamesBrox said:

Just tell me your set up. How are you currently communicating to the GMRS community in your area?

 

There’s no GMRS community (or GMRS repeaters) here (Butte, MT) but I’m active on 2 meter and 70 cm using a Radioddity DB20G. I am also active on HF using a Yaesu FTDX10 (160-6 meters @ 100 watts), with a short RG213 (HF has far less losses than UHF) running to my SWR/Wattmeter, then a six foot ABR400 jumper to a window pass-thru, which would really be bad in UHF). From the other side of the pass-thru is a 15 foot jumper to the 49:1 unun which is connected to my 66 foot wire which is 30 feet up on a Spiderbeam fiberglass mast.

My BS and MS are in Engineering Science with an emphasis on controls, my PE (engineering license) is in electronic engineering but I worked on a section crew for Burlington Northern one summer. 😃

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2 minutes ago, Sshannon said:

There’s no GMRS community (or repeaters) here (Butte, MT) but I’m active on 2 meter and 70 cm using a Radioddity DB20G. I am also active on HF using a Yaesu FTDX10 (160-6 meters @ 100 watts), with a short RG213 (HF has far less losses than UHF) running to my SWR/Wattmeter, then a six foot ABR400 jumper to a window pass-thru, which would really be bad in UHF). From the other side of the pass-thru is a 15 foot jumper to the 49:1 unun which is connected to my 66 foot wire which is 30 feet up on a Spiderbeam fiberglass mast.

My BS and MS are in Engineering Science with an emphasis on controls, my PE (engineering license) is in electronic engineering but I worked on a section crew for Burlington Northern one summer. 😃

Sounds awesome. I like the BN. Really? No GMRS in your area? You sound overqualified to be on an GMRS forum. Any reason you're a major contributor here? 

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2 minutes ago, JamesBrox said:

Sounds awesome. I like the BN. Really? No GMRS in your area? You sound overqualified to be on an GMRS forum. Any reason you're a major contributor here? 

I’m active in amateur rocketry and we use GMRS radios to keep track of each other when we’re recovering rockets. My GMRS radios are a Garmin Rhino 700, a couple of old Motorola FRS/GMRS handhelds, a couple Midland combo units, and one of the two DB20G radios that I have. My other one has been configured as a dual band ham radio. 
During the pandemic I started watching videos (too much) and I found those of Notarubicon enjoyable and interesting. Unlike some I enjoyed his dry humor.
So I got my GMRS license. I had been planning to anyway, but never got around to it. That led to an awakened interest in radios in general which led me to get my ham license. 
I don’t really remember how I found this forum but I’ve enjoyed it. I’m not active on any ham radio forums. I haven’t even visited any other than a couple group.io pages specific to my radios. Radio is radio and I find it fascinating. 

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27 minutes ago, Sshannon said:

I’m active in amateur rocketry and we use GMRS radios to keep track of each other when we’re recovering rockets. My GMRS radios are a Garmin Rhino 700, a couple of old Motorola FRS/GMRS handhelds, a couple Midland combo units, and one of the two DB20G radios that I have. My other one has been configured as a dual band ham radio. 
During the pandemic I started watching videos (too much) and I found those of Notarubicon enjoyable and interesting. Unlike some I enjoyed his dry humor.
So I got my GMRS license. I had been planning to anyway, but never got around to it. That led to an awakened interest in radios in general which led me to get my ham license. 
I don’t really remember how I found this forum but I’ve enjoyed it. I’m not active on any ham radio forums. I haven’t even visited any other than a couple group.io pages specific to my radios. Radio is radio and I find it fascinating. 

I get that. I like rocketry too. Done it as a kid. Good times. My question is why waste your time on this lowly gmrs forum? Your ham license gives you way more of the RF spectrum then this simple UHF spectrum. 

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17 minutes ago, JamesBrox said:

I get that. I like rocketry too. Done it as a kid. Good times. My question is why waste your time on this lowly gmrs forum? Your ham license gives you way more of the RF spectrum then this simple UHF spectrum. 

I don’t feel like GMRS is lower than ham and I enjoy the people here. 🙂

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I have a Repeater and my Repeater setup is as follows:

Repeater - Vertex Standard EVX - R70-G7 403-470 MHz 40-Watt Analog/Digital - Tx - 462.625 MHz/Rx - 467.625 MHz

                   Receiver Port Connector - Female BNC

                   Transmitter Port Connector - Female "N" Connector

Antenna - Laird FG4605 5 dB Omni-Directional tip at 30 Feet AGL

                  Transmission Line - Times Microwave LMR400 27 Feet Total Run from the Polyphaser to a Termination Point at                       the Duplexer.  From the Polyphaser to the Female "N" Connector at the base of the Antenna approx. 20 Feet,                         including a drip loop, not to exceed total length of 25 Feet.

                   Polyphaser Lightning Arrestor with Gound to Existing Earth Grounding Point with 8 Gauge Wire.

Duplexer - EMR Corp #65316-0/MC(5G) - six cavity duplexer with female "N" Connector ports.

Duplexer Jumper Cables - Times Microwave Low Loss RG-8X Coaxial Bulk Cable 100 Feet in length ordered.

                   Receive High Port - 14 Inch Cable Length with Amphenol #112533 BNC Male Solderless Connector (Repeater)                      and Amphenol # 172135 "N" Male Solderless Connector (Duplexer Connector)

                   Transmit Low Port - 12 Inch Cable Length with Amphenol #172135 "N" Male Solderless Connectors on both                           ends.

                   Antenna Port - 12 Inch cable length with Amphenol #172135 "N" Male Solderless Connector (Duplexer) and                           Amphenol #18211510 PL259 UHF Male Solderless Connector to Mate with Antenna Transmission Feedline with                     an Amphenol #AML-83-1J Double UHF Barrel Connector.  (The Antenna Installer did not have a Female "N"                           Connector for a LMR400 Cable at the time of install so I was stuck with the PL259 UHF Male Connector)

NOTE:  ALL JUMPER CABLES WERE FABRICATED/ASSEMBLED BY A LOWLY LICENSED GMRS USER (ME) IN THE OLD                       PEOPLE COMMUNITY OF SUN CITY WEST ARIZONA

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27 minutes ago, Sshannon said:

I don’t feel like GMRS is lower than ham and I enjoy the people here. 🙂

You may not but there's folk that do here. Those who have a ham license yet that's not enough...they feel they need to come here and complainant things with their knowledge, you see them on every thread, yet don't even have a gmrs repeater (not even entry level like those suitcase styles.... it's crazy.)  

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14 minutes ago, nokones said:

I have a Repeater and my Repeater setup is as follows:

Repeater - Vertex Standard EVX - R70-G7 403-470 MHz 40-Watt Analog/Digital - Tx - 462.625 MHz/Rx - 467.625 MHz

                   Receiver Port Connector - Female BNC

                   Transmitter Port Connector - Female "N" Connector

Antenna - Laird FG4605 5 dB Omni-Directional tip at 30 Feet AGL

                  Transmission Line - Times Microwave LMR400 27 Feet Total Run from the Polyphaser to a Termination Point at                       the Duplexer.  From the Polyphaser to the Female "N" Connector at the base of the Antenna approx. 20 Feet,                         including a drip loop, not to exceed total length of 25 Feet.

                   Polyphaser Lightning Arrestor with Gound to Existing Earth Grounding Point with 8 Gauge Wire.

Duplexer - EMR Corp #65316-0/MC(5G) - six cavity duplexer with female "N" Connector ports.

Duplexer Jumper Cables - Times Microwave Low Loss RG-8X Coaxial Bulk Cable 100 Feet in length ordered.

                   Receive High Port - 14 Inch Cable Length with Amphenol #112533 BNC Male Solderless Connector (Repeater)                      and Amphenol # 172135 "N" Male Solderless Connector (Duplexer Connector)

                   Transmit Low Port - 12 Inch Cable Length with Amphenol #172135 "N" Male Solderless Connectors on both                           ends.

                   Antenna Port - 12 Inch cable length with Amphenol #172135 "N" Male Solderless Connector (Duplexer) and                           Amphenol #18211510 PL259 UHF Male Solderless Connector to Mate with Antenna Transmission Feedline with                     an Amphenol #AML-83-1J Double UHF Barrel Connector.  (The Antenna Installer did not have a Female "N"                           Connector for a LMR400 Cable at the time of install so I was stuck with the PL259 UHF Male Connector)

NOTE:  ALL JUMPER CABLES WERE FABRICATED/ASSEMBLED BY A LOWLY LICENSED GMRS USER (ME) IN THE OLD                       PEOPLE COMMUNITY OF SUN CITY WEST ARIZONA

DANG!!! That's what I want! Hard facts. 

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1 hour ago, Sshannon said:

Absolutely!
I would never argue against something that’s up and working!  Ask Kenny if he would do anything differently.

Yeah, looks right to me as well.  I would have used a different antenna line (LDF4-50 hardline) but I have thousands of feet of it on hand and connectors for it so it's not just cheaper for me (I don't have nearly that much LMR400) it's actually free for the most part. 

 

If you happen to have a dummy load that you could connect to the duplexer in place of the antenna I would be interested to see what your power readings were with a dummy load on the antenna port on the duplexer.

 

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1 hour ago, Sshannon said:

Absolutely!
I would never argue against something that’s up and working!  Ask Kenny if he would do anything differently.

I'm asking you. I see your name pop up all the time, no matter what the topic. With you being a ham on a gmrs forum....what makes his system work so well? 

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47 minutes ago, JamesBrox said:

I'm asking you. I see your name pop up all the time, no matter what the topic. With you being a ham on a gmrs forum....what makes his system work so well? 

Well, the truth is the antenna system more than ANYTHING else.  You can have the most expensive repeater on the planet with an antenna at 50 feet and I can out distance you with a couple garage sale M120 radius radio's and a repeater link cable and an antenna that's 400 feet in the air.  And you have to understand there are three measurements of height when it comes to all this out.  First measurement is AGL.  That means Above Ground level.  If the antenna is on a 300 foot tower but mounted at 200 feet the antenna is 200 feet AGL.  Then there is AMSL or Above Mean Sea Level.  That is the height at the ground where the tower is above sea level PLUS the AGL level of the antenna.  Then the most important one that is really important. That one is HAAT.  Height Above Average Terrain.  Now this one you are not going to measure with a tape measure.  It's a multipoint averaging calculation.  To figure this out, you create a circle around a tower out to some distance.  I believe the FCC uses 20 miles but it could be more.  Then you draw circles within that circle, typically 5 that are equally spaced.  Then you draw a cross and an X through the circles to create the points of reference.  The lines can vary from every 22.5 degrees to every 5 degrees depending on the type of calculation you want to do.  You then get a topographical map of the area in the circle and document the ground level heights at every one of the intersecting points on the map.  Add all those together, divide by the number of readings and then subtract the number from your AMSL.  That will give you HAAT.  The FCC website will do this for you, so don't think  you need to do it manually. 

This is why an antenna on a 500 foot tower that sit's in a 1500 foot deep valley can be out talked by an antenna on a 10 foot mast pipe on any top ridge of the peaks above that valley.  Sure the 500 foot antenna will talk gangbusters in that valley, but not at all outside it.  And the 10 foot one will talk then entire valley plus down into all the neighboring valleys. 

 

We have one repeater on the MidWest system (Crete600) that talks 120 miles across it's coverage area.  I have personally verified this by starting in Chicago and driving over half way to Indy before I fell out of the coverage area of that repeater.  And it all has to do with the height of the antenna. 

Interesting EXTREME example of this.  Ham radio has satellites that are repeaters.  The repeaters are limited at 2 to 4 watts.  They are 200 plus miles above the earth and you can hear them on a portable radio (HT) with a meager beam antenna.  And you can also talk on them with the same portable radio and beam antenna.

 

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