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Re: [TowerTalk] who's "right" (a tuner question)

To: "Grant Saviers" <>, "jim feldman" <>, <>
Subject: Re: [TowerTalk] who's "right" (a tuner question)
From: "Gene Fuller" <>
Date: Mon, 6 Dec 2010 14:44:58 -0500
List-post: <">>
I believe that MFJ at least used to sell a fix for that - probably a high 
pass filter.
Gene / W2LU
----- Original Message ----- 
From: "Grant Saviers" <>
To: "jim feldman" <>; <>
Sent: Monday, December 06, 2010 2:18 PM
Subject: Re: [TowerTalk] who's "right" (a tuner question)

> Your MFJ may not be "hosed" because it is sensitive to other frequency
> RF as it energy detects broad-banded.  Mine is unusable on antennas
> because of a 50kw AM band tower about 1 mile away.  OTOH my AIM4170
> handles the same situation with just an small noise blip which easily
> averages out.
> Grant KZ1W
> On 12/6/2010 10:30 AM, jim feldman wrote:
>> The cast of players: Kenwood TS-940, Heath SA 2060 ant. tuner, MFJ 259. 
>> I
>> was trying to use the MFJ to create a table of settings for the tuner. 
>> Just
>> wasn't working (never could find a SWR much lower than say 1.8:1).  After
>> further reading, I tried the noise peaking method with C.out at max, 
>> at
>> about half and I dialed in L from the bottom.  Once I had that (which got 
>> me
>> surprisingly close), I turned the 940 power all the way down (around 
>> 10w),
>> set the output to cw, hit transmit (after a quick ID) and dialed in a 
>> near
>> 1:1 match in any band between 75-15.  The TS-940 SWR readings were pretty
>> close to the meter on the tuner.
>> So who's right and why?  In one corner we have the transmitter and tuner.
>> Close enough I'd consider them the same.  Should I prefer the tuner 
>> reading?
>>   In the other corner, we have the MFJ that wasn't even in the same 
>> ballpark.
>>   Is it hosed?  I had it cabled to the tuner input for testing purposes. 
>> Is
>> it because of the low output of the MFJ?  I swapped around all cables 
>> except
>> the output to the antenna.  Put fresh cells in the MFJ.
>> All connections were either RG8x (foil and braid) or RG213 except LMR400 
>> out
>> to the trapped vertical antenna. Yes, I'm aware of the efficiency issues
>> here, but I'm on a small suburban lot with 35ft height restrictions and a 
>> YL
>> who tolerates (just) my "metal pokey things" in her garden.
>> thanks
>> jim (w6jmf)
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