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Filter Settings by K1DEU
(See Also Filter Settings
by W4ZB in this document)
(See Also 1.8
Filter Settings in this document)
Here is my favorite filter outlay using **InRad Filters
---2nd, High IF, 8.3 MHz slots---
** 2.8 KHz @ 2.4 position
2.4 KHz OEM @ 2.0 position
** 6.0 KHz @ 500 position
500 Hertz OEM @ 250 position
---3rd, Lo IF, 455 KHz slots---
** 2.8 KHz @ 2.4 position
2.4 KHz OEM@ 2.0 position
** 10.0 KHz @ 500 position
** 400 Hertz @ 250 position
***See Note Below on Changing one more filter
Why I use tandem 2.8 KHz. filters for my favorite SSB bandwidth
parameter, follows below. Note; I only purchased the 1000 MP
after learning that these 2800 Hz filters were available for
this transceiver as voice is my favorite mode.
Human voice studies show that using a total voice bandwidth such
as 3 KHz , which on SSB with a 200 hertz carrier shift would be
a working 6 db down bandwidth of 200-3200 Hertz ), would allow
transmitting a small amount of syllabics and vowel constants in
the human voice, creating higher intelligibility and producing
less fatigue, at the cost of only 500 Hertz more channel
bandwidth than a 2.4 KHz bandwidth. The fatigue is reduced as
the listeners brain doesn't have to fill in the missing parts.
Actually less total bandwidth will be transmitted using two
InRad 2.8 KHz filters with the increased shape factor of 16
crystal lattice poles in tandem, than many other transceivers
using only a single 2.4 KHz , 8 pole filter. A pair of these 2.8
KHz filters with medium strength signals sound as pleasant
listening, as the Good Old Collins 3 KHz filter days.
Transmitting and receiving the lows below 300 hertz is necessary
to hear the vowel constants to know you are operating on the
same RF frequency as the other persons. Transmitting and
receiving the highs of syllabics above 2800 hertz reduces the
need for phonetics as you can actually hear the difference
between a F and Ssss and many other words more easily, also
reducing the fatigue created in the listeners brain as it
doesn't have to guess the missing word parts. To test your
transmitted syllabance signal level , Use your built in audio
oscillator and simply hiss ( open lips slightly and hiss gently,
like a air leak) near your mike ( not into it ) while watching a
peak reading wattmeter. The wattmeter should read as high, as it
does with low and mid pitch humming. And yes; unfortunately
enjoying more of the Lord's designed human voice requires more
bandwidth entering into the population vs. bandwidth debates.
*** Filter notes from my 1000 mp posts, 01 Aug 2000; When
receiving AM the shape factor for the Synchronous detector
receiver is determined exclusively by CF2001, a Murata CFW455G,
6 pole ceramic filter. This filter is 9 KHz at 6 Db down,
widening to 20 KHz only 40 Db down selectable in and out but
hard wired in without options to add any other tandem, steeper
skirt filters before or after it.
Mean while the internal 455 KHz 6 KHz Stock Filter, which is
selectable at the front panel (labeled "6.0K") but also hard
wired in, is CF2002, a Murata CFWHT, 6 pole ceramic filter,
which is 6 KHz at Six Db down, widening to 18 KHz only 40 Db
down. I believe Yaesu should have used at minimum, cheap 11 pole
filters in the 1000MP. Many of us purchase the Yaesu PN# CF2001
for the IF UNIT, FM receiver a Murata CFW455G a 9 KHz filter and
replace the CF2002 a Murata CFW455HT 6.0 KHz filter for better
syllabance bandwidth when listening and transmitting AM. My page
on balanced modulator changes with filter comments at bottom <<<
here >>> also muRata Filters
More filter notes from my 1000 mp posts; The internal 455 KHz 6
KHz Stock Filter used in many modes, and selectable at the front
panel is CF2002, a Murata CFWHT, 6 pole ceramic filter, which is
6 KHz at Six Db down, widening to 18 KHz only 40 Db down. This
is quite a poor shape factor. This physically is a little 11 X 7
mm rectangular filter and difficult to replace with a better
shape factor, much longer one. Click Here for my article on
changing this filter. You are starting properly with a good
shape factor at the hi ( 8.3 MHz ) IF first. Cascading a better
quality low IF filter for rough AM conditions is a expensive
option, which I will add later. With only one default carrier
shift option for both 2.8 and 2.4 SSB filters, I believe I have
located the SSB filters properly. Also the AM filters will not
function in any 250 position so I must use the 250 position for
my two CW filters and the remaining 500 position for AM filters.
The DSP audio filter will further reduce the CW shape below 400
Hertz nicely. When moving the OEM ( Yaesu ) filters, they did
not have ground pins at each end and after mounting them on the
InRad adapter board, I had to ground the case mounting tabs to
the InRad adaptor board ground plane with some braid. Also when
mounting the InRad filters at the OEM soldered in locations , as
InRad has ground pins at each end, I had to heat some solid 22
gauge wire and run through the existing PC board holes to open
them up. No drilling is necessary. InRad will sell you the small
plug in PC boards which hold the filters for $10 apiece. Also,
don't forget to consider using old 455 KHz filters from CB and
Two way business band radios. Nice shape factors in old Motorola
tube type narrow band, business band transceivers.
No IALC might be better on SSB Transmit, it certainly is on AM;
notes from my 1000 mp posts; The other day, after talking to
Gary, WA1OXT, who mentioned that on AM he ran no ALC with his
Transceiver. Therefore I set out to examine my FT-1000MP Rev 5
up. I first set the RF power on front panel fully clockwise. I
was tinkering around on SSB and rotated the internal IALC Pot
fully Clock Wise ( reducing the RF Final IP current limiting ).
Pot was factory set about 20% from Fully clockwise. Yep sure
enough there was less off channel crud ( very noticeably ) 5 and
6 KHz down the band when transmitting LSB, even when cranking up
the Mic gain a extra amount. Before I changed the IALC pot
setting I had rotated the P.MAX pot ( near the 10 and 50 watt
pots ) clockwise and found that the off frequency crud level
rose quickly when going above a CW level of 120 watts, there
fore I set the level to 110 watts. Now after reducing the IALC I
moved this P.MAX pot again finding the CW carrier was about 135
Watts out, ( much higher ) before the off frequency crud level
would start to rise when transmitting SSB. I left it set to
about 125 watts out on CW for a little reserve. Notice, that
here we are using the Normal ALC circuit to limit the max RF
without also current limiting the RF finals MAX Drain Current.
Next the pot labeled " AM " is set for about 15 watts of
quiescent carrier out. My conclusion is that the IALC circuit
introduces a lot of distortion ( off channel shot noise ) when
transmitting SSB, actually making things much worse than better
off channel. I have seen this in a few other solid state
transmitters before. Usually the poorly designed ALC circuits in
some cases simply needed an added, source follower with more
decay release filtering, with a small resistor and large cap in
series across the new low impedance ALC buss. I was barefoot
when doing this. My Spectrum analyzer was a old Drake R4C with a
S9 signal into it and an Commercial Polarad model DU1A Spectrum
Analyzer. I have a high composite voice with a fundamental of 75
Hertz and full range Mic. When testing don't use a few tones or
a string bean ( very narrow ) voice or mike. And its hard to
beat using your ears, with a external SSB receiver with RF gain
off and lots of audio gain. Its very hard to see off channel
shot noise on a fast persistency scope, but very
easy to hear.
Afterwards my old Heath Kit SB-220 ( pair of 3-500Z's ) also
likes the extra drive when tuning up for max CW carrier out and
then over coupling by turning the antenna loading control
clockwise dropping output power about 8 % for better grounded
grid linearity. I don't use any external ALC back to the
exciter, only over coupling at the Final. Yes its a Yaesu
1000MP, dated late 2000. I expect to take the time when ready
for winter to fix this design problem. This crud we all listen
to on the side of many stations doesn't seem to be included in
any reviews of new transmitters. Just putting two tones into a
transmitter and displaying the IMD results is too easy a review.
Personally when I talk to someone, I don't whistle two tones
simultaneously. I remember after my 1958 DX-100 days ( Hi Earl,
K6SE, W8DGP ) that The first well working ALC I experienced was
in the Heath, Triple action level controlled SB-100, where you
could really tromp the mike gain and sound good on and off
channel. Also remember how clean the Central Electronics phasing
rigs sounded off channel without any ALC? If we all paid as much
attention to ALC as we do to our Receiver AGC circuits it might
be a better World. The overall linearity of The FT-1000mp
transmitter on SSB is superb with ALC off. Maybe I'll be lazy
and instead of fixing it, just never use ALC again.
The $10 InRad AGC Modification I find absolutely necessary when
using any mode during lightning storm static interference.
During these short duration, high strength spikes we are forced
to use the fast AGC setting so the receiver will recover quickly
enough as not to miss the first word or character of any signal
weaker than the static. With the original poor design in the
fast AGC setting ,the signal modulation appears on the internal
AGC buss causing unnecessary fatiguing, distortion which is
unacceptable poor design.
Adjusting the FT-1000 MP or most any 100 watt output SSB
transceiver for AM transmission. IE. Is your voice lopsided ?
Yes, if you are a Male.
If you had a symmetrical voice, which a female or a very high
pitched male have , 100% modulation of a 25 watt carrier would
produce 100 watts PEP. Deep sounding males ( thanks to their
larynx ) can easily be asymmetrical ( lopsided ) up to 150%
which would mean that a 12.5 watt carrier would produce 100
watts PEP. I run a carrier level of 10 to 15 watts on AM for
little distortion. I can push it to about 20 watts, but other
fussy people notice the distortion. I also have audio phase
reversal switches on my microphones. With a Oscilloscope you can
quickly get your audio phase properly set for about a negative
going 95 % and well over a positive going 100% ( up to 145% )
modulated carrier. Thus your output wave form would be identical
to your audio input wave form. The last thing we want to do is
over modulate with negative going ( over - 100% ) modulation as
substantial adjacent channel noise is produced when the low
level mixer is cutoff (carrier cutoff). Therefore with a MP (
100 PEP) I recommend 15 watts and a Mark 5 ( 200 PEP ) 30 watts
with audio phase set for more positive going than negative going
modulation. You can feed your mike directly into a scope to
check your asymmetry. But put scope on RF for proper phase
setting as even some factory mikes are backwards. In SSB there
is no need for any phase check.
With no modulation .. RF power level on front panel fully
clockwise. AM position. Set internal carrier level pot to 15
watts output for a MP... 30 watts for a Mark 5. These are the
maximum carrier amounts for an asymmetrical (male) voice !
The 15 watts applies to any 100 watt PEP output transmitter. Now
when you modulate, crank up the Mike gain watching a watt meter
on Average ( not peak ) Power, until the carrier power only
occasionally kicks downward. This downward kick is your carrier
being cutoff, resulting in distortion. No downward deflection
would be distortion free. Without compression or peak limiting a
little downward would be acceptable to keep the average up. If
you monitor yourself with good headphones ( I like Sony CD10's
about $20) , as you bring up the Mike gain you should hear the
distortion as you start to kick your external average watt meter
downward. When set properly with little average downward, now
observe the Internal PO (power out) meter. You should see your
15 watts of carrier and as you modulate your peaks of 100 watts
or slightly higher should show momentarily. Although your
carrier power is only 15 watts your PEP will be 100 watts or
slightly higher. Yaesu automatically disables Processing in AM.
By the manual I set my metering menu hang time to two seconds
(2000 ms) for all functions. For excellent modulation reports I
use a $30 dollar Radio Shack Mike #34069 with a Radio Shack wind
sock plugged into the RCA Phone Patch input on the rear and the
FT-1000 MP's internal TX EQ Menu 4-4 set to #4. And then to roll
off some lows on SSB ( as my voice is too bassy ) : Menu 7-7
SSb-t at 150-3100 or 200-3100 .
Menu Settings with Yaesu 2.0
Filters by W4ZB
Mike, before returning your 2.0 Yaesu filters, first try
setting Menu 8-9 to the following values:
r-LsbcAr
-0.200
t-LsbcAr -0.100
Proc-Lsb -0.100
r-uSbcAr -0.200
t-uSbcAr -0.100
Proc-uSb -0.100
t-A3-cAr -0.100
The
carrier offsets for all of these settings was 0.000. I also
noted the poor RX (and TX) audio with the default settings, but
once I changed to the above settings for my Yaesu 2.0 pair, both
RX and TX audio improved dramatically. I've been using these
settings for the past 3 years in numerous SSB contests on 10
meters including setting the current USA records in CQ WW SSB,
ARRL DX SSB and CQ WPX SSB. The filters you have will work fine
once you change the carrier
offsets. I certainly would consider the Inrad 1.8's if I had it
to do over again, but that would cost another $270 and I frankly
doubt I would notice the difference. BTW, the above carrier
offsets will also greatly improve the performance of the stock
2.4 filters or any Yaesu or Inrad SSB filters for that matter.
73, Bill W4ZV
All
I can say is WOW. What a difference. I have owned my MP (plain
not Mark V) for 4 years and never messed with the carrier
offset. I have the Yaesu 2.0
filters as well as the 2.4. The new settings make the shift and
width much more responsive.
TNX
es 73,
George K3GV
Good advice from Bill, and who can argue with success? ;-)
With the Inrad 1.8's, I've been suggesting -.160 rx offset on my
Web page at
http://www.albany.net/~bg/Yaesu/MPsetup.htm for the past two
years. I would
recommend individualizing your tx offset, based on your
voice/mic and on-the-air tests to maximize contesting punch.
Also, folks may very well prefer a different rx offset when
using the wider filters during non-contesting ragchewing. Easy
menu-setability for the offset is a great feature of the
MP/MkV!!! 73, Barry N1EU
INRAD 1.8 SSB Filters - Radio Settings
QUESTION: Currently I am using the original 2.0 khz
YAESU-SSB-Filter for my rig.
I am planning to buy the 1.8 kHz INRAD-Filters for both IFs.
Will it really make any "hearable" difference ?
RESPONSE: If you use menu 8-9 to offset the receive
carrier point for USB and LSB, you can eliminate having to
retune when you switch between the wide and narrow filters.
A value of -160 works well for me. Tony KM0O
RESPONSE: K2AV" wrote: You will hear the difference
because the skirts for the *pair* are very deep and match each
other. This cleans up a fair amount of stuff from above and
below.
Warning, for some it sounds narrow and takes some getting used
to for casual use, though in an ssb contest it sounds great.I
work the pass band shift with it a lot in a contest.
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