[R-390] R-390 RF Gain Control

[Renee K6FSB]

seems like one needs a 50K lin pot and a 6K fixed .. IIRC
Renée K6FSB

On 9/12/21 2:26 PM, David Wise wrote:
> I seem to recall that a fixed resistor from linear wiper to one end can approximate a log taper, probably well enough for this application.
>
> Dave Wise
>
> From: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net] On Behalf Of Roy Morgan
> Sent: Sunday, September 12, 2021 8:08 AM
> To: Kevin Schuchmann
> Cc: R-390 at mailman.qth.net
> Subject: Re: [R-390] R-390 RF Gain Control
>
> To the creative among us,
>
> Some clever person among us likely can design a replacement circuit to function well as the hard to find reverse log taper original gain pots.
>
> Maybe a pot with the right resistance curve but lower dissipation rating combined with a FET or opto-isolator.
>
> Roy Morgan
> Custodian of more than one R-39x radio.
> K1LKY Western Mass
>
>> On Sep 12, 2021, at 1:11 AM, Kevin Schuchmann via R-390 <r-390 at mailman.qth.net> wrote:
>>
>> Hi All,
>>
>> Hunting around I found this on Ebay and I have ordered one. https://www.ebay.com/itm/164923700436<https://www.ebay.com/itm/164923700436>
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