RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog

Go Back   The Forums > Amateur Radio > Amateur Radio Equipment

Amateur Radio Equipment - For general and technical discussion of Amateur Radio equipment such as transceivers, repeaters, controllers and receivers.

LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 04-14-2017, 8:32 PM
Join Date: Feb 2017
Location: Winters, CA
Posts: 12
Default S-meter acting funny

I have a Kenwood TS-430S HF tranceiver. When I got it the S-meter wasn't functioning at all. When I looked inside I saw a broken pot (VR3) on the IF board. I looked it up in the service manual and sure enough it was the S-meter adjustment pot. After replacing it, the S-meter functions, but when I turn down the rf gain, the needle goes to increases instead of decreases and shows +60 when the RF gain is down all the way. What could be the issue here? Any help is appreciated.
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 04-14-2017, 8:45 PM
K9DAK's Avatar
  Shack Photos
Shack photos
Audio Feed Provider
Audio Feed Provider
Amateur Radio Operator
Amateur Radio
Join Date: Dec 2010
Location: Wauconda, IL
Posts: 353

That sounds like normal behavior in my experience with my Yaesu FT-847. I believe it's supposed to indicate where your minimum received signal threshold is. So as you described... if you turn the RF gain all the way down and your S-meter indicates +60, you'll only receive a signal that strong or greater.

Hope that helps (and my meager explanation is correct)!
Cheers and 73 de Dave, K9DAK
PRO-51, PRO-92, PRO-106, PRO-197, TRX-1, HTX-202, FT-530, TH-F6A, FT-8000, FT-847

Don't worry, relax, have a homebrew...
Reply With Quote
  #3 (permalink)  
Old 04-14-2017, 10:28 PM
robertmac's Avatar
  Premium Subscriber
Premium Subscriber
Join Date: Jun 2005
Posts: 2,071

If you RTFM it should explain it there. Mine does for the FT-450.
Reply With Quote
  #4 (permalink)  
Old 04-14-2017, 11:40 PM
majoco's Avatar
  Shack Photos
Shack photos
Join Date: Dec 2008
Location: New Zealand
Posts: 2,817

That's quite normal. The "S" meter indicates the voltage on the AGC line. If there is no signal and the RF gain is up full, then the AGC line has no voltage on it and the "S" meter reads zero.With a strong signal, an AGC voltage is developed to reduce the gain and keep the audio level constant - as there is now an AGC voltage, the "S" meter reads something. So now if you turn the RF gain down, nothing happens to the AGC voltage or the strength of the signal until you reach the point where the RF gain starts to reduce the signal level and the "S" meter rises even more - and if you continue then the AGC voltage induced by the RF gain control completely kills the signal and the "S" meter reads S10 +60dB or something.
Cheers - Martin ZL2MC - Palmerston North
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -5. The time now is 3:20 PM.

Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
All information here is Copyright 2012 by LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2015 by LLC Privacy Policy  |  Terms and Conditions