The data I provided is from the Tentec alignment procedure for the two
radios.
The carrier is not in the middle of the passband of the filter, otherwise if
so, one would have a DSB signal not a SSB signal Thus to swap sidebands,
the BFO frequency must change to the opposite side of the filter and is
placed down the slope some 3 dB to 6 dB.
Carrier frequency + / - the modulated audio frequency produces two
sidebands, one of which is eliminated by the filter.
73
Bob, K4TAX
----- Original Message -----
From: "Barry N1EU" <barry.n1eu@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, September 30, 2013 11:58 AM
Subject: Re: [TenTec] TenTec Paragon II model 586,
Maybe my math is wrong, but I figure a passband of 100 Hz to 2900 Hz
with the 2.8 KHz filter with its center frequency of 9001.5 KHz.
Yes, the carrier suppression/null alignment should be carefully
performed after installing the new filter, but it's not a difficult
procedure. I would follow that with on-air tests to verify inaudible
carrier levels.
73, Barry N1EU
On Mon, Sep 30, 2013 at 4:37 PM, Bob McGraw - K4TAX <RMcGraw@blomand.net>
wrote:
The carrier oscillators are not centered in the filter but are typically
at
the edge or somewhat down the slope of the filter edge. And usually down
the slope some 3 dB to 6 dB with the oscillators being switched in
frequency
to the upper edge or lower edge of the filter depending on mode.
In the case of the Omni VI Plus the oscillators switch to produce LSB and
USB signals with oscillator frequency being 9.000000 MHz for LSB and
9.003000 for USB and CW transmit/Tune being 9.000400 MHz. Thus the
filters
are some 600 Hz down the slope of the filter.
With the Paragon the oscillator frequencies are 9.000000 for USB and
9.003000 MHz for LSB and RTTY and 9.000700 MHz for CW/Tune mode.
I don't see much if anything to be gained by changing the transmit
bandwidth
from 2.4 KHz to 2.8 KHz. Thus the audio frequency response would be
about
300 Hz to 2700 Hz with the 2.4 KHz filter and 300 Hz to 3100 Hz with the
2.8
KHz filter.
Another factor to be considered is the carrier suppression as the carrier
is
positioned on the slope of the filter. If the filter response is not
correct, the shape factor not correct and the slope of the filter not
correct, be assured that carrier suppression will likely suffer as the
filter does contribute to overall carrier suppression.
My take on changing filters..........nice science project.
73
Bob, K4TAX
----- Original Message ----- From: "Mike Bryce" <prosolar@sssnet.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Monday, September 30, 2013 10:32 AM
Subject: Re: [TenTec] TenTec Paragon II model 586,
bill,
the same filter is used for BOTH transmit and receive.
I have not put one in, but it's a simple matter of un-plugging the old
one and pushing the new in its place.
most of the time that's all you need to do, but sometimes you need to
touch the carrier oscillators to make sure they're are centered in the
filter.
remember, at 2.8khz, you'll won't be a popular fellow on a crowded band
Mike, WB8VGE
SunLight Energy Systems
The Heathkit Shop
http://www.theheathkitshop.com/
J e e p
o|||||||o
A man with one clock knows what time it is. A man with two clocks is
never
sure.
On Sep 30, 2013, at 10:12 AM, Basilie Actipis wrote:
Has anybody out there have put the inrad 2.8khz SSB filter in their
paragon
for TX????????
Where is the TX SSB filter is located??????
I know I can use the 6khx AM filter for RX,but I will also install one
for
RX.
Thank you in advance for the help.Bill / N1ASS.73..............
I am re-posting so others have returned from the TT hamfest can read
and
see if anybody has a answer. Thank you.
--
*73........Bill / N1ASS.*
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