Thanks for tuning in. HamTalk Live will be on
the air shortly. Please stand by. Thanks for
tuning in. HamTalk Live will be on the air shortly.
Please stand by. This episode of HamTalk Live
is brought to you by Tower Electronics. For connectors,
cables, and more, call 920 -435 -2973 or visit
pl -259 .com and by the HamStation. Get your
new radio or antenna by calling 800 -729 -4373
or go to hamstation .com. Good evening, everyone.
This is HamTalk Live. episode number 29 picking
the best receiver to work with the expeditions
Rob Sherwood nc0b recorded live on Thursday September
1st 2016 I'm your host Neil Rapp WB9 PPG thanks
for tuning in to this episode of ham talk live
tonight we'll be joined by the top authority
on receiver performance Rob Sherwood nc0b from
Sherwood Engineering and Rob will talk about
his rankings of all the major rigs and how to
pick the best one for you. We'll talk about that
and your take your calls live in just a few minutes.
Last week Ward Silver N0AX was here to talk about
the Yasme Foundation and his Spurious Emissions
Band. We even had a chance to listen to their
cover song cover of the NCJ that's still stuck
in my head a week later. So if you missed the
show, you can listen anytime at HamTalkLive .com.
You can also listen to the podcast on iTunes,
Stitcher, Google Play, TuneIn, SoundCloud, or
YouTube. Get your questions ready to go for Rob
Sherwood after the introduction. You can call
us on Skype. That username is HamTalkLive. or
you can call us by telephone. The number is 812
-NET -HAM -1. You can also send your questions
via Twitter. Our Twitter handle is at HamTalk
Live, and we'll also keep an eye on the chat
box here on the website as well. So I'll be back
with Rob Sherwood, NC0B, right after this word
from the ham station right here. on HamTalk Live.
This episode of HamTalk Live is brought to you
by the HamStation. For 35 years, the HamStation
has brought new and used radios, antennas, accessories,
and equipment to the amateur radio community.
Give Jeff or Dan a call at 1 -800 -729 -4373
or order online at hamstation .com. HamStation
carries all the major brands like Icom, Yezu,
and Kenwood. Shop from a wide selection of radio
scanners, MFGA accessories, Heil Sound products,
Mirage and Ameritron amplifiers, Cushcraft antennas,
and more. Easy online shopping and fast shipping
are waiting for you at hamstation .com or call
1 -800 -729 -4373. The Ham Station, proud to
sponsor this episode of HamTalk Live. A flashlight
is a case for holding dead batteries. Now, here's
Neil Rapp with more HamTalk Live. Welcome back
to HamTalk Live, the ham station. As you covered
for both new and used equipment, give Dan or
Jeff a call. at 800 -729 -4373 or go to HamStation
.com. Be sure to listen to HamTalk Live every
Thursday night at 9 p .m. Eastern Time right
here at HamTalkLive .com. And if you missed the
show, you can download the podcast from the website
and most popular podcasting websites. Rob Sherwood,
NC0B, was first licensed in 1961 with a novice
license. N8ADB at age 14 in Cincinnati, Ohio.
He upgraded to general class about two months
later and his call sign changed to WA8ADB. He
operated as Portable Zero in the mid 70s out
of Colorado and now lives there just east of
Fort Collins. He upgraded to Advanced and Extra
in the 80s and obtained his current call sign
NC0B. In 1974, Rob founded Sherwood Engineering
offering Drake radio upgrades, which he still
does today. He started testing transceivers in
1976, which now total over 100. That data is
now available online at his website, SherwoodEngineering
.com. You use the first part of Sherwood and
the first part of engineering, so it's S -H -E
-R -W -E -N -G .com. Sherwood Engineering now
offers modifications to many shortwave receivers.
and is an authorized dealer of Japan radio receivers
and still makes parts and upgrades for the Drake
R4C, including roofing filters, crystals, capacitor
replacement kits, and even owner's manuals. Rob,
welcome to HamTalk Live. Thank you, Neil. Nice
to be with you. Great to be with you again. I
get to see you at Contest University. last couple
of years anyway and get to hear all about this
so I thought we would give it a chance for people
to call in and ask some questions and and hear
a little bit about this in case they they haven't
had a chance to check that out One note, as far
as the website, you can also use nc0b .com. It
goes the same place and may be easier to remember.
That would be a lot easier to remember. So nc0b
.com gets you to the same place. Very good. Well,
in your laboratory, you've made measurements
of receivers over the years, and you maintain
a ranking of most of the popular rigs out there
on your website. Tell our listeners what this
list should be used for and then also what it
shouldn't be used for. Well it lists many parameters
of receiver performance and you know sensitivity,
noise floor which are similar, dynamic range
which means receiving weak signals surrounded
by strong signals and things like that but What
unfortunately happens is we become over We pay
too much attention to like the dynamic range
number Which is how it is sorted you in in that
order you have to sort a table in some order
So I've had people say well, I've got a radio
that rates a hundred but there's a new radio
It rates a hundred and two should I sell my hundred?
Well, that's silliness, of course. So you have
to use some common sense. So you look at the
big picture, the numbers in performance for,
like you said, a contest or a de -expedition
or something when we've got hundreds if not thousands
of stations on calling a weak station out in
the Pacific, for instance. You want to have your
receiver good enough to handle what most of your
operating is and don't get get carried away with
with a DB here or there even 10 DB here or there
look at the big picture So these these rankings
that you have While they do rank radios according
to certain performance criteria the differences
those levels are pretty small and most major
transceivers these days have great front ends
anyway. Is that fair to say? Well let's say when
I started doing this the numbers were much lower
in the key figure for a contest or a DX pileup
or something like that were much lower and so
a difference between a radio that was 70 dB versus
80 was extremely significant and let alone a
radio that maybe came out 10 years ago that was
60 or 62 but now radios in general moved up so
if we've got a radio this 90 versus 100 or 100
versus let's say approaching 110 or like 108
which is actually maybe the highest that I've
measured then they're all good so then we have
to say well what what do I What modes do I operate?
Do I work CW? Do I work side bin? Do I like a
radio with knobs? Do I like to run it with a
mouse? What's the reliability? How's the receive
audio? How clean's the transmit audio? So we
really need to weed out the disasters and then
say, Okay, here's my block of transceivers and
I'm going to look at all of these and then pick
something that makes sense and of course price.
We've got radios now that are really good from
$1 ,500 to $15 ,000. Well, that's certainly a
range that's staggering. Although if you really
go back in time and talk about the gold dust
twins, which were Collins radios back in the
50s, they were by today's standards no more expensive
than some of these astronomical prices. It isn't
like we've never heard of extremely expensive
radios even in the 50s, but we have to look at
a broad spectrum of issues including price. Yeah,
so why don't you tell us a little bit about these
measurements and how you go about obtaining them
and maybe a little bit about what ones are kind
of similar so that way we can kind of know what
we're looking at on these tables. OK, I've got
my table up here on another computer. Well, if
you go to my website and you go to the click
on a little banner goes across and it brings
up the table. And we've got several parameters
and the one is the noise floor, which is similar
to sensitivity. If the noise floor is good, the
sensitivity is good. Well, everyone wants to
have a radio that can receive weak signals. So
that's a number that has significance. But we
have to also realize that on most bands, particularly
the lower bands, band noise is dominant over
receiver noise. But like 10 meters, that's a
different story. It's important to have very
good sensitivity on 10 meters because the band
noise is much less. So. we have to think about
what bands we're operating. Also, the last six
years on 10 meters has been phenomenal. And if
you're a contest or just a rag tour, I put up
a 10 meter tower and a 10 meter Yagi about six
or seven years ago. Boy, I was just lucky I got
it up in time. But now we're going down in the
sunspot cycle. So the 10 meter performance relative
to like what's going on in 40 meters will be
less significant until the next round of sunspots.
While we're talking about this, we were just
talking right before the show about the FCC and
how they have established the noise floor. What
have you seen out of the noise floor over the
years? What you're referring to is the FCC actually
asked for documents from industry, from hams
on what's happened to the general noise floor
of the HF bands. particularly in an urban environment.
And I'd say they've gone up about an S unit,
about 6 dB every decade. So when I moved to the
Denver area in 1969, it was pretty quiet, but
it is significantly noisy. And you say plasma
TVs, switching power supplies, computers, of
course, have switching power supplies, fluorescent
lights, things like that. There are routers for
your internet. Everyone's got internet where
your routers put out birdies and things like
that. So the noise level is a significant problem
today, particularly in the city. So this is going
to give you a rating that's going to help you
fight that a little bit. Well, if you're lucky
enough to live in an urban environment, I mean,
if you're lucky enough to live in a rural environment,
then you've got a better shot. at hearing weak
signals on 10 meters, for instance. But if you're
in the city, it's going to be more difficult.
So the ranking of the sensitivity, I'll get a
phone call and someone will say, I want to work
more DX. What receiver should I purchase today?
And so unfortunately, if you're living in the
city like I do part of the time, then that noise,
urban noise level is maybe the most dominant
thing that limits what you can do. But the other
thing that's important is your antenna. And we
want a good receiver, of course, but if you've
got an antenna that's 25 feet off the ground,
then that's going to be a limit, too. So as we
chatted earlier, certainly your receiver is important,
but your antenna is important. Your skill to
work at the expedition or to work a contest is
important. So all these things are part of the
picture. Okay and let's get back to the chart
too and look at some of these other measurements
and how you take those. Okay well like if we're
measuring noise floor sensitivity we have a calibrated
signal generator, we have the receiver, and we
feed in a signal. So we make that measurement
and then there's other measurements like Blocking
so when the radio starts to compress as far as
it it's not linear anymore We measure the front
end to see well Is it got enough selectivity
keep another station that's on another band that
might be five miles away out of my radio? The
filters of course are not Have if do not have
infinite rejection, so we may we measure that
and then of course what this table is sorted
by in order of performance is one thing, close
in dynamic range. And that again, dynamic range
means we're trying to work that weak station
and all sorts of strong stations are around it.
Now that ranking is more important for the CW
operator than for sideband. And you say, well,
why would that be? Well, on sideband, if there's
a station three KCs away or five KCs away, he
has transmitted splatter products not because
he's being a bad operator but the amplifier in
our radio that puts out 100 watts let's say has
a certain level of distortion so if that distortion
products that spread out over several kilohertz
like as much as 10 are the dominant factor well
then We might not be able to receive that weak
signal because of a station three or five cases
away, but on CW Signals are much narrower or
at least they should be they don't have key clicks.
So in that case That's why I say this ranking
was really oriented to CW DXing contesting and
that's when that number is most important So
if you got a phone call and somebody said hey
I want to pick out the best rigged work, let's
say the Mouve Island, the expedition coming up.
What are your top two choices or top three choices?
What are you going to tell them? All right. Well,
I'm going to say don't consider the top two or
three. Look at the chart and say, well, let's
look at the top 10, maybe the top 15 or even
20. We have to say what's good enough most of
the time. Now you could always say I want the
best one there is, but there's other aspects
of radio performance and what's important to
you depending on the modes and what maybe how
you're hearing is to me a really clean audio
is important but someone else they don't even
notice distortion and things like that so as
i mentioned back in the time when the classic
radios went away your collins and your drake
they had pre -selectors the performance was in
the 70 dB range, approximately, and then the
upconversion radios came along, like the TR7
was the first one, that's a Drake, but then your
Kenwoods and your Yezus and all that, everybody
went to a radio that didn't have mechanical things
like pre -selectors. Of course, what was the
most amazing pre -selector was the R390A, the
Collins R390A and the spin -offs that were other
OEMs. So that went away with the design changes
as Solid State came in and So we couldn't have
a mobile rig that you could hold in the palm
of your hand with a preselector in it. But then
we had radios that were almost all the same for
about 20 years. And they really were not adequate
for CW contesting and de -expeditions. They barely
worked for sideband in the crunch conditions.
And that's when really my chart became significant.
that in one case I modified a Drake R4C and that
moved to the top of the chart and then the 10
tech Orion one came along and that was the first
solid -state radio that outranked that modified
Drake and Pushed the dynamic range number up
into the 90s. So Really if you've got a radio
that I always have said 80 to 85 is good enough
most of the time, but you kind of want a little
safety factor. So let's say we're going to say,
I want a 90 dB radio. Well, then you've got a
wide choice because they've gotten better and
better every year or every, say, few years. And
so there's a whole slew of radios that are going
to fit that minimum requirement. And then we
say, OK, we've got this list now. We're going
to look at all those other aspects. Very good.
So it's not just about the rig folks. It's your
antenna your skill and What your preferences
are and other things like, you know, how clean
the audio is and the transmitter all those kinds
of things so lots to consider but If you're going
after receiver performance go over to NC zero
B calm and take a look at at Rob's numbers and
he's got them all right there. So let me give
you a number like you said to the top one or
two. We'll look at the top one or two or two
or three. We've got a flex radio which of course
is run with a mouse although they now have a
product that gives you knobs. They cost almost
as much as radio and we have the K3s from Ellicraft
out of California and these numbers are over
a hundred. So they're Significantly above my
minimum standard. I say we really want an 85
db radio As a round number you say well, what
about 84 83? Let's don't go nitpicking like that.
But so we've got Many choices from many different
companies that are going to be 85 or better in
that in that Right hand column. That is how I
sort my measurement test, but then look at the
other things too Very good. Well, we have some
questions from some of our listeners and I'm
sure we'll get some more so we're going to be
Coming back here in just a minute and take your
calls with Rob after we pay a few bills So right
now we have this message from Tower Electronics
here on HamTalk Live. This episode of HamTalk
Live is brought to you by Tower Electronics.
Tower Electronics has been the Ham's dime store
since 1978, bringing connectors, antennas, cables
and other parts to the world. Scott and Jill
travel the country bringing their store to you
at HamFest, but you can also order online at
PL -259 .com or by calling 920 -435 -2973. Stock
up on those supplies like PL -259 and end connectors,
audio cables, mobile antennas, and hamsticks.
Their silver plated end connectors are even in
use on the International Space Station. Tower
Electronics is a dealer for MFJ, Comet, Daiwa,
OPEC, Workman and HamPro technologies. Tower
Electronics online at pl -259 .com. Proud to
sponsor this episode of HamTalk Live. A clean
house is a sign of a broken radio. You're listening
to HamTalk Live with Neil Rapp. Join the conversation.
Call us on voice with Skype at HamTalk Live or
give us a call at 812 -NET -HAM -1. That's 812
-638 -4261. Now, here's more HamTalk Live. We'd
like to thank Scott and Jill at Tower Electronics
for sponsoring the show tonight to help bring
HamTalk live to you. They'll be at the Shelby,
North Carolina Ham Fest this weekend and will
be coming soon to Findlay, Ohio, Peoria, Illinois
and Cedarburg, Wisconsin. Call 920 -435 -2973
or visit their website at PL -259 .com. Be sure
to listen to HamTalk Live every Thursday night
at 9 p .m. Eastern Time right here on HamTalkLive
.com. Also check out our Facebook page and our
Twitter feed. Just search for HamTalk Live. Alright,
it is now time for your call So if you have a
question for Rob now is the time to call that
number is eight one two net ham one eight one
two six three eight four two six one or you can
Skype your question at ham talk live or you can
tweet and at ham talk live or you can post it
in the chat room and we do have a couple of Tweets
here and we also have a call. So we'll take this
call right here. Hello. Who's this? Hi, this
is Marty Casey one CWF. Hi, it's chicken with
fries. How you doing Marty? Doing good. So I
have a question. Yeah, what's your question?
Yeah, typically I call when I have a question
I was just curious, Rob, what is the radio that
you currently use as your daily driver, day to
day? If you were to walk into your shack right
now, what is your primary radio? Well, I really
have two. And one is the Kenwood TS990S, which
is their big... Hang on a second. Did you hear
that, Marty? A Kenwood? Yes, he said a Kenwood
990S. Yes, I heard that. OK, I just want to make
sure you heard he said Kenwood 990S. OK, Kenwood.
OK, go ahead. Go ahead, Rob. OK, so actually
I have three operating positions in my shack
and the left position has an ICOM peer analog.
transceiver, the old ICOM -781 that has a CRT
in it and it came out at least 25 years ago.
And that's my reference analog radio because
digital radios sometimes have funny artifacts.
So if I hear something that sounds weird, and
of course I probably had virtually every modern
radio through the shack at some point in time.
a lot of them in a contest. So if I hear something
funny, I need to be able to go back to a reference
radio and then switch back and forth. So I've
got a classic analog and then I have a fairly
modern, a few years old Kenwood. I have an ICOM
Pro 3 and I even have that little ICOM 7300 that
just came out soon before the Dayton Hamvention
that's a direct sampling radio. So I use them
all. As a matter of fact, Was on the air last
weekend and then we're trying to figure out which
band to be on for one of my normal schedules
Conditions are kind of crazy and I change bands
by changing chairs. So I wouldn't say that I
have Don't just say I've got that one Kenwood
I've got a Kenwood and icons and and I've used
the flex and the Anna and so I've used a on a
regular basis. I use several brands Yeah, I think
I think that's interesting. I think a lot of
people would be Kind of interested to see what
you use obviously because you know that you know
better than most I find it interesting how you
kind of have like one from each of I guess what
you can consider the three categories an old
old analog radio a more modern radio with DSP
and then an SDR Very very cool how you kind of
all three categories, and I think Neil's quite
excited that one of them is the TS -990 Well
one thing, you know, I've been testing in the
laboratory since 1976 and then my first article
was a Looked at really dynamic range and radios
that were having problems and how to cut How
could I fix it which in that case was the Drake
R4C back in? 1977 ham radio magazine a wonderful
magazine. Unfortunately, we don't have anymore.
It was much more technical oriented than current
magazines, but the The laboratory obviously gives
us numbers to get a good starting point, but
then in the last nine years since I have my contest
station out in the country, east of Fort Collins,
Colorado, it's been fantastic to use these in
CW contests and sideband contests and get to
use the SDRs and the analog. regular DSP radios
and use a wide range and see how they really
sound and are they easy to use and can I be efficient
in a contest. So you really getting your hands
on is important. Yeah, that's cool. I find it
interesting that you contest or I assume that
you contest with the 7300 because When I think
about radios, I think of the 781 and the TS -990
as really contest -grade, big dual -receiver
radios, and then the 7300 is more of an entry
-level radio. Do you think the performance is
really getting there with the SDRs? Well, with
the Flex and the Anon, definitely, and I've used
those in C2B contests. I haven't used the 7300
yet because it just came out and I got one just
in time for Contest University and also the ICOM
7851 was on alone temporarily for a few weeks.
But of course the contest season won't start
again until October at least in my case. I mean
there was a 10 -10 contest that some people think
10 -10 is a contest or not but I like it. And
I've won Colorado a few times. But I haven't
had a chance at all to put the 7300 in a contest
environment yet. It's too soon. But I will this
fall. Well, thanks so much. I think you kind
of answered all my questions. But I'm intrigued
to see how the 7300 performs in a contest environment.
Not so much about the performance of the receiver,
but how with the With the interface, it's such
a small package on how you can manipulate your
contest, which will be interesting to see. Thanks
so much for taking my call. Okay, very good.
Well, it will be fascinating to use it. Now,
I'll mention that I've used the KX3 in two contests.
Now, that's a radio that's smaller than the 73
- That's a small radio. Thanks to Ella Craft,
they loaned me a KX3 and I was on the air from
Easter Island for three days. Not as a de -expedition,
it was a trip with my wife and I was on the air
each morning and each afternoon and that was
just a kick. I was running 12 watts on a battery
from Easter Island. So that was good too. Yeah,
there must have been plenty of people wanting
to talk to you there. It's cool with the small
radios there. Yes, yes. But you're right. You
need good ergonomics. Whatever radio it is, it
needs to be easy to use and not a chore. Right.
That's what I'm interested in, with how ICOM
came out with the 7300 with the touch screen
and everything. Uh, I'm intrigued to see how
you think of it after using it in a contrast,
uh, contrast and interested. And I wonder how
it will compare to when I know icon just, uh,
and, uh, they just released, uh, they just announced
the, uh, boys at the 76th time, how that, how
that will, uh, how that will play in a contest
environment. Thanks so much for taking that.
Sure. Thank you, Marty. Appreciate the call.
Bye bye. Bye bye. Mentioning the 7610, what we
don't really know is it a spin -off of the 7300,
which I hope it is, or is it a Mark II version
of the 7600, which is a standard upconversion
radio with DSP. They didn't say. Yeah, it's going
to be interesting. I'm giving Marty a hard time
about the Kenwood 990 because that's the one
that I keep drooling over but While we're talking
about icon and the and the 7300 I know There
were a lot of people that were really surprised
when the 7300 came out and they went to your
charts to look and see where it was and it shot
right up into the top 10, up against a lot of
these other radios. So why don't you just briefly
talk about overall impressions of the 7300 so
far? Okay, and it's one thing we need to discuss
is testing of direct sampling radios is not straightforward
like our radios we've had now forever. Whether
it was an old Drake or a Collins, or a TS -590,
which is now a $1 ,300 radio, they don't act
the same way. So a direct sampling radio, the
distortion products are somewhat constant. All
our legacy radios you feed in a signal and you
keep increasing the test signal levels and eventually
the distortion products start appearing above
the noise floor of the radio and then you drive
it harder and The distortion products just go
up about a three to one rate That's not the case
with these direct sampling radios at all. So
it's hard to compare and because the direct sampling
will have Modest distortion all the time and
if it's covered up with band noise, we don't
care but It sort of has a brick wall that at
some point boom it goes into horrendous overload.
So it's just totally different Very good. Well,
I'm you know, the front end overload I know is
has been a bit of an issue on it and I'd like
to try one out maybe one of these days I'll try
one but it sure has taken the ham radio world
by storm that's for sure and a lot of cool features
that you wouldn't normally see at that price
level for sure. Right and let me make some more
comments about the details you mentioned the
testing was interesting that it has a feature
called IP plus which is a more consumer term
for something called dither which sounds like
Nonsense, but it did two things it It raised
the noise floor which meant it was less sensitive
and it raised it a lot more than 10 DB So an
80 meters you wouldn't care but in 10 meters
you would so I never run it and it it also was
one of the strange things where because The noise
in its dither which really shouldn't be there
Covered up the lower level distortion products
that made the number kind of inflated So if you
read the footnote you really should read the
footnotes on my website And I'm suggesting don't
run it unless you have a real need for it. It
does not make it that Crash point where the radio
just goes nuts with as with any direct sampling
radio It doesn't change that in the slightest.
It just affects the lower level measurements
the other thing is Probably not the perfect radio
for field day unless you've got Band filters
because it's got a really wide front end. You
mean it's an entry -level radio. It's small It's
fun to use. I like it. I own one but the if you're
on 20 meters and you had another station on field
day on 40 meters and let's say another station
on 17 meters that front end only knocks those
two other bands down 10 dB. That's not much.
So if you're running a multi -field day station,
you better have band filters, bandpass filters
for each band. And if you're running... a CW
station and a sideband station on the same band
well then of course the bandpass filter wouldn't
help at all so you just have to realize what
its limitations are and what its strengths are
but it is very easy to use the touchscreen works
very simply it's not a hindrance and it keeps
you from having to dig into all sorts of menus
most of the time all right well let's take some
of these questions here from Twitter we've got
several of them The first one says, what do you
think about the new SDR radios versus a Drake
R4C with all the upgrades you can get? All right.
I know I didn't send that question in. Well,
I actually did contest just a few years ago with
a modified C line with my mods in it and 10 tech.
Orion 2 with the Eagle upgrade and I actually
used the Eagle upgrade sub receiver because I
was checking that out for Jack Birchfield So
they both perform well But in this day and age
if you're a contest or you got to have computer
logging That's a week's point for anything like
a Collins or a Drake or a hammerland or any of
the old radios They don't talk to your computer.
Now if you're running a single band contest like
I was on 160 I just had to give up the fact my
log had no idea what frequency I was transmitting
on. If you look at the chart on a modified C
line, you'll see it fits that criteria of it's
about 85 dB. I think it's 84, but it makes the
cut. But then there's other radios that one thing
that was a shock when the FT2000 came out, it's
not that long ago, maybe Approaching 10 years
maybe not quite that long and its numbers were
like in the 60s whether you looked at the a double
RL test or my test or anyone else and so that
was a case where you you see you found it way
down on the chart so again look at the look at
the chart and say okay, I'm gonna sort of make
a cutoff and you know 85 plus and So the sea
line was there and your TS 590s there A lot of
radios are vastly different prices. The Hillbillings
there for $18 ,000. The 7851 at 105, but again,
it's like $13 ,000. But you've also got a KX3
for, what is it, $1 ,000. So a lot of options.
Very good. Thanks to Brian, KC9KUH, for sending
in that question, by the way. And Dr. Scott Wright,
K0MD says, if someone with a superb antenna system
who's operating largely DX contesting, what two
performance criteria are most important? Well,
if it's CW, the close end dynamic ranges, because
that DXpedition you're going to have thousands
of stations that are up two, up three, up four,
that are going to be calling and you're going
to be hearing a lot of those. And they're going
to potentially intermod on top of the DX station.
And of course we're all going to have some lids
that are going to be calling on frequency. Not
much you can do about that. So for the CW, either
a contest or a DXpedition, look at the close
in dynamic range, which is what the tables sorted
by. And that's why I did it that way. And that's
really the big number. Almost every radio made
is sensitive enough. So that's not a limit. And
unfortunately, if you're in the city, you're
probably not going to ever be able to realize
that sensitivity that's there. And again, that
sensitivity is really important on 10 meters,
12 meters, 15 meters. It's almost meaningless
on 40 meters during the night time. But then
don't forget Depends on time of day, and you've
got good antennas. I ran into a case with one
OEM that the radio didn't have a preamp on 80
meters, for instance. And during the daytime,
I was listening at 8 .30 in the morning, and
I couldn't copy this one station on the modern
radio, but it could copy it on my 25 -year -old
icon. So we do need sensitivity, even on the
low bands, particularly at daytime. Amazingly,
when I work 160 contests, and I'm working JA's
from Japan, about seven o 'clock in the morning,
well, the sun's coming up, but the band is really
quiet. So it's amazing that here you're on the
lowest hand band that we have. Well, there are
some below the broadcast band, but they're kind
of experimental, that we do have to be concerned
about sensitivity. It I guess if you say which
to dynamic range at the right column sensitivity
the left column But keep your preamp off unless
you need it. I have a friend who has the 7300
I was talking to him on 40 meters And he had
the preamp on and he was complaining about some
some overload You don't need a preamp on the
7300 on almost any band except maybe 10 and 12
certainly not 40 meters and keep it off so If
you want to minimize the radio's chance of overload,
only use a preamp when you need it. All right,
we've got one minute left and I've got one more
question here. What do you see the OEMs doing
with SDR? ICOM seems to be going to SDR. What
do you think Yezu and Kenwood are going to do?
Are they going to stay superheterodyne or follow
suit? And then what are the advantages for the
superheterodyne? Well, if you look at the top
two you've got you've got the flex you've got
the ks3 and they really measure very similarly
So they're both good. So I just say don't don't
pick a radio on architecture pick it on what
makes what makes sense for you, but the the ICOM
really shock the world with the 7300. I mean,
they've sold thousands of them. It's hard to
get on the air and not hear somebody talk on
a 7300. So I think that ICOM will be going in
that direction. The 7851 may be the last really
big analog front end type of radio, super heteronet,
let's use that term, that comes out of the big
three out of Japan. I would expect the Yezu and
Kenwood to be looking at it seriously. We'll
just see what the sales figures are over time.
If the 7610 is a big brother for a 7300, it might
be a monster seller like the 7300 has. It'll
probably be a three or four thousand dollar radio.
So the question everyone's asking, what is Ellicraft
going to do? Is there ever going to be a K4?
Will the K4 be a SuperHat radio because the K3S
is a really good radio and maybe they'd make
it bigger with the band scope build -in and maybe
a power supply build -in and all that kind of
stuff, but that's the big unknown. But there's
nothing wrong with either one. They both work
and really look at price, features, size, do
you need a computer to run it, all that kind
of stuff before you look at the architecture.
Very good, Rob. Thank you so much for coming
on the show. That is a wrap for this week's edition
of HamTalk Live. I'd like to thank my guest,
Rob Sherwood, NC0B of Sherwood Engineering and
everyone out there in cyberspace for listening.
Calling in invite you back next Thursday night
at 9 p .m. Eastern time and our plan is for Skylar
Fennel W or a KD zero WHB the Bill Pasternak
young ham of the Year Award winner to be with
us. He's still working on his Schedule, so hopefully
that will be our guest next week for a list of
all of our upcoming guests visit hamtalklive
.com So for now, this is Neil rap WB nine VPG
saying seven three seven five and may the good
DX Be yours!