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Korer 9.2 matching transformer

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  • Korer 9.2 matching transformer

    A few years ago I bought the Korer 9.2 FM antenna. It has worked pretty well. The F/B is especially nice. I do wish it did have a bit more forward gain, but it does pretty well considering the size.
    The antenna signal had dropped off a bit. I figured conditions, but it went on and on. I took it down and I found a crack in the matching transformer circuit board. I soldered it. Where the ground side is connected to the board. I guess it is okay, but I have no clue. The continuity using my ohm meter seems to say it is working. Since the board is small and it just converts the 300ohm to 75ohm, could I replace the matching transformer with like a CM 94444? I have not tried it, but I presume any good matching transformer should do the job. Anyone try it? Getting a new one from Germany may not be easy, if I could get a new one.
    The wing nuts are rusty after being up there in our weather, but I don't see any issue with that as the elements are insulated from the boom.
    Thanks for your help.

    I have read that some matching transformers are set more for UHF, rather than FM. Is this true? If so, does it make any difference?
    Last edited by mwdxer; 07-01-2020, 04:35 AM.

  • #2
    Yes, you can replace it with the CM-94444 outdoor matching transformer. Since digital TV on the low-VHF band starts at 54 MHz, there will be no
    problem using it on the FM band. It is a good idea to replace your matching transformer once a year if you live in a harsh environmental areas.
    They are cheap at $5. I have not come across any information that some U/V/FM matching transformers are for UHF only.

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    • #3
      I found out our local Home Depot has a supply of the CM 94444 transformers for $5 a piece. Those are supposed to be the best other than making your own. I also found some RG11 I could use to replace the RG6. Even though I am running only about 85 feet, it looks like I would gain a bit over 1 DB. I may do some testing with one Sony radio I have and run 15 feet of coax to the radio from out in the yard below the Korner 9.2 and see if a short piece of RG6 will give me more gain. Brian suggested raising the antenna, but with our winds, I do not want to take a chance on hurting the antenna. My only other choice would be spend a lot with a crank down tower.. Guy wires are not practical here. Thanks for the reply. You are right a matching transformer in our elements, it does not last long.

      Update: Last evening I took the Korner 9.2 down and I replaced the matching transformer with a CM 94444. I put it back up only to find a drop in signal! Apparently the Korner 9.2 circuit board is tailored to the antenna. I was quite surprised to say the least. I eeven shortened the leads on the 94444, so they would just connect across the screw terminals too. I re-hooked up the circuit board and put it back and the signal was back. I have noticed a drop in signal the past few weeks. I checked the antenna, it is fine, no shorts, bad connections, etc. I even took the Sony HD Radio out and ran a 25 foot piece of RG6, and I did notice very very slight increase, but hardly noticeable.At least it seemed to be a hair stronger, but I am splitting hairs.I only run about 57 feet of RG6 from the matching transformer to the radio in the DX Room, so the loss at 57 feet with RG6 would be minimal. I have 75 feet of RG11, but I doubt it would be worth the effort. With our high winds, raising the antenna more than 15 feet I am asking for trouble, and getting the 9.2 from Germany, I baby it. hi.
      Living on the Northern OR coast I can regularly get from Vancouver BC to Coos Bay OR, which isn't too bad. My old Windgard 6065 got me down to Eureka CA on Trops. But it has about 1 DB more gain being longer. 9.2 does have good F/B though at 81 inches. Most years E Skip is rare. I used to get a lot of it back in the 1970s.
      Last edited by mwdxer; 07-06-2020, 04:30 AM.

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      • #4
        After experimenting with the Korer 9.2 a bit more, I do find it is very directional for its size. I notice even tilting it up of down a slight amount on the pole, makes a huge difference. I used that FM6 for sometime before getting the Korner 9.2. If this 9.2 is so sensitive, I can only imagine a 15.2 or a 19.3. Those must be really touchy. No practical for me, even if I could one. Living on the Northern Oregon Coast, I regular get signals from Vancouver/Victoria BC, down to Myrtle Point, South of Coos Bay and over to Wenatchee WA.. So the distance at only 15' about ground, at about 250 miles in each direction. If I had more height I am sure it would be better, but with our high winds in the Winter, I would not like to take the chance. But for an antenna that is only 82 inches long, the Korer 9.2 does do very well.

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