Notices
JR Radio & Spektrum Radios Discuss all your JR and Spektrum gear.

JR RX XTAL Markings

Old 06-28-2003, 02:20 PM
  #1  
lowpasstwo
Thread Starter
My Feedback: (127)
 
lowpasstwo's Avatar
 
Join Date: Jan 2002
Location: Springtown, Texas
Posts: 57
Likes: 0
Received 0 Likes on 0 Posts
Default JR RX XTAL Markings

Danny:

The JR "grey cap" FM receiver xtals have "three small circles" on the label with one typically "filled" in.

What does this indicate? Does this affect interchangeability or
compatibility receiver to receiver?

thanks,

Terry
Old 06-30-2003, 01:26 PM
  #2  
dsnyder
 
dsnyder's Avatar
 
Join Date: Jun 2002
Location: Champaign, IL
Posts: 9,365
Likes: 0
Received 1 Like on 1 Post
Default JR RX XTAL Markings

The dots indicate where the crystal is cut in relationship to the frequency listed. It is general policy to avoid having opposite dots, that meaning to not have the transmitter crystal with a dot on the left and the receiver crystal from having a dot on the right. With todays level of tuning however it makes very little difference in performance.
Old 06-30-2003, 06:01 PM
  #3  
sfaust
My Feedback: (11)
 
sfaust's Avatar
 
Join Date: Sep 2002
Location: Boston, MA
Posts: 1,902
Likes: 0
Received 0 Likes on 0 Posts
Default JR RX XTAL Markings

What does it indicate in terms of shift. For example, how far off are two crystals if one dot is on the right, and the other crystal has a dot off on the left? Basically, what is the resolution that the dots signify?

Thanks
Old 06-30-2003, 06:12 PM
  #4  
dsnyder
 
dsnyder's Avatar
 
Join Date: Jun 2002
Location: Champaign, IL
Posts: 9,365
Likes: 0
Received 1 Like on 1 Post
Default JR RX XTAL Markings

It has to do with the crystal cut being slightly to the right or to the left of the exact frequency when viewed on a scope. The difference is very minor in the amount of deviation, but it is a way the JR allows users to have the best possible link for extreme conditions and applications. Today it makes very little difference.
Old 06-30-2003, 08:44 PM
  #5  
sfaust
My Feedback: (11)
 
sfaust's Avatar
 
Join Date: Sep 2002
Location: Boston, MA
Posts: 1,902
Likes: 0
Received 0 Likes on 0 Posts
Default JR RX XTAL Markings

I realized that it had to do with the cut being off just a little. I was wondering more if you know what off a little meant in terms of a number. Its easier to compare the differences if a number is specificed, rather than something less descriptive as 'just a little'

Do you know how far off a crystal needs to be off center before it gets the left or right dot? If not, could you ask around? Thanks.
Old 07-01-2003, 12:40 PM
  #6  
dsnyder
 
dsnyder's Avatar
 
Join Date: Jun 2002
Location: Champaign, IL
Posts: 9,365
Likes: 0
Received 1 Like on 1 Post
Default JR RX XTAL Markings

I don't have specific numbers that I can provide.
Old 07-03-2003, 03:22 AM
  #7  
sfaust
My Feedback: (11)
 
sfaust's Avatar
 
Join Date: Sep 2002
Location: Boston, MA
Posts: 1,902
Likes: 0
Received 0 Likes on 0 Posts
Default JR RX XTAL Markings


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.