[TenTec] Orion headphone clicks-the fix??

[Gary Tuck <gtuck@mac.com>]

Found this thread from last winter which seems to explain why my 
sidetone sounds so rough if the band noise level is high and I'm 
sending with little or no QSK delay.  I make sure NR is on and QSK 
delay at 10 or higher and then the sidetone sounds smooth.

But what about clicks on the first element when receiving CW if the 
signal is moderate to strong? It is as if the AGC cannot react quite 
fast enough.  If I change the speed to Slow, that helps.  If I 
introduce Hang of .3 seconds or more, that helps too.  Do others notice 
this too?  Is it general behavior as Ulrich describes?

tnx, Gary W7TEA



Bob Henderson <bob@cytanet.com.cy> wrote:
 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

 In fact, this seems somehow plausible to me. It's probably just the 
price one has to pay for the excellent behaviour the ORION was stated 
to have on weak-signal work and an AGC setting optimized therefor. If 
you want to have a receiver which gives a good audio for weak signals 
with not far less audio power then for loud signals, you have to use a 
sufficient high IF amplification and a low AGC threshold. On the other 
hand, the ORION allows a defined setting of the AGC threshold, thus 
making it possible to adopt the behaviour to the band actually in use. 
It makes no sense to have AGC threshold at -130 dBm if your noise level 
is -120 dBm.
 Additionally, if the AGC attac time is not fast enough or the AGC 
reacts not at once when switching back to RX in QSK mode, you'll get an 
"overshooting" AF output until the AGC has attenuated the noise...

I can reproduce the same "problem" (I really never considered it as a 
problem...) on my TS850. At certain speeds and volume levels, I hear 
those clicking noise transients, and if I hang the AGC up to a certain, 
higher value, the clicking disapears. That's just the same.

So, it's really not an ORION problem, it's just a general behaviour..


73,
Ulrich dh0ghu
dh0ghu@dh0ghu.de

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