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Reviews For: MFJ 812B

Category: SWR & Wattmeters & Dummy Loads

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Review Summary For : MFJ 812B
Reviews: 4MSRP: 34.95
SWR watt meter from MFJ
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
KI4GTJ Rating: 2012-01-10
Works great on 220MHz Time Owned: 3 to 6 months.
Well as my other post says it works great now I have been able to test it out on the jetstream JT220m same antenna (sbb224) just on the 220 end SWR on 220 at 25watt is about 1.4:1 and at 50watt 1.6:1 not bad for a mag mount on a cookie sheet I only run it on 25watts or less for the way I have to use it in the apartment! The mfj-921 will be the next to test

Earlier 5-star review posted by KI4GTJ on 2011-12-24

works great used it to test the SWR on the comet sbb-224 using an ft-817 on 2m with amp comes up 35w with swr 1.3:1 cant beat it on a mag mount on a cookie sheet out side
KK4BH Rating: 2006-04-28
Works Perfect For Me Time Owned: more than 12 months.
I have owned a MFJ-812B SWR/Power Meter for over 5 years and it has worked as it should all this time. I was looking for a inexpensive 2 meter SWR meter at a time when I was building a J-pole antenna. At that time I was using a IC-2100H and this meter made it easy to adjust the antennas SWR. Also, the forward power readings closely coincided with the 3 different power levels of the 2100H. Since then I have used this meter with a 706MK2, 746, and presently a 706MK2G without any problems. It handled the 100 watts from my 746 fine. It was also used to adjust the SWR of a Ringo Ranger 2 and check the SWR of my present antenna, a Diamond X50A.

In coclusion, I have used many SWR/Power Meters during my 45 years of hamming and find this one to perform as it should.

AB0RE Rating: 2006-04-28
Ditto the previous review Time Owned: more than 12 months.
There are a considerable amount of reviews for this product in a different category:

I also owned this product and it is the worst piece of ham equipment I have ever laid hands on. It did not work *at all* and it caused me to ruin a couple antennas by over-trimming before I realized the problem was the 812B. The meter, no matter how much I'd trim, would not show any changes to reflected power.

I'd have dropped a brick on it but it wasn't worth causing possible damage to the brick.

Dan / ab0re
KC9GUZ Rating: 2006-04-28
Freaking POS from HE**!!! Time Owned: more than 12 months.
Causes my Icom 746 to fold back power to 25 watts from 100 watts on 2 meter FM!! I hooked the radio itself only to a dummy load and all was fine. Checked my jumpers and connectors all was fine. Inline between the radio and the meter the swrs on the swr meter on the 746 showed a 2.5=1 swr. I hooked my jumpers just to the rig along with my dummy load and all was well. The stupid MFJ meter causes my swrs to reflect! The SWR meter shows false SWR readings as well and the power measurements are a joke.. I cant believe a big company like MFJ contunually produces sub standard products and components to the amateur community CONTINUALLY gets away with it.. Another sad fact is they now own Hy Gain and Ameritron and from what i hear they are junking up their stuff as well.. I cringe every time i see a unsuspecting or a new ham buy MFJ stuff at a hamfest. :-(