[ICOM] SWR problem on 706Mk2G

[Tony Hwang]

Hi,
 From simple DC theory based on Ohm's law, In AC(RF) circuit reactive 
component comes in.
Like R+/-jX    This jX(conjugatory number) is reactive component. + is 
inductive, - is capacitive.
You can visualize it in X-Y coordinant and/or polar vector graphs.
If antenna is cut too long for the desired frequency it'll present 
inductive reactive value, if cut too short,
opposite.  You can cut or lengthen the antenna element or cancel the L 
or C reactance applying opposite
reactance. Let's see another example. in a 3 element Yagi, director is 
tuned to to higher frequency(C reactance),
radiator is tuned to desired frequency(only R value), reflector is tuned 
to lower frequency(L reactance)
Antenna noise bridge is very good. Very handy tool for playing ith 
antenna tuning. Sorry jumping in.
Season's greetings to you all.
73,
Tony, VE6CGX


John Geiger wrote:
> Hi Gary,
>
> If it is a reactive component that the 706MKIIG doesn't like, what is the
> best way to handle that?
>
> 73 John AF5CC
>
> On Sat, Dec 19, 2015 at 5:26 PM, Gary Fiber <gfiber at comcast.net> wrote:
>
>> Does the SWR straighten out when you transmit into a dummy load? I always
>> question use of an antenna as a standard test jig even if "Ok" with other
>> rigs. Maybe the PA is spurious on 15 and 6 meters. Maybe some reactive
>> component in the antenna the 706MK II does not like. Icom's were pretty
>> tight for correct SWR specs, some other rigs like Kenwoods don't care and
>> will be happy into almost a 3:1 mismatch, Icoms like 1:5:1 maybe 2:1 at the
>> most.
>>
>> Gary P. Fiber K8IZ
>>
>>
>>
>>> On Dec 19, 2015, at 12:33 PM, John Geiger <af5cc2 at gmail.com> wrote:
>>>
>>> I recently purchased a used ICOM 706MK2G and it seems to have swr meter
>>> issues on a couple of bands.  This occurs on 15 and 6 meters where the
>> swr
>>> is reading higher than what it should.  Has anyone seen this before, or
>>> knows how to fix it?
>>> I tried tightening the circuit board screws and that didn't fix it.
>>>
>>> 73
>>> John AF5CC
>>> ----
>>> Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
>>> Icom Users Net: Sundays, 1700Z, 14.316 MHz
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>> ----
>> Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
>> Icom Users Net: Sundays, 1700Z, 14.316 MHz
>> Icom FAQ: http://www.qsl.net/icom/
>> To support QSL/QTH.net: http://www.qsl.net/donate.html
>>
> ----
> Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
> To support QSL/QTH.net: http://www.qsl.net/donate.html
>