Warning: Creating default object from empty value in /homepages/11/d132647312/htdocs/Amfone/mkportal/include/SMF/smf_out.php on line 47
panoramoscope to sx-28




 
The AM Forum
October 20, 2019, 08:07:03 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: panoramoscope to sx-28  (Read 5457 times)
0 Members and 1 Guest are viewing this topic.
xe1yzy
Member

Offline Offline

Posts: 344


« on: April 27, 2006, 11:52:36 AM »

Hello Guys,

Well , I found a Nice Panoramascope SA3, and I planning to connect this scope to my Hallicrafters SX-28, (  a really nice match) , so,I need to connect the panoramic adaptor to the plate of the first detector in the SX28 trough a "bloking resistor".

In your opinion, what should be the value of this Blocking resistor, to have the maximun acuracy?

Input frecuency: 455 Khz
Max. Sweepwidht: 200 Khz

My very best regards to all

Pedro XE1YZY.

Logged

TVI WHAT TVI?
Pete, WA2CWA
Moderator
Member

Offline Offline

Posts: 7690


CQ CQ CONTEST


WWW
« Reply #1 on: April 27, 2006, 12:25:47 PM »

If you're going to use it as a panoramic adapter( to view the spectrum) the connection should be made before the 1st amplifier(normally to the plate of the converter tube through a resistor), not at the detector stage.
Logged

Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
xe1yzy
Member

Offline Offline

Posts: 344


« Reply #2 on: April 27, 2006, 01:05:38 PM »

If you're going to use it as a panoramic adapter( to view the spectrum) the connection should be made before the 1st amplifier(normally to the plate of the converter tube through a resistor), not at the detector stage.

Hi Pete

Well, the Manual of panoramic scope says first detector, this scope is a complete superheterridyne receiver which is periodically tuned over the fixed band of the frecuency spectrum, centered at the intermediate frecuency of the companion receiver (SX-28), but shure ,I can also try the mixer, but the value of the isolation resitor is the doubt.

Regards!
Logged

TVI WHAT TVI?
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4590



« Reply #3 on: April 27, 2006, 01:06:40 PM »

First detector = converter = mixer.  Second detector is the IF to audio detector.

Pedro, my ARR-7 uses a 100K or so resistor on the plate of the first detector for the panadapter output.  The ARR-7 is roughly equivalent to the SX-28.

The reason for this is so the detector (converter) isn't loaded down by the panadapter.

73 John
Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
xe1yzy
Member

Offline Offline

Posts: 344


« Reply #4 on: April 27, 2006, 01:20:45 PM »

First detector = converter = mixer.  Second detector is the IF to audio detector.

Pedro, my ARR-7 uses a 100K or so resistor on the plate of the first detector for the panadapter output.  The ARR-7 is roughly equivalent to the SX-28.

The reason for this is so the detector (converter) isn't loaded down by the panadapter.

73 John

Hey Johny!

Nice to "read" you again, thanks for your help, tell me something more please, what should be the right shielded connecting cable?, or just a small lenght coaxial cable works ok?

un abrazo!

73 Pedro
Logged

TVI WHAT TVI?
Pete, WA2CWA
Moderator
Member

Offline Offline

Posts: 7690


CQ CQ CONTEST


WWW
« Reply #5 on: April 27, 2006, 07:42:35 PM »

John said: First detector = converter = mixer.

For some reason, calling the converter or mixer the "first detector" doesn'r ring any bells for me. Can't recall ever calling them a detector.
Anyway Pedeo, I think you got the picture where the panadapter should be connected. With my Panoramic PCA-2, T-200 Panadapter, connected to my National NC-183D, I also used a 100K resistor to the "mixer" plate. A short run of RG-58U coax, about 18 inches, was used to make the connection.
Logged

Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4590



« Reply #6 on: April 27, 2006, 08:33:40 PM »

Hola, Pedro, como te va?  Any shielded cable would probably do OK - RG-58 or RG-59, the shorter the better OM!

Pete - Look in any old Riders manual.  "Frist Detector" was a common usage until the late thirties or so and continued for a while thereafter.  See this one for example: http://www.nostalgiaair.org/PagesByModel/209/M0013209.pdf

73 John


Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
Pete, WA2CWA
Moderator
Member

Offline Offline

Posts: 7690


CQ CQ CONTEST


WWW
« Reply #7 on: April 27, 2006, 08:59:38 PM »

Hola, Pedro, como te va?  Any shielded cable would probably do OK - RG-58 or RG-59, the shorter the better OM!

Pete - Look in any old Riders manual.  "Frist Detector" was a common usage until the late thirties or so and continued for a while thereafter.  See this one for example: http://www.nostalgiaair.org/PagesByModel/209/M0013209.pdf

73 John

Probably why I didn’t recognize it since I generally don’t dabble with radios that era.
Logged

Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
w3jn
Johnny Novice
Administrator
Member

Offline Offline

Posts: 4590



« Reply #8 on: April 28, 2006, 08:16:57 AM »

Sheez, Pete, yer an older buzzard than I am... and you have all a them thar manuals to boot  Grin
Logged

FCC:  "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
Pete, WA2CWA
Moderator
Member

Offline Offline

Posts: 7690


CQ CQ CONTEST


WWW
« Reply #9 on: April 28, 2006, 01:27:22 PM »

Sheez, Pete, yer an older buzzard than I am... and you have all a them thar manuals to boot.

But I'm moving the other way along the technology line.  "Old" doesn't excite me anymore. And, even with all these manuals, I just review them for completeness (all pages as defined) and readability but not for technical or verbal accuracy. I just did a Hammarlund for HQ-120 manual for a customer and they used the “converter” nomenclature.
Logged

Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
The Slab Bacon
Member

Offline Offline

Posts: 3934



« Reply #10 on: April 28, 2006, 02:07:05 PM »

In the early days of superheterodyne receivers the "converter" was always refered to as the "first detector". This nomenclature stayed in place for many years. In those days the audio detector was then called the second detector. I have become so used to that terminology that it automatically clicks in my brain. I will usually always say converter or mixer, however if I hear "first detector" my brain automatically translates it inside.

However, the term "converter" usually refers to a self oscilating mixer stage, where
"mixer" usually confers that there is a seperate local oscilator.  Just my $.02 worth.

                                                                         The Slab Bacon
Logged

"No is not an answer and failure is not an option!"
xe1yzy
Member

Offline Offline

Posts: 344


« Reply #11 on: April 30, 2006, 01:13:51 PM »

Ok, well, thanks guys, finally the panoramascope are working, and also I learn something about an Old mixers, converters and oscilators, Is usefull for me because, we deal with old radios , but with old books too!

You are a great Guys Thanks!

Pedro XE1YZY
Logged

TVI WHAT TVI?
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.039 seconds with 18 queries.