TenTec
[Top] [All Lists]

[TenTec] Omni V buzz on 14 mHz

To: tentec@contesting.com
Subject: [TenTec] Omni V buzz on 14 mHz
From: "Gary Smith" <Gary@doctorgary.net>
Reply-to: Gary@doctorgary.net,Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Sat, 15 Dec 2007 11:06:08 -0500
List-post: <mailto:tentec@contesting.com>
I'm buzzing... Well, the Omni V is anyway.

My Dad had this Omni V and there was an intermittent sound it would 
make that he couldn't ID its cause. When he sent it back to TenTec 
they did all the factory mods but the sound didn't show up while it 
was there. He mothballed it and now I've got the radio.

After first using it (a month ago) I did hear what is likely to be 
the same sound he was hearing, I called TenTec to see what they 
thought and I was suggested to reset it. Doing so did stop the noise 
and I began using/learning about the radio. It came back again and 
I'd ordered N4PY's V.92 chip and hoped among the other things it 
exorcises, it might fix the noise issue as well. Alas, no such luck.

I've been using it exclusively and with no difficulties on 40 & 80 
meters. With the exception of background internal noise of what are 
possibly as mentioned here from old leaky caps, the radio has been 
exceptional on receive and I thought a solder joint I secured which 
fixed the display might have been the solution. Not so.

I finally put it on 20 meters & after 20 minutes or so this noise 
started again. I went back to 40 meters and the receive was normal. 
Aha! so I let it sit on the other bands and they are fine too; it's 
only on 20M that the radio generates this noise. 

To describe the sound, it is like the old "Fuzz" sound from a 60's 
rock group. It is overpowering in volume but is not reflected on the 
S meter. I can still hear stronger cw in the background but the tones 
are not pure, they consist of buzzes at different pitches. 

On my old corsair when I would turn the noise blanker all the way up 
in the presence of line noise it would have much the same character 
to the CW signals; I would hear them as if it were an old spark gap 
kind of character. Speaking of the noise blanker & the similarity to 
the corsair noise as just described, the noise blanker in this radio 
does not seem to work. If I turn the control clockwise nothing 
happens for 90% of the travel and there is a narrow area of effect 
and then at the last 4-5% of clockwise travel it completely cuts off 
any sound and the S meter goes dead. I did check the adjustment and 
it is indeed working, varying the voltage from around 5v to zero.

Back to the character of the  sound I'm asking about; the sound varys 
but does so by immediate change in pitch, no gradual shift. It is a 
wall of sound constant and only the pitch changes. 

When I switch to a different band the problem again goes away but if 
I immediately go back to 20, the sound is gone. It invariably returns 
but there's no telling when that will be. It's a workable workaround 
but sometimes the sound returns within moments & sometimes it's OK 
for a long time.

I haven't gone into the lower part of the radio but did open the top 
to see if I could cause any change in the sound by jarring any boards 
& components, and I could not make any change. Only resetting the 
radio or changing bands stops it.

Any ideas where I might look & try to do as it's only in the 20 
meters setting that the little gem of a noise happens? 

Thanks,

Gary
KA1J
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec

<Prev in Thread] Current Thread [Next in Thread>