¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
  1. HallicraftersRadios
  2. Messages
Single Messages Topics Expanded

Re: SX-28A Hum

 
Edited

¿ªÔÆÌåÓý

Richard ,agree again

Re ¡°I am pretty sure the markings on the schematic are reversed.???? ??Agree again
It seems to me the Bass switch also changes the gain of the stage by
increasing the B+.¡±??? perhaps if the choke resistance is high?

¡­in the ?Halli ¡°OUT¡± position, at mid frequencies, won¡¯t the choke resistance determine the gain? ?

?

After a gazillion hours, here is ?how Don sees the base boost switch. ?.. comments?

Image here

End image and all

From: [email protected] [mailto:[email protected]] On Behalf Of Richard Knoppow via groups.io
Sent: Sunday, February 16, 2025 5:31 AM
To: [email protected]
Subject: Re: [HallicraftersRadios] SX-28A Hum

?

The B+ goes to the plate of the first audio through R-37, when the
Bass switch is in the IN position (as shown on the schematic) the choke
is bypassed, the B+ to the plate through R-37, when the switch is in the
OUT position, as shown on the diagram R-37 is bypassed and the B+ now
from R-38 goes to the choke and thence to the plate. So, in one position
the plate load is R-37 and in the other position its the choke and
condenser. I am pretty sure the markings on the schematic are reversed.
It seems to me the Bass switch also changes the gain of the stage by
increasing the B+. If I am seeing it right either R-37 or the resonant
choke is put out of the circuit by the Bass switch. It is 2:30AM and I
have no business being on line. ?


--
don??? va3drl
Join [email protected] to automatically receive all group messages.