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Reviews For: Diamond SG7900

Category: Antennas: VHF/UHF+ Omnidirectional: verticals, mobile, etc

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Review Summary For : Diamond SG7900
Reviews: 40MSRP: 119.99
2meter and 70cm mobile vertical
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
N4FME Rating: 2021-04-09
Gorilla Tape & shrink Wrap Time Owned: 0 to 3 months.
Performs great, butt folds over at 80 mph.
Gorilla Tape and shrink wrap took care of it.
W9VER Rating: 2020-09-25
GREAT PERFORMER, and delicate. Time Owned: 0 to 3 months.
Love the performance, it out performs the Larsen 5/8ths wave on 2 meters. When the corn gets high here in the Midwest, the gain on this antenna is enough to get though. Also it is very stiff so it stands upright on vehicle at highway speeds.

But is is so delicate, NO hitting tree branches with this one! All it takes is one hit and one of the coils loosens up. Quick repair with super glue, and I like how the part numbers are listed in the manual, however Diamond Antenna has poor support. They do not answer emails!
EI6DP Rating: 2019-03-13
Really One Great Antenna Time Owned: more than 12 months.
I have had this antennas now for neigh on 15 years +++ and it has never let me down or dropped in its performance. Its permanently mounted on my SUV and has hit many overhead branches, trees etc.

This week I plan to disassemble it for the first time since I bought it and give it a clean up etc plus straighten the top-end which is a little bent.

Would I buy one of these antennas again - YES, in a blink of an eye. They are really a great antennas and very robust with a long life of service.

AD5NM Rating: 2019-02-26
Outstanding Time Owned: more than 12 months.
It's been 19 years since I purchased my SG-7900 at R&L Electronics and it has seen a pretty rough life. I have yet to have a single issue with it. I have gone through a few mounts with it but the antenna itself has never given me a minute of grief. I anticipate another 19 years, if I live that long.

NV8G Rating: 2016-11-12
Almost Perfect Time Owned: more than 12 months.
I give the performance of this antenna the highest possible rating. I have two of these antennas, and have owned them for approx 2 years. Low swr throughout entire spectrum. However: They wont take ANY abuse at all. As some others in here have stated, I also have had to replace one of the coils. One hit in a parking garage and the the PLASTIC threads in the coil completely stripped and separated from the antenna. Parts were available, and I got great service from Diamond. But WHY, are they making a premium antenna with plastic threads? SO, now I am very careful about removing the antenna when I'm in parking garages, etc. If they would fix this problem ,this would be the very best mobile vhf/uhf antenna available.
AD0AR Rating: 2016-11-11
Thumbs up! Time Owned: more than 12 months.
Had this antenna for over 2 years now.
The unit I have has the UHF base.
Beat the heck out of it mobile, portable, and base. It has seen it all, including a dive off of the second story of my house. The fold over mechanism has a slight s-curve to it after the the big fall, but SWR is still good throughout both band ranges. I can't find a portable/mobile that can beat it's SWR range and performance for it's size. Plus it does work considerably well without a counterpoise/ground plane base for portable use. I have tried it with a magnetic base on the roof of my car when stationary and compared it to a tripod mount and observed no difference in performance. The size makes it useful for portable, mobile, and base station operations, but Mr. Obvious recommends the higher the antenna is erected, the better/farther the range.
When compared to my Diamond X-200A that replaced this, I found that the sg7900 also exhibits excellent commercial wideband coverage whereas the Diamond X-200A exhibited more attenuation on frequencies outside of the ham bands.
In God we trust, all others we monitor 73 de AD0AR
K2POL Rating: 2016-11-11
Stay away from it! Time Owned: 0 to 3 months.
I purchased and install the SG7900A-NMO at HRO New Castle, Delaware on 7 Oct 2016.

On 19 Oct 2016, I’m wrapping up my day at my second job. I open my hatchback as normal placing my day pack and lunch bag in the back of the car. As I lift the hatchback up, and just before it’s completely open I hear the antenna hitting the hood of my car. It took a moment for me to actually comprehend what had just happen…. disbelief, standing there in awe as I see recent purchase of 13 days ago broken before me. I have a Tarheel Srewdriver antenna, a Larson antenna, had a Comet SBB-7 55” antenna on the back of my 2012 Focus for 2 years, never an issue.

After seven phone calls, two answering machines, two short conversations (an Operator and Wayne), at least 3 emails with attachments to Brian I've received no return calls or emails from Diamond. I've given up on Diamond Antenna and their products - Customer service/support does not exist. Antenna was a good performer, flawed mechanics, poor customer support and you can forget about the warranty.
W9OS Rating: 2015-12-26
broken Time Owned: 0 to 3 months.
I was given this antenna after it ate a tree..
The base coil was broke in half.
Got it super glued back in shape.
Ohming out the base to the whip shows an open.
My SG 7500 shows the same.. Must be capacitance fed.
Also the very top coil shows open.Not sure if there is a capacitor in there or not?
The SWR is over 3:1 in 2M
Any info or help appreciated..

VE2CII Rating: 2014-09-15
best performing, worst quality Time Owned: more than 12 months.
This is probably the best mobile antenna on
the market as far as performance goes. The problem
is that it is one of the worst quality wise. There is a U-joint to allow it to fold over and the salt gets to that and eats it. There are no seals of any kind to prevent this. When the U-joint breaks the antenna is useless. I have this antenna for 20 years and it never sees winter or any kind of weather salt environment. All teh diamond SG series
suffer from the same malady.
KC5ONZ Rating: 2014-06-09
Thread Stripping Time Owned: more than 12 months.
This is the second SG7900 I have owned in the past 2+ years. Both have had the threads at where the coils attach strip on the small plastic portion. This is a known problem that Diamond appears to not want to deal with. Good antenna other wise if this problem could be dealt with.