[Hallicrafters] Weird SX-101A

[Gary H. Harmon, Jr.]

"Making slow progress on the 101.  Life just keeps getting in the way!
However, got 3 wire power cord installed today + new 2KV AC line bypass
caps.  Have run into a strange issue with the always on filament
transformer.  The original transformer was disconnected and left in the
chassis, new Radio Shack transformer installed along with rectifier and
regulator.  Not standard by any means and filament was wired for 6VDC, not
AC.  Strange modification.  Still researching correct configuration which
used a combo AC & DC on the filament of the converter tube.  Specs call for
27VAC on the filament per Hallicrafters which is more than 2x rated filament
voltage from tube manufacturer.  This circuit is nuts!"

 

Any thoughts on what someone was attempting to accomplish?

 

Best 73

 

Gary H. Harmon, Jr. - K5JWK - HAM Radio, HEATHKIT, and ATARI Archaeologist

6003 Archwood

San Antonio, TX 78239-1504

(210) 657-1549 <home>

(210) 884-6926 <cell and text>

(210) 657-1549 <FAX with prior notification>

gharmon at idworld.net

 

"Retirement = Every day is a Saturday except Sunday"

"Real radios glow in the dark"

"Too many projects, not enough time"

 

http://www.grissomroadcoc.org