From:[email protected] [mailto:[email protected]] On Behalf Of Maynard Wright via groups.io Sent: Thursday, February 27, 2025 3:38 PM To:[email protected] Subject: Re: [HallicraftersRadios] S-85: how are the RF amplifier tube (v1) and the MIX/OSC tube (v2) coupled in band1?
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Hi, Don,
When I said that there is no C62 equivalent in the S-40A, I meant that there is no capacitor like C62 that is connected around the switching and resonant circuits so that it is completely independent of the setting of the bandswitch.
73,
Maynard W6PAP
On 2/27/25 11:49, don Root wrote:
Maynard on the S-40A,? C62 is ??in use on band 2 only but connects V1 and V2?? like in the B version …I think.
We need somebody to LRC a sample switch.
*From:*[email protected] [mailto:[email protected]] *On Behalf Of *Maynard Wright via groups.io *Sent:* Thursday, February 27, 2025 11:16 AM *To:* [email protected] *Subject:* Re: [HallicraftersRadios] S-85: how are the RF amplifier tube (v1) and the MIX/OSC tube (v2) coupled in band1?
Note that the S-40A uses an entirely different arrangement of coils and capacitors and has no equivalent to C62 in the S-40B.
So why is the S-40B equipped with C62? Maybe switch S1B in the S-85 exhibits a higher capacitance between the two rotary segments than does S1B in the S-40B, making C62 unnecessary to achieve the desired coupling capacitance in the S-85.
Although the parts numbers are the same, maybe Hallicrafters used a different switch vendor for the S-85.
Knowing this would matter only if someone were restoring a receiver and expected a part number for one type to represent the same exact part for another type. And maybe that's the case. But I haven't thought about that until now.