[TenTec] ORION headphone clicks - the fix!

[Mark Erbaugh]

I don't know if this has any bearing, but I had an Omni V which had a noise
problem during T/R switching. There was a recommended fix to add a
capacitor.

Mark
----- Original Message ----- 
From: "Bob Henderson" <bob at cytanet.com.cy>
To: <tentec at contesting.com>
Sent: Monday, December 29, 2003 9:14 AM
Subject: Re: [TenTec] ORION headphone clicks - the fix!


>
> I have been experimenting a little further concerning the clicks I
> noticed in my phones.  As I mentioned in a previous post, the clicks I
> hear are always present on the leading edge transition of the first
> character element sent.  Also, at speeds below about 25 wpm I hear a
> click on the leading edge transition of all character elements.  That
> is, except for yesterday, when regardless of the speed at which I was
> sending I heard absolutely no clicks and the sidetone was sweet and
> clear.  Now today, I am experiencing clicks again at speeds below about
> 25 wpm.
>
> What is going on here?  Well what is going on is that the band noise
> level is changing.  When the band noise is very low, I hear no clicks
> but as the band noise increases the clicks become evident.  This appears
> consistent with K4IA findings.  The click appears to be produced as a
> result of the presence of band noise during T/R switching.  If I connect
> the Orion to a dummy load there are  no clicks evident at any sending
> speed and regardless how long I send.
>
> So why is the problem accentuated at speeds below 25 wpm?  Well, I'm not
> quite sure but it seems to me there has to be something different in T/R
> sequencing above 25 wpm to that below that speed.  I'm guessing, maybe
> above 25 wpm the receiver doesn't become fully unmuted between character
> elements.  As I say, I'm guessing!
>
> On a noisy band with the clicks in evidence I've had a lot of success in
> reducing the clicks and sometimes removing them completely by increasing
> AGC threshold, which I guess prevents the AGC system from trying to ramp
> the noise up to full output between character elements
>
> All very interesting to me.  Hence I offer my observations for whatever
> you consider they're worth.  In the light of some recent postings, I
> have visions of hundreds  of you rushing to cancel your reflector
> subscription! :-D
>
> 73
>
> Bob, 5B4AGN, P3F
>
> K4IA at aol.com wrote:
>
> >I have been doing some more experimenting based on Bob's suggestion to
> >increase the speed.  The clicks went away at about 40 wpm.  A little
speedy for me.
> >I usually send around 25 wpm and increase the spacing to make it
comfortable
> >for the other guy.
> >
> >Then I realized what I was hearing was not a click but the background
> >receiver audio coming up when the QSK shifted over to receive.  Yes, it
happens that
> >quickly.
> >
> >I increased the QSK hang time to 20% so the rig doesn't switch over
between
> >dits and it sounded better.  I only got the click between letters.
Switching
> >to 40% I only get the noise between words and it sounds less like clicks
and
> >more like it really is.
> >
> >I believe this is "the fix for clix."
> >
> >Radio k4ia
> >Craig "Buck"
> >Fredericksburg, Virginia USA
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> >
> >
> >
>
>
>
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