[Elecraft] K3 H-Mode Mixer Main & Sub RX plus other mods

[Giancarlo Moda]

Hi Geoff,

thanks for your question. The diplexer that includes an attenuator, does some stabilization for the filters. The Amplifier still changes impedance as Idss current is changing due to HAGC action.

No apology, thanks

Best 73

Gian
I7SWX




>________________________________
> Da: Geoffrey Mackenzie-Kennedy <lx2ao at pt.lu>
>A: Giancarlo Moda <i7swx at yahoo.com> 
>Cc: Elecraft Discussion List <elecraft at mailman.qth.net> 
>Inviato: Lunedì 14 Maggio 2012 22:56
>Oggetto: Re: [Elecraft] K3 H-Mode Mixer Main & Sub RX plus other mods
> 
>Hi Gian,
>
>Did you find that your diplexer termination for the filters also prevented the changing input impedance of HAGC controlled amp Q1 from changing the Group Delay Variations of the filters, especially the narrower filters?
>
>My apology for not replying to your last email, will explain off-list.
>
>73,
>Geoff
>LX2AO
>
>
>
>On May 14, 2012 at 21:57 +0200, Giancarlo Moda wrote:
>
><snip>
>
>
>> Following K3 owners request, a mod relative to a diplexer termination fot the xtal filters bank is available. This is made to reduce filters IMD due to change of impedance of the
>> HAGC Q1 amplifier.
>
>
>
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