[ICOM] IC-706mkIIg with TurboTuner

[Steve Lewis]

Dumb question -- why would you ever use a tuner (any sort) in line with 
a Tarheel (any sort)?

J.F. Samuels wrote:
> This problem is still driving me crazy after two years.
> 
>  
> 
> My IC-706 worked fine into the tuner.
> 
>  
> 
> My newer IC-706mkIIg has always exhibited the following weird problem:
> 
>  
> 
> On 15 or 17 meters, only, when I press the antenna tune button, 95 times out
> of 100 the Power Out indicator pegs instead of one or two segments, and the
> antenna will never achieve resonance - it will end in beeps and reset to
> zero.  The SWR meter never shows a dip.  If I remove the TurboTuner and tune
> the antenna (Tarheel 200) manually, the IC-706mkIIg works fine.
> 
>  
> 
> The other five percent of the time the meter shows normal low tuning output
> and I achieve resonance.  But, if I stay on high power and modulate in SSB,
> the meter "sticks" up at max, and the signal at that point is not heard or
> is not modulated.  A power setting of 6 or below sometimes works, but that
> is not an option.
> 
>  
> 
> I finally coupled a frequency meter to the output and found that the signal
> that pegged the output meter and would not achieve resonance appeared to be
> about 13 mHz.  This doesn't make much sense, either, for it should achieve
> resonance at that frequency OK.
> 
>  
> 
> I took a three foot RG-8X jumper and placed RF cores and a big toroid inline
> and put this between the tuner and the antenna.  It has helped, and
> sometimes I can tune OK and work 17 meters, sometimes 21, but not always.
> Despite trying all sorts of combinations of cable lengths, placement and RF
> decoupling, I cannot improve the situation.  Sometimes it is OK until I get
> close to resonance while tuning, then jumps up.
> 
>  
> 
> It almost appears that the tuner is not presenting a 50 ohm load to the
> output of the ICOM, perhaps something higher, and the de-loading
> causes/allows a spurious oscillation in the output of the ICOM.
> 
>  
> 
> Does anyone have any suggestions?  I have also sent this query to Bill,
> N2VZ, manufacturer of the TurboTuner.
> 
>  
> 
> Stumped,
> 
>  
> 
> 73, John, K2CIB (since 1952)
> 
>  
> 
> ----
> 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/
> 
>