[Elecraft] Turning off Amp PTT when using Tune Button

[Richard Thorne]

Thanks Howard:

Excellent information, you know what I'm trying to accomplish.

I'm aware of those tuners and thats why I thought it may be nice to have 
the ptt automatically disabled within the rig.  There are less expensive 
high power tuners that don't have the features the SG-500 or Palstar 
has. MFJ has one also and is the least expensive of the 3.  Any tuner I 
would use would be installed at the base of the tuner and would need to 
be protected from the wx.

Rich - N5ZC

HowardZ wrote:
> When you buy the SG-500 amp, be sure to also buy the "remote on/off switch".
> This remote is also your BAND SELECT switch which also has an AUTO settings.
> If SGC would post a picture and description of it, I am sure they'd sell
> more of them.
> Considering the work it took to design and build it, I think the switch is
> worth the money.
> The best price is probably at R&L electronics.
>
> Now, you know, sooner or later you are going to forget to switch the
> amplifier off before tuning.
> Your auto-tuner will then fry when trying to tune with 500 to 700 watts
> going through it.
> (Yes the SGC 500 can develop over 700 watts - depending on the band in use)
> The Palstar AT-AUTO tuner has a PTT input and PTT output - it keeps the
> amplifier off both when tuning and also whenever the SWR is below the
> threshhold you designate (typically somewhere between 1.5 and 2.0).  The
> Palstar is also rated for 1500 watts - any mode.  It's expensive, but it
> gets you a perfect SWR - unless your antenna really can't do it.  All the
> relay operated auto tuners are a compromise - they are not capable of
> adding/removing small enough amounts of inductance or capacitance for a
> truely perfect tune - though the relay auto tuners can be lightning fast.
>
> I think all the amps have self protection from high SWR.
> You should have some kind of PTT automatic cutoff to protect the tuner from
> high SWR while tuning.
> I think only Palstar and SGC auto tuners have this protection feature.
>
> Howard
>
>
> Richard Thorne wrote:
>   
>> Kent et All:
>>
>> Yes thats the easy and simple way.
>>
>> What I was hoping for was quick band changes without the need for 
>> flipping switches.  I'll be running an SG-500 amp and already planned on 
>> placing a switch in the ptt line to disable the amp.
>>
>> Rich - N5ZC
>>
>> K9ZTV wrote:
>>     
>>> Rich . . .
>>>
>>> Can't comment about other amps, but running the K3 barefoot (or tuning 
>>> an external ATU) with the Yaesu Quadra merely requires toggling the 
>>> Quadra's OPERATE switch off.  Toggle it back on to use the amp.
>>>
>>> 73,
>>>
>>> Kent  K9ZTV
>>>
>>>
>>> Richard Thorne wrote:
>>>       
>>>> Is there a way to turn off the ptt signal to an amp when the TUNE button 
>>>> is pushed?
>>>>
>>>> I want to run high power but I want to disable the amp while tuning an 
>>>> external antenna tuner. 
>>>>         
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