Re: [amsat-bb] Attaching the coax to antenna boom
This is quite curious.
Page 1 of the WA5VJB paper says, "Run the coax back down the antenna and along the boom keeping the radius small..." His hand-drawn illustration shows the feedline going down the boom then making a hard turn at the boom-to-cross arm plate.
The M2 instruction sheets for the 2MCP8A and 436CP16 antennas both state (in bold type), "Do not route feedline to boom to mast plate as exiting antenna here will adversely affect circular field."
Mr. Britain's paper is obviously focused on mounting the cross bar somewhere along the boom of a somewhat long antenna. The M2 instructions are for mounting short antennas from the back of the boom to the cross bar. Not the same situation. But, for a newbie like me, the definitive conclusion to this discussion is...I am still confused.
I was hoping to hang my M2 LEO antennas Monday morning but now not until after I call the M2 support line for their read on this.
73, Frank
FRANK W. KARNAUSKAS, N1UW ARRL MINNESOTA AFFILIATED CLUB COORDINATOR AMSAT NEWS SERVICE ROTATING EDITOR 1402 SUMMIT SHORES DR. BURNSVILLE, MN 55306 [email protected] 612-644-9174
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Gary Sent: Sunday, March 17, 2019 2:29 PM To: radiomb; [email protected] Subject: Re: [amsat-bb] Attaching the coax to antenna boom
Yes, you can, just pay attention to how far your coax turn is from your driven element. There are a couple spots to avoid.
It is pretty well explained in Kent Britain's (wa5vjb) paper here: http://www.kk0sd.net/metalboom/metalboom.htm
73, Gary kk0sd
-----Original Message----- From: AMSAT-BB [email protected] On Behalf Of radiomb Sent: Sunday, March 17, 2019 4:04 PM To: [email protected] Subject: [amsat-bb] Attaching the coax to antenna boom
Building my new ground station and another question. I have always only elevated my antenna 90 degrees. I loose about 20 25 seconds while the azimuth rotator turns 180 degrees to track the rest of the pass. I have just let the coax hang off the back of the antennas in a big loop. I am afraid it will get hung up going 180 degrees. Question, Can I attach the coax to the antenna boom and run it back until it gets to the cross boom or will that throw off the radiation pattern? Thanks 73 Mike K4MIA
_______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Hi all I´m in the same situation, this summer I´ll mont my pair of M2 with separate feedlines for V and U, I´m going to use a good 7mm coax cable routing across de boom, because routing to the back itcomplicates my assembly a lot and adds extra weight to the back. I hope it does not distort my radiation pattern too much 73 Luis EC4TR
El lun., 18 mar. 2019 a las 6:27, Frank Karnauskas ([email protected]) escribió:
This is quite curious.
Page 1 of the WA5VJB paper says, "Run the coax back down the antenna and along the boom keeping the radius small..." His hand-drawn illustration shows the feedline going down the boom then making a hard turn at the boom-to-cross arm plate.
The M2 instruction sheets for the 2MCP8A and 436CP16 antennas both state (in bold type), "Do not route feedline to boom to mast plate as exiting antenna here will adversely affect circular field."
Mr. Britain's paper is obviously focused on mounting the cross bar somewhere along the boom of a somewhat long antenna. The M2 instructions are for mounting short antennas from the back of the boom to the cross bar. Not the same situation. But, for a newbie like me, the definitive conclusion to this discussion is...I am still confused.
I was hoping to hang my M2 LEO antennas Monday morning but now not until after I call the M2 support line for their read on this.
73, Frank
FRANK W. KARNAUSKAS, N1UW ARRL MINNESOTA AFFILIATED CLUB COORDINATOR AMSAT NEWS SERVICE ROTATING EDITOR 1402 SUMMIT SHORES DR. BURNSVILLE, MN 55306 [email protected] 612-644-9174
-----Original Message----- From: AMSAT-BB [mailto:[email protected]] On Behalf Of Gary Sent: Sunday, March 17, 2019 2:29 PM To: radiomb; [email protected] Subject: Re: [amsat-bb] Attaching the coax to antenna boom
Yes, you can, just pay attention to how far your coax turn is from your driven element. There are a couple spots to avoid.
It is pretty well explained in Kent Britain's (wa5vjb) paper here: http://www.kk0sd.net/metalboom/metalboom.htm
73, Gary kk0sd
-----Original Message----- From: AMSAT-BB [email protected] On Behalf Of radiomb Sent: Sunday, March 17, 2019 4:04 PM To: [email protected] Subject: [amsat-bb] Attaching the coax to antenna boom
Building my new ground station and another question. I have always only elevated my antenna 90 degrees. I loose about 20 25 seconds while the azimuth rotator turns 180 degrees to track the rest of the pass. I have just let the coax hang off the back of the antennas in a big loop. I am afraid it will get hung up going 180 degrees. Question, Can I attach the coax to the antenna boom and run it back until it gets to the cross boom or will that throw off the radiation pattern? Thanks 73 Mike K4MIA
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
On 2019-03-18 4:16 AM, EC4TR Luis wrote:
I´m in the same situation, this summer I´ll mont my pair of M2 with
Well I have both my M2 antennas mounted as the paper says. You have to place them in an X formation and route the coax as shown. They have worked well for me probably 10 years now.
participants (3)
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Bill Booth -
EC4TR Luis -
Frank Karnauskas