Remember, a mis matched antenna, a non-resonant antenna at the point where
the feedline connects to the antenna itself, is a poor antenna. An antenna
tuner simply provides you with a better SWR where the feedline connects to
your transmitter. That does not tell you what the actual match is at the
other end of the feedline. You can achieve more improvement in signal
strength, especially, when you consider DB gain per dollar, from a good,
resonant antenna than from an amplifier.
Ron, K8HSY
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Steve Dresser
Sent: Wednesday, January 01, 2014 1:38 PM
To: [log in to unmask]
Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant Frequency
Tom,
If the antenna is that badly compromised, you'll need the external tuner to
get the SWR down to something useable.
Steve
----- Original Message -----
From: "Tom Behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, January 01, 2014 14:03
Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant Frequency
> Kelvin:
>
> Well, rest assured that I absolutely and unequivocally make sure the
> auto-tuner in my TS590 is off when using my amplifier here at the home
> QTH.
> ... That is something that our friend Kevin (K7RX) stressed to me when I
> got
> started into the hole business of using an amplifier, back about 4 or 5
> years ago.
>
> Regarding an MFJ auto-tuner as a possible substitute for the noise bridge
> out in the RV, I had actually thought of that, but didn't think it would
> get
> me that much further ahead, since the TS480 already has a built in auto
> tuner.
>
> My thinking is that the noise bridge might come in handy out at the RV,
> when
> I'm trying to tune a highly-compromise antenna that the TS480's built-in
> auto-tuner won't tune.
>
> I hope this makes sense.
>
> Tom Behler: KB8TYJ
>
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Kelvin Marsh
> Sent: Wednesday, January 01, 2014 1:58 PM
> To: [log in to unmask]
> Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant
> Frequency
>
> Hi Tom,
>
> I was very pleased to see that Bob has already answered the question about
> using two or more ATUs in series. I guess you might get away with it if
> using low power, but the voltages can be extremely high and potentially
> dangerous and damaging. To take it a step further, it is highly
> recommended
> to disable a rig's internal ATU if using an amplifier and external ATU.
> Just in case it is accidentally switched on.
>
> I'll throw another observation into the ring, about using the noise bridge
> in your RV. When I checked the prices here in the UK for the MFJ-212, I
> found I could get an LDG 100 watt auto tuner for not much more money
> <smile>!
>
> Best wishes, Kelvin Marsh - M0AID
>
> Working to improve accessibility for radio amateurs with disabilities
>
> www.active-elements.org
>
> For accessibility evaluations of amateur equipment and MP3 manuals
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Tom Behler
> Sent: 01 January 2014 18:32
> To: [log in to unmask]
> Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant
> Frequency
>
> Lowell:
>
> That's exactly what I'm thinking here if I use the Noise Bridge at the
> home
> QTH.
>
> I'd put the noise bridge between the TS590 and the amplifier.
>
> At the RV, of course, there's no amplifier to go with the TS480, so excess
> power would not be a concern.
>
> Tom Behler: KB8TYJ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Lowell Miller
> Sent: Wednesday, January 01, 2014 11:57 AM
> To: [log in to unmask]
> Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant
> Frequency
>
> Tom, I have my 212 between the TS2000 and the amplifier.
> I would not want to put the 212 in danger with the output of the amp.
> Happy New Year and 73.
> Lowell W8QIY
> ----- Original Message -----
> From: "Tom Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, January 01, 2014 11:25 AM
> Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant
> Frequency
>
>
>> Howard:
>>
>> I guess I get this, but wouldn't you have to put the tuner in the bypass
>> position?
>>
>> I can do this with my Tentech 238A manual tuner in the shack, but the MFJ
>> 901B manual tuner I would use in the RV does not have a bypass position,
>> at
>> least so far as I know.
>>
>> Tom Behler: KB8TYJ
>>
>>
>> -----Original Message-----
>> From: For blind ham radio operators
>> [mailto:[log in to unmask]]
>> On Behalf Of Howard Kaufman
>> Sent: Wednesday, January 01, 2014 11:13 AM
>> To: [log in to unmask]
>> Subject: Re: Using MFJ Noise Bridge To Determine Antenna Resonant
>> Frequency
>>
>> Set the bridge and tune a receiver until the pulses minimum is heard.
>> Kind
>> of looking for a needle in a haystack.
>>
>>
>> ---
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>
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