Hallicrafters S38B
 

Picked up an S38B to relive my childhood and it seems to work on AM
about as well as my only other receiver, TS430.

I am going to make it my AM station receiver if and when I can get the
BFO to work. I still need the Kenwood to know where the Ranger is at.

I tried moving the E wire around as suggested in the manual but it did
not help. No heterodyne at all.

Anyone with any experience with this?

JACK K9ACT

--
PHOTO OF THE WEEK: http://schmidling.com/pow.htm
Astronomy, Beer, Cheese, Fiber,Gems, Sausage,Silver http://schmidling.com

Hallicrafters S38B
 

"Jack Schmidling" wrote in message
...
Picked up an S38B to relive my childhood and it seems to work on AM about
as well as my only other receiver, TS430.

I am going to make it my AM station receiver if and when I can get the BFO
to work. I still need the Kenwood to know where the Ranger is at.

I tried moving the E wire around as suggested in the manual but it did not
help. No heterodyne at all.

Anyone with any experience with this?

JACK K9ACT


Brian Ripley, K8BR of Ogden, Utah has a great site devoted to the care and
restoration of the Hallicrafters S-38 series.
http://www.the-s38-guy.com/

Your BFO question
http://www.the-s38-guy.com/Page_63.html

Back cover S38 series reproductions are available from
Bob's Antique Radio & Electronics - LaGrange Park, IL
http://www.radioantiques.com/mall.html

Hallicrafters S38B
 

Jack Schmidling wrote:

Picked up an S38B to relive my childhood and it seems to work on AM
about as well as my only other receiver, TS430.

I am going to make it my AM station receiver if and when I can get the
BFO to work.

Just for fun, try a kludge BFO. Place an AM broadcast band radio (non-digital)
as physically close to the S38 as you can get it. Tune the broadcast band radio
until you hear a beat with the AM or CW signal you are listening to on the S38.
The oscillator in the AM radio should leak into the S38 to cause the beat.
Course it depends on somewhat poor shielding on both receivers to work. I
sometimes used this method as a kid to listen to SSB and CW on those old SW
receivers that didn't have a BFO. Those were the days... ;)

Hallicrafters S38B
 

AaronJ wrote:

Just for fun, try a kludge BFO. Place an AM broadcast band radio (non-digital)
as physically close to the S38 as you can get it. Tune the broadcast band radio
until you hear a beat with the AM or CW signal you are listening to on the S38.

Actually, I already did that but it's a pretty academic exercise.

After all is said, seems like there should be some way to control the
feedback to both provide a beat and optimize the gain/selectivity.

I have no interest in CW or sideband with this radio but I do need some
way to set my ranger on the station I am listening to.

Any thoughts on an outboard tweak?

js

--
PHOTO OF THE WEEK: http://schmidling.com/pow.htm
Astronomy, Beer, Cheese, Fiber,Gems, Sausage,Silver http://schmidling.com

Hallicrafters S38B
 

Jack Schmidling ) writes:
AaronJ wrote:

Just for fun, try a kludge BFO. Place an AM broadcast band radio (non-digital)
as physically close to the S38 as you can get it. Tune the broadcast band radio
until you hear a beat with the AM or CW signal you are listening to on the S38.

Actually, I already did that but it's a pretty academic exercise.

After all is said, seems like there should be some way to control the
feedback to both provide a beat and optimize the gain/selectivity.

There's no control for it? That seems odd.

The trick is to make the cathode resistor variable, and use that to
control the level of regeneration.

I have no interest in CW or sideband with this radio but I do need some
way to set my ranger on the station I am listening to.

Any thoughts on an outboard tweak?

js

Don't put it on transmit, but key the oscillator? Old rigs often
were set up that way, so you'd have a weak signal from the transmitter
to set the receiver to.

Or, they'd have some spotting function specifically for it.

Michael VE2BVW

Hallicrafters S38B
 

The simplest way I can think of is to go over to the shelf of test equipment
and grab the old Heath signal generator and attach a foot long wire close to
the S-38. Then tune the generator to 455 kc (whoops, that is kHz). You
will have a nice beat note.

Like the others have said, convert the if stage into an oscillator - then
reduce the feedback to get it to stop oscillating. That will then be sort
of a Q multiplier while in the feedback but not enough to oscillate stage.
You would need a control to put in and out of oscillation. A pot, a
variable capacitor or a switch.

Or, just a hum a few bars into the Ranger mike and tune for best audio.

73, Colin