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Reviews For: MTFT -Germany

Category: Antenna parts, accessories, incl. baluns, hardware, etc.

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Review Summary For : MTFT -Germany
Reviews: 4MSRP: 39GBP
Description:
Magnetic balun No 11370
Product is in production
More Info: http://www.wimo.com
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0042.8
KD7RDZI2 Rating: 2020-02-09
A good product Time Owned: more than 12 months.
I will comment on the WIMO Model 11370 which is not weatherproof. Use additional protection, i.e. a plastic box, when using outdoors is advised.

Although I would need another unit to actually test its power efficiency having now an antenna analyzer I think I have a better understanding now than before. The inside seems a voltage unun with a ferrite core. According to the Jerry Sevick book these type of transformer are fine below 10Mhz, not so much at higher frequencies. However the wiring here is twisted and spaced differently.
I had rudimentary tested this unit with the analyzer. Without any load connected a lossy transformer would show a low SWR (5 or less). I could not even measure the SWR on HF on my analyzer, so this a good sign. On my Mini60 analyzer the SWR lowers on the 6m band at around 7 so, in my view, it might start to become less efficient from 6m (to actually test its efficiency one should connect a TX to two transformers a power meter and a dummy load).
Connecting the transformer to a 500 small resistor the SWR was close to 1 over the all HF so this shows it should actually be wideband.

Overall I think it might be a bit expensive for what it is but I think it works as advertised at least on HF.
GM0URD Rating: 2012-09-27
Could be improved Time Owned: 0 to 3 months.
Took my 11370 apart before using. The output terminal inside the balun is bare copper wire so I added a small eyelet solder tag & tightened it up securely. The manufacturers leaflet describes it as a 1:10 ratio balun but it appears to be a 1:9 ratio one. The three balun windings each going through the centre of the toroid nine times. The toroid seems to be a bit small for the number of windings as two turns overlap. Baluns work best when only about two thirds of the ferrite material is wound leaving a gap. The one thing that I will say in the baluns favour is that the center winding of the three goes to the antenna output terminal. This should maximize the coupling from the windings on either side. This unit is not waterproof and I would not use it on say 100 Watts. If you can please refer to page 84 of the February edition of RadCom which describes a similar type 1:9 balun used as an EME antenna. This antenna design by GM4UTP however is terminated at the end of the long wire by a non inductive resistor of between 700 ohms and 2 kilo ohms. This suggests that the MTFT 11370 range of baluns could also be used in this way with the terminating resistor connected to earth. Note also that the outer metal body of this balun has no internal connection and appears to be for cooling only. If you have one of these it is worth having a look inside it. You never know you may well be able to make a better one yourself.
ON4WIY Rating: 2010-08-09
BIG 0 ! Time Owned: 0 to 3 months.
Keep your hands of! swr.... not good on any band.
I'll tried several configurations and after a couple days I gave it up !
The same problem by my friend so I'am not alone....
We also tried with 20 m long wire agn 0.
So we decided to give it away to a swl his experience was the same :not good at all just junk!!!
Save your money and make some homebrew stuff.
G0CJM Rating: 2006-11-01
Excellent value Time Owned: 0 to 3 months.
Taken delivery of the above today. Designed to be fitted between tx/rx coax and wire indoors. With the exception of 7Mhz It has tuned with a 1:1:5 swr from 1.8-50Mhz For me, with a ver small garden only fifteen feet in diameter, this is great. May i recommend its use to others. The wire must be at least 20ft long.