[Boatanchors] Erratum RE: Using a SG-230 tuner on AM

[D C *Mac* Macdonald]

I should have expressed that as 2V time 2I,
not the way I typed it.
 
In the words of Agent 96, Maxwell Smart,
"Sorry about that, chief!"
 
 
73 - Mac, K2GKK/5
Oklahoma City, OK




----------------------------------------
> From: k2gkk at hotmail.com
> To: km1h at jeremy.mv.com; boatanchors at mailman.qth.net
> Date: Sun, 9 Aug 2009 15:01:51 -0500
> Subject: Re: [Boatanchors] Using a SG-230 tuner on AM
>
>
> At 100% modulation peak, the instantaneous voltage
> AND current are both double the static values.
>
> V^2 times I^2 gives you four times the static power.
>
> Current FCC rules allow for 1.5 kW output power.
> That is why the old kilowatt rigs such as Collins
> KW-1 and Johnson Desk Kilowatt can now only be run
> at 375 Watts carrier power.
>
> 73 - Mac, K2GKK/5
> Oklahoma City, OK
>
>
>
> ----------------------------------------
>> From: km1h at jeremy.mv.com
>> To: k2gkk at hotmail.com; boatanchors at mailman.qth.net
>> Subject: Re: [Boatanchors] Using a SG-230 tuner on AM
>> Date: Sun, 9 Aug 2009 15:55:55 -0400
>>
>> Its rated at 200W PEP.
>>
>> However I still have a hard time understanding how you get 4X PEP on AM.
>>
>> For 100% modulation it requires 50% of the RF plate input power. So thats
>> 50W of audio on a 100W input final. At 70% efficiency thats 70W carrier and
>> 50W of total audio using a rather conventional 1:1 modulation transformer
>> ratio.
>>
>> For a Viking I at 100W out that is 140W input which requires 70W audio. That
>> comes out at 170W PEP in my book.
>>
>> Carl
>> KM1H
>>
>>
>> ----- Original Message -----
>> From: "D C *Mac* Macdonald"
>> To: "KM1H Carl Huether" ;
>> Sent: Sunday, August 09, 2009 3:26 PM
>> Subject: RE: [Boatanchors] Using a SG-230 tuner on AM
>>
>>
>>
>> Carl and otherson the boatanchors list:
>>
>> I believe the SGC-230 is rated at 125 Watts PEP.
>>
>> Since the Viking, DX-100, 32V-*, B&W, etc. ran
>> close to 120 Watts carrier, 100% modulation would
>> cause PEP output to be 400-500 Watts.
>>
>> I don't believe it advisable to risk running that
>> sort of power into the SGC.
>>
>> I'm pretty sure most list members are aware of that
>> fact but I believe that it bears refreshing.
>>
>> 73 - Mac, K2GKK/5
>> Oklahoma City, OK
>>
>>
>> ----------------------------------------
>>> From: km1h at jeremy.mv.com
>>> To: boatanchors at mailman.qth.net
>>> Date: Sun, 9 Aug 2009 14:30:11 -0400
>>> Subject: [Boatanchors] Using a SG-230 tuner on AM
>>>
>>> Has anyone tried running a 100W output AM rig thru one of these?
>>>
>>> Id like to be able to be able to run a Viking I or II thru one using a 160
>>> and 75M dipole in parallel for 160-20M.
>>>
>>> Carl
>>> KM1H
>>>=
>>
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