Topics

DIAMOND SG-7900A-NMO for my mobile rig?


Herb - KM6JBI
 

I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI


Gary - KB7QWC
 

Herb, how high is the SWR and what model glass mount did you have?

I have considered a glass mount for my 2016 Silverado so very interested.

Thanks,

 

   …Gary, KB7QWC

 

 

I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI


carl.wf6j@gmail.com
 

Guys,

Save your money… glass mounts are not the way to go.

73,
Carl, WF6J

On Sep 27, 2020, at 3:40 PM, Gary - KB7QWC <kb7qwc@...> wrote:

Herb, how high is the SWR and what model glass mount did you have?
I have considered a glass mount for my 2016 Silverado so very interested.
Thanks,
 
   …Gary, KB7QWC
 
 
I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI 



Greg D
 

They're certainly a compromise, but I've used one on two different cars, and it's worked well enough.  The radiation pattern wasn't ideal, but the SWR was generally fine.  And on the current car, it's really the only acceptable solution, given the car's construction.

I'm curious why the SWR is high.  What brand of antenna, where is it mounted, what sort of glass is (er, was) it attached to?

Greg  KO6TH


Guys,

Save your money… glass mounts are not the way to go.

73,
Carl, WF6J

On Sep 27, 2020, at 3:40 PM, Gary - KB7QWC <kb7qwc@...> wrote:

Herb, how high is the SWR and what model glass mount did you have?
I have considered a glass mount for my 2016 Silverado so very interested.
Thanks,
 
   …Gary, KB7QWC
 
 
I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI 



Brian Gohl - AI6US
 

Good antenna with great perfomance. In my opinion, the fold over feature is indispensable when driving under low hanging trees and in parking garage, etc. Quick and easy to fold down.

Best Regards! 
Brian Gohl - AI6US 
(916) 770-7751 cell


-------- Original message --------
From: Herb - KM6JBI <hpgarcia70@...>
Date: 9/27/20 2:30 PM (GMT-08:00)
To: sfarc@w6ek.groups.io
Subject: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI
--
Brian- AI6US


Al - WB6RUU
 

I have 2 of these diamond antennas on my vehicles with an FTM400. They work well on both bands. They’re well constructed and I believe will give you many years of service.


On Sep 27, 2020, at 6:19 PM, Greg D <ko6th.greg@...> wrote:

They're certainly a compromise, but I've used one on two different cars, and it's worked well enough.  The radiation pattern wasn't ideal, but the SWR was generally fine.  And on the current car, it's really the only acceptable solution, given the car's construction.

I'm curious why the SWR is high.  What brand of antenna, where is it mounted, what sort of glass is (er, was) it attached to?

Greg  KO6TH


Guys,

Save your money… glass mounts are not the way to go.

73,
Carl, WF6J

On Sep 27, 2020, at 3:40 PM, Gary - KB7QWC <kb7qwc@...> wrote:

Herb, how high is the SWR and what model glass mount did you have?
I have considered a glass mount for my 2016 Silverado so very interested.
Thanks,
 
   …Gary, KB7QWC
 
 
I'm looking at the Diamond SF-7900A-NMO for my Yaesu FTM 400XDR. Any thoughts? The glass mount antenna's SWR is to high. So, I decided to remove it and buy , third brake light antenna mount from Bullet Proof Diesel.

Herb  KM6JBI 



Herb - KM6JBI
 

Gary,

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

I hope you have better luck than I did.

--
Herb Garcia, KM6JBI


Gary - KB7QWC
 

Hmmm, I’ll have to rethink this!

Thanks,

 

   …Gary

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Herb - KM6JBI
Sent: Sunday, September 27, 2020 7:41 PM
To: sfarc@w6ek.groups.io
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Gary,

 

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

 

I hope you have better luck than I did.


--

Herb Garcia, KM6JBI


Greg D
 

An SWR of 6.something suggests that something is not connected, or not connected properly.  Mine was only that bad when I had the inside blob mounted 90-degrees from where it was supposed to be.

I don't have any sort of adjustment on mine.  What model do you have?

Greg  KO6TH


Gary - KB7QWC wrote:

Hmmm, I’ll have to rethink this!

Thanks,

 

   …Gary

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Herb - KM6JBI
Sent: Sunday, September 27, 2020 7:41 PM
To: sfarc@w6ek.groups.io
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Gary,

 

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

 

I hope you have better luck than I did.


--

Herb Garcia, KM6JBI



Herb - KM6JBI
 

Greg,

MFJ-1734. There was hardly any instructions that came with the antenna. I'm pretty disappointed with that antenna.

~Herb


On Sun, Sep 27, 2020, 9:51 PM Greg D <ko6th.greg@...> wrote:
An SWR of 6.something suggests that something is not connected, or not connected properly.  Mine was only that bad when I had the inside blob mounted 90-degrees from where it was supposed to be.

I don't have any sort of adjustment on mine.  What model do you have?

Greg  KO6TH


Gary - KB7QWC wrote:

Hmmm, I’ll have to rethink this!

Thanks,

 

   …Gary

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Herb - KM6JBI
Sent: Sunday, September 27, 2020 7:41 PM
To: sfarc@w6ek.groups.io
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Gary,

 

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

 

I hope you have better luck than I did.


--

Herb Garcia, KM6JBI



Gary - KB7QWC
 

Well folks, have a good evening.

Our power is off here and I’m about ready to turn the generator off and hit the rack.

73,

   …Gary, KB7QWC

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Gary - KB7QWC via groups.io
Sent: Sunday, September 27, 2020 9:49 PM
To: sfarc@w6ek.groups.io; hpgarcia70@...
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Hmmm, I’ll have to rethink this!

Thanks,

 

   …Gary

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Herb - KM6JBI
Sent: Sunday, September 27, 2020 7:41 PM
To: sfarc@w6ek.groups.io
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Gary,

 

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

 

I hope you have better luck than I did.


--

Herb Garcia, KM6JBI


carl.wf6j@gmail.com
 

Sorry to hear that. In the past, PG&E shut down users, but left ON the high tension lines.  Same as the one that started the Paradise fire.  If you look at the video, the wire/fire was spotted early on, yet ignored as it was “way up on a steep hillside”. Not more than an hour later it turned into the monster as we know it.

PG&E put out a PR thing that at the last power out, they inspected all the lines before turning them back on. They had discovered “several lines” that were blown down by branches and other reasons.  sThere was no indication those “problems” had been fixed prior to the turn on.

Not picking on PG&E, just their “record” of their actions.

73, Carl, WF6J

Sorry your power is out.

On Sep 27, 2020, at 10:11 PM, Gary - KB7QWC <kb7qwc@...> wrote:

Well folks, have a good evening.
Our power is off here and I’m about ready to turn the generator off and hit the rack.
73,
   …Gary, KB7QWC
 
From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Gary - KB7QWC via groups.io
Sent: Sunday, September 27, 2020 9:49 PM
To: sfarc@w6ek.groups.io; hpgarcia70@...
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?
 
Hmmm, I’ll have to rethink this!
Thanks,
 
   …Gary


Greg D
 

Ah.

The one I have is the Larsen 2/70 from, er, a while ago.  I think I got it back in the 90's (aka last century), but it looks like they're still selling it ($140 on Gigaparts).  Still working fine.  There appear to be other brands a lot cheaper, but unknown how well they work.

A big factor is the glass through which they're passing RF through.  If it's tinted in any way, that's a problem.  The tinting is usually a thin layer of metal, which really messes up the capacitive coupling.

Drilling a hole for an NMO mount always works, if you have a place for it.

Greg  KO6TH


Herb Garcia wrote:

Greg,

MFJ-1734. There was hardly any instructions that came with the antenna. I'm pretty disappointed with that antenna.

~Herb

On Sun, Sep 27, 2020, 9:51 PM Greg D <ko6th.greg@...> wrote:
An SWR of 6.something suggests that something is not connected, or not connected properly.  Mine was only that bad when I had the inside blob mounted 90-degrees from where it was supposed to be.

I don't have any sort of adjustment on mine.  What model do you have?

Greg  KO6TH


Gary - KB7QWC wrote:

Hmmm, I’ll have to rethink this!

Thanks,

 

   …Gary

 

From: sfarc@w6ek.groups.io <sfarc@w6ek.groups.io> On Behalf Of Herb - KM6JBI
Sent: Sunday, September 27, 2020 7:41 PM
To: sfarc@w6ek.groups.io
Subject: Re: [from W6EK Groups.io] DIAMOND SG-7900A-NMO for my mobile rig?

 

Gary,

 

The highest it was six point something and the lowest was about three point five. There is a dial on the inside piece of the glass mount. Dustin adjusted it down to the lowest we could get it. The issue as the cable moves around the SWR fluctuates.

 

I hope you have better luck than I did.


--

Herb Garcia, KM6JBI