GRA-MAT50 MK2 Counterpoise Magnetic Mat Ground Plane for Magnetic Mount & HF Antenna

Great product. I have 3

Quite functional, works well to adjust a mobile antenna's ground plain and general experimentation. The magnetic pad sticks well to my car for good contact. It's easy to install and remove so it's portable. I've used mine for weeks now and I must say that I have seen changes in signal strength based on frequency and antenna. Do your research first.

Great item that arrived in only 7 days from America.

I use the GRA-MAT50 MK2 with my Yaesu ATAS-120A antenna on a mag mount in the center of my minivan roof. Before connecting the GRA-MAT50 to the antenna, my SWR on 40 meters was about 2.3:1, which is not terrible, but could be better. Once I connected the GRA-MAT50 to the antenna, my SWR on 40 meters went down to about 1.4:1, which is pretty good. I did not notice any improvement in SWR on other bands (10,12,15,17,and 20 meters) because the Yaesu ATAS-120A is able to tune those bands good on its own without the GRA-MAT50. But the improvement on 40 meters makes this purchase worth it. A friend of mine also uses the Yaesu ATAS-120A on a mag mount and he has the same higher SWR problem on 40 meters. So he is considering the purchase of the GRA-MAT50 to help with 40 meter SWR. Even though the GRA-MAT50 did not make a difference on bands other than 40 meters with my Yaesu ATAS-120A, it might help with my transmit signal somewhat anyway by creating a more efficient counterpoise by helping to increase the capacitive coupling of the antenna to the vehicle.. I have another mag mount antenna, (Hustler MO-2 with resonators) but I have not tested the GRA-MAT50 with that antenna. If I do test it with that antenna, I will submit that review. I would think that the GRA-MAT50 may probably help with that antenna too since the bandwidth with the Hustler MO-2 on a mag mount is quite narrow on 40 meters, and the internal tuner of the radio is not able to get the SWR real low on 40 meters. So, what is generally known about a mag mount antenna on the HF bands, the lower in frequency that you get, the less effective a mag mount antenna can be, most notably 7 mHz or lower. But the GRA-MAT50 can help with that. Bottom line, I recommend the GRA-MAT50, especially for 40 meters.

Rather disappointed as the magnet on it is very weak, it would not hold on a car but i have it fitted on a metal roof, will see if it helps the SWR, not going to return it as i bought it from the usa.