Re: UBITX v4 - transmission power problem with FT8 emission.
Check power control option built with wsjtx or Jtdx. It should be maximum to obtain max power.
When transmitting SSB, the radio works with power up to 10W without any problems.
However, when working with the FT8 emission, the power drops to 1W and I am unable to increase it in any way.
The signal strength from the computer is set to maximum.
After connecting another radio to the computer everything works fine.
73!!! Kris
|
UBITX v4 - transmission power problem with FT8 emission.
When transmitting SSB, the radio works with power up to 10W without any problems.
However, when working with the FT8 emission, the power drops to 1W and I am unable to increase it in any way.
The signal strength from the computer is set to maximum.
After connecting another radio to the computer everything works fine.
73!!! Kris
|
Re: Easy 20 Watts with any qrp
#bitx40
The transistor is IRFP 150 that is being used in my easy Bitx after the driver of 2 no's 2n3904 .
By mistake I mentioned the FET as IRF150 it's IRFP150.
The make is Harris .
Picture?attached?
Regards?
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
toggle quoted message
Show quoted text
On Mon, Mar 27, 2023, 6:07 AM Dan Eggers N7DE < N7DE@...> wrote:
I think that is wonderful, and when you remember the name please send it to me.? I am at the point where I sort of forget things temporairly also, so that is no big deal.? Oh, well.? I am interested in a
lot of different technologies that all take up my time, but of course I intend to continue to stick with CW.? ? ? 73, Dan
??
The digital voice mode that could possibly replace ssb is freedv. It is actually two things that work together.
First, the voice is converted into a stream of very few bits per second. A usual voice stream like that of telephone uses about 64,000 bits per second. Freedv codec reduces it to 700 bits per second. This is at the cost of reduced quality. However,
it is much better that SSB on 80 meters.
The second thing is an HF modem that can work at 700 bits per second. This is a weird one. On HF as signals bounce off the ionosphere and arrive at the rx antenna, you can have a situation where the same signal can arrive taking different paths
and hence at different times , overlapping itself. This reduces the number of times you can rapidly change the frequency of the signal. This is why FT8 works so well, it is so slow that fading, et al doesnt affect it. So, what the freedv modem does is that
it transmits a number of parallel ft8 like signals as separate tones within the same audio which when added up give you higher bandwidth. There is a very impressive name for it that escapes me now.
Our plan is to add freedv into the sbitx, making it the the first radio to support it natively.
- f
Gordon:
Either RadComm or Sprat had an article how students in England were fascinated by Morse code. When asked why, they replied that "voice" (SSB) didn't interest them because they could do that with their cell phone. But Morse was "better"
because their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
Well, for several years now we have observed some thing very fascinating among middle schoolers in our local school.
They are not interested at all in walkie-talkies
They are not interested at all in HF radios
Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they will grab onto and play with until you have to pull them away kicking and screaming with their parents,
Is a Morse code key!!!
At every school open house that we hold we now always provide multiple Morse code keys and it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of someone sending Morse code
We have two 6th graders in a very small school that are already doing about 10 words per minute. I sent 30 minutes worth of code to them two weeks ago?
It is astonishing the attraction that Morse code has for these middle schoolers
Meanwhile, across town, at the school devoted to future police and fire high schoolers, they have an extremely active contesting high school I am radio club and I am told that their best operator can do over 30 words per minute and they routinely make
hundreds and hundreds of contacts at voice and CW in contests. ?
Our local ham radio club would have a hard time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human nature is the same. And there are certain number of us who really love the auditory and tactile tickling that only Morse code gives¡. And by the way it is the first digital, the only digital that can be decoded by
the human brain without much else.? End it enjoys an order of magnitude or two advantage over voice In terms of threshold signal to noise ratio!!!?
On Mar 26, 2023, at 13:23, Dan Eggers N7DE <N7DE@...> wrote:
?
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain era.
Best wishes.? ? ? ?73, Dan
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster.? That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe you use solar cells and power
conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
--
Jack, W8TEE
|
Re: Easy 20 Watts with any qrp
#bitx40
My intention to use IRFP150 with 200mw drive was for pure experimentation. Secondly i wanted a solution for changing the mosfet if someone using our kit burns the mosfet either while setting the bias voltage or due to high swr.
?The IRFP150 which I already had for some other project seemed a logical choice for me as it was very convenient to mount on the rear cover and just connect the legs to the pins where the IRF510 inserts, in this way it would be easier to change the FET if somehow it got burnt. The PCB pad is quite delicate and if someone was to remove the FET mounted on the pcb it could damage the pads.
Overall the experiment worked and the RF output was 20 watts with just two numbers of 2n3904 as drivers. keep in mind this FET wan't give much power above 7 MHZ. This is good for lower bands only.
Now it's not my suggestion to use IRFP150 , it depends on your taste as to what you want either the power or the type of FET to use. I just shared my experiment result with you all.
Best of 73's
DE VU3SUA
Sunil Lakhani
/
FUSION RADIO STORE
OUR NEW YAHOO GROUP
Tracking Link For Shipments:
For EMS AND REGISTERED
|
Gaah, they beat us to it. The good news is, in open source, we just get to use it all the same! I am off to read the code... - f
On Mon, Mar 27, 2023, 6:52 AM Gerald Sherman < ve4gks@...> wrote:
I am expecting delivery in a few days of an RS918 (originally
designed by M0NKA).? It supports Freedv, just for your
information.
Gerry Sherman
Sent by the Linux Thunderbird
On 2023-03-26 23:35, Ashhar Farhan
wrote:
The digital voice mode that could possibly replace
ssb is freedv. It is actually two things that work together.
First, the voice is converted into a stream of
very few bits per second. A usual voice stream like that of
telephone uses about 64,000 bits per second. Freedv codec
reduces it to 700 bits per second. This is at the cost of
reduced quality. However, it is much better that SSB on 80
meters.
The second thing is an HF modem that can work at
700 bits per second. This is a weird one. On HF as signals
bounce off the ionosphere and arrive at the rx antenna, you
can have a situation where the same signal can arrive taking
different paths and hence at different times , overlapping
itself. This reduces the number of times you can rapidly
change the frequency of the signal. This is why FT8 works so
well, it is so slow that fading, et al doesnt affect it. So,
what the freedv modem does is that it transmits a number of
parallel ft8 like signals as separate tones within the same
audio which when added up give you higher bandwidth. There is
a very impressive name for it that escapes me now.
Our plan is to add freedv into the sbitx, making
it the the first radio to support it natively.
- f
Gordon:
Either RadComm or Sprat had
an article how students in England were fascinated by
Morse code. When asked why, they replied that "voice"
(SSB) didn't interest them because they could do that
with their cell phone. But Morse was "better" because
their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
Well, for several years now we have observed
some thing very fascinating among middle schoolers
in our local school.
They are not interested at all in
walkie-talkies
They are not interested at all in HF radios
Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they
will grab onto and play with until you have to
pull them away kicking and screaming with their
parents,
Is a Morse code key!!!
At every school open house that we hold we
now always provide multiple Morse code keys and
it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of
someone sending Morse code
We have two 6th graders in a very small
school that are already doing about 10 words per
minute. I sent 30 minutes worth of code to them
two weeks ago?
It is astonishing the attraction that Morse
code has for these middle schoolers
Meanwhile, across town, at the school devoted
to future police and fire high schoolers, they
have an extremely active contesting high school
I am radio club and I am told that their best
operator can do over 30 words per minute and
they routinely make hundreds and hundreds of
contacts at voice and CW in contests. ?
Our local ham radio club would have a hard
time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human
nature is the same. And there are certain number
of us who really love the auditory and tactile
tickling that only Morse code gives¡. And by the
way it is the first digital, the only digital
that can be decoded by the human brain without
much else.? End it enjoys an order of magnitude
or two advantage over voice In terms of
threshold signal to noise ratio!!!?
On Mar 26, 2023, at
13:23, Dan Eggers N7DE <N7DE@...>
wrote:
?
Thank
you?for the
information.? I see you and I are both CW old
timers.? So far we have lost about half of the
CW people without any real replacements coming
along, but you and I came along during a
certain era.
Best wishes.? ? ? ?73,
Dan
Eventually there will be something that
replaces analog single side band voice. But it¡¯s
not yet here. ? And I think I have been doing CW
for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at
11:51, Dan Eggers N7DE <N7DE@...>
wrote:
?
I have been
sending Morse code now for 57 years,
and I will just continue to send Morse
code, but since you seem to be very
knowledgeable is there a digital voice
modulation system that will eventually
replace SSB?
Thank you.? ? ?
? ? 73, Dan, N7DE?
Single side band typically requires a 10
DB signal to noise ratio for useful
communications in a disaster.? That is,
the efficient transfer of information
My contrast, using the same base
noise in that bandwidth, data
communications of moderate speed can
tolerate SNR into low single digits,
and still move efficient
communications far faster than voice
Low data rate redundant digital
communications can tolerate signal to
noise ratios a couple orders of
magnitude lower SNR
These comparisons are widely
available
It¡¯s no secret why people who are
very involved in the (voice) national
traffic system often have kilowatt
amplifiers. ?
And people who are into JS8 ?don¡¯t
need them
So there are different requirements
for different parts of our hobby
On Mar 26,
2023, at 11:33, Dan Eggers N7DE
<N7DE@...>
wrote:
?
I used
20 watts for a long time, and
I have had a number of people
refuse to talk to me, because
my signal was too week, so
more power is needed.? I have
written a booklet about solar
cells, and maybe you use solar
cells and power conversion,
and that is also a very
interesting area, but I also
want to be able to talk to
people.
? ? ?
73, Dan, N7DE? ?
With respect, Dan, "need"
isn't an actionable or useful
concept, especially in QRP land.
I live on a sailboat and am
currently in Tampa Bay. With a
couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55
PM, Dan Eggers N7DE wrote:
20
w is -7 dB, and that is
too far down.? it is
getting close to -10 dB
down.? You need to be at
50 w, and that is only -3
dB down.? What I have used
for low cost has been an
MRF455 in an EB63A board
from Communications
Concepts, and it works
very well.
?
However,
the Chinese are selling a
100-w amplifier with a
heatsink that has had the
level set, and they also
sell a lowpass filter
board XDT LPF200 for 3 -
30 MHz at a reasonable
price that works very
well, so these days there
really isn't any reason to
"build your own"
amplifier.?
?
The
main thing I am saying is
that you need more power
so that you can be heard.?
I went through enough
Electrical Engineering
courses that I am now an
Electrical Engineer, but I
do not think I am going to
try design amplifiers from
scratch myself.
?
I
am very grateful for all
of the people who helped
produce the UBITX 6,
because I think that has
been the only low cost
real general coverage
transceiver that is out
there.? ? ? ? ? ? ?73,
Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET
is? IRFP150? And Not IRF150
, sorry for the typo.
I will edit at the end of
the video..
The FET i have used is
Harris IRFP 150
It works great with not much
heat at 35 V .
Regards
Sunil vu3sua
--
Jack, W8TEE
|
I am expecting delivery in a few days of an RS918 (originally
designed by M0NKA).? It supports Freedv, just for your
information.
Gerry Sherman
Sent by the Linux Thunderbird
On 2023-03-26 23:35, Ashhar Farhan
wrote:
toggle quoted message
Show quoted text
The digital voice mode that could possibly replace
ssb is freedv. It is actually two things that work together.
First, the voice is converted into a stream of
very few bits per second. A usual voice stream like that of
telephone uses about 64,000 bits per second. Freedv codec
reduces it to 700 bits per second. This is at the cost of
reduced quality. However, it is much better that SSB on 80
meters.
The second thing is an HF modem that can work at
700 bits per second. This is a weird one. On HF as signals
bounce off the ionosphere and arrive at the rx antenna, you
can have a situation where the same signal can arrive taking
different paths and hence at different times , overlapping
itself. This reduces the number of times you can rapidly
change the frequency of the signal. This is why FT8 works so
well, it is so slow that fading, et al doesnt affect it. So,
what the freedv modem does is that it transmits a number of
parallel ft8 like signals as separate tones within the same
audio which when added up give you higher bandwidth. There is
a very impressive name for it that escapes me now.
Our plan is to add freedv into the sbitx, making
it the the first radio to support it natively.
- f
Gordon:
Either RadComm or Sprat had
an article how students in England were fascinated by
Morse code. When asked why, they replied that "voice"
(SSB) didn't interest them because they could do that
with their cell phone. But Morse was "better" because
their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
Well, for several years now we have observed
some thing very fascinating among middle schoolers
in our local school.
They are not interested at all in
walkie-talkies
They are not interested at all in HF radios
Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they
will grab onto and play with until you have to
pull them away kicking and screaming with their
parents,
Is a Morse code key!!!
At every school open house that we hold we
now always provide multiple Morse code keys and
it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of
someone sending Morse code
We have two 6th graders in a very small
school that are already doing about 10 words per
minute. I sent 30 minutes worth of code to them
two weeks ago?
It is astonishing the attraction that Morse
code has for these middle schoolers
Meanwhile, across town, at the school devoted
to future police and fire high schoolers, they
have an extremely active contesting high school
I am radio club and I am told that their best
operator can do over 30 words per minute and
they routinely make hundreds and hundreds of
contacts at voice and CW in contests. ?
Our local ham radio club would have a hard
time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human
nature is the same. And there are certain number
of us who really love the auditory and tactile
tickling that only Morse code gives¡. And by the
way it is the first digital, the only digital
that can be decoded by the human brain without
much else.? End it enjoys an order of magnitude
or two advantage over voice In terms of
threshold signal to noise ratio!!!?
On Mar 26, 2023, at
13:23, Dan Eggers N7DE <N7DE@...>
wrote:
?
Thank
you?for the
information.? I see you and I are both CW old
timers.? So far we have lost about half of the
CW people without any real replacements coming
along, but you and I came along during a
certain era.
Best wishes.? ? ? ?73,
Dan
Eventually there will be something that
replaces analog single side band voice. But it¡¯s
not yet here. ? And I think I have been doing CW
for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at
11:51, Dan Eggers N7DE <N7DE@...>
wrote:
?
I have been
sending Morse code now for 57 years,
and I will just continue to send Morse
code, but since you seem to be very
knowledgeable is there a digital voice
modulation system that will eventually
replace SSB?
Thank you.? ? ?
? ? 73, Dan, N7DE?
Single side band typically requires a 10
DB signal to noise ratio for useful
communications in a disaster.? That is,
the efficient transfer of information
My contrast, using the same base
noise in that bandwidth, data
communications of moderate speed can
tolerate SNR into low single digits,
and still move efficient
communications far faster than voice
Low data rate redundant digital
communications can tolerate signal to
noise ratios a couple orders of
magnitude lower SNR
These comparisons are widely
available
It¡¯s no secret why people who are
very involved in the (voice) national
traffic system often have kilowatt
amplifiers. ?
And people who are into JS8 ?don¡¯t
need them
So there are different requirements
for different parts of our hobby
On Mar 26,
2023, at 11:33, Dan Eggers N7DE
<N7DE@...>
wrote:
?
I used
20 watts for a long time, and
I have had a number of people
refuse to talk to me, because
my signal was too week, so
more power is needed.? I have
written a booklet about solar
cells, and maybe you use solar
cells and power conversion,
and that is also a very
interesting area, but I also
want to be able to talk to
people.
? ? ?
73, Dan, N7DE? ?
With respect, Dan, "need"
isn't an actionable or useful
concept, especially in QRP land.
I live on a sailboat and am
currently in Tampa Bay. With a
couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55
PM, Dan Eggers N7DE wrote:
20
w is -7 dB, and that is
too far down.? it is
getting close to -10 dB
down.? You need to be at
50 w, and that is only -3
dB down.? What I have used
for low cost has been an
MRF455 in an EB63A board
from Communications
Concepts, and it works
very well.
?
However,
the Chinese are selling a
100-w amplifier with a
heatsink that has had the
level set, and they also
sell a lowpass filter
board XDT LPF200 for 3 -
30 MHz at a reasonable
price that works very
well, so these days there
really isn't any reason to
"build your own"
amplifier.?
?
The
main thing I am saying is
that you need more power
so that you can be heard.?
I went through enough
Electrical Engineering
courses that I am now an
Electrical Engineer, but I
do not think I am going to
try design amplifiers from
scratch myself.
?
I
am very grateful for all
of the people who helped
produce the UBITX 6,
because I think that has
been the only low cost
real general coverage
transceiver that is out
there.? ? ? ? ? ? ?73,
Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET
is? IRFP150? And Not IRF150
, sorry for the typo.
I will edit at the end of
the video..
The FET i have used is
Harris IRFP 150
It works great with not much
heat at 35 V .
Regards
Sunil vu3sua
--
Jack, W8TEE
|
Re: Easy 20 Watts with any qrp
#bitx40
I think that is wonderful, and when you remember the name please send it to me.? I am at the point where I sort of forget things temporairly also, so that is no big deal.? Oh, well.? I am interested in a
lot of different technologies that all take up my time, but of course I intend to continue to stick with CW.? ? ? 73, Dan
??
toggle quoted message
Show quoted text
The digital voice mode that could possibly replace ssb is freedv. It is actually two things that work together.
First, the voice is converted into a stream of very few bits per second. A usual voice stream like that of telephone uses about 64,000 bits per second. Freedv codec reduces it to 700 bits per second. This is at the cost of reduced quality. However,
it is much better that SSB on 80 meters.
The second thing is an HF modem that can work at 700 bits per second. This is a weird one. On HF as signals bounce off the ionosphere and arrive at the rx antenna, you can have a situation where the same signal can arrive taking different paths
and hence at different times , overlapping itself. This reduces the number of times you can rapidly change the frequency of the signal. This is why FT8 works so well, it is so slow that fading, et al doesnt affect it. So, what the freedv modem does is that
it transmits a number of parallel ft8 like signals as separate tones within the same audio which when added up give you higher bandwidth. There is a very impressive name for it that escapes me now.
Our plan is to add freedv into the sbitx, making it the the first radio to support it natively.
- f
Gordon:
Either RadComm or Sprat had an article how students in England were fascinated by Morse code. When asked why, they replied that "voice" (SSB) didn't interest them because they could do that with their cell phone. But Morse was "better"
because their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
Well, for several years now we have observed some thing very fascinating among middle schoolers in our local school.
They are not interested at all in walkie-talkies
They are not interested at all in HF radios
Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they will grab onto and play with until you have to pull them away kicking and screaming with their parents,
Is a Morse code key!!!
At every school open house that we hold we now always provide multiple Morse code keys and it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of someone sending Morse code
We have two 6th graders in a very small school that are already doing about 10 words per minute. I sent 30 minutes worth of code to them two weeks ago?
It is astonishing the attraction that Morse code has for these middle schoolers
Meanwhile, across town, at the school devoted to future police and fire high schoolers, they have an extremely active contesting high school I am radio club and I am told that their best operator can do over 30 words per minute and they routinely make
hundreds and hundreds of contacts at voice and CW in contests. ?
Our local ham radio club would have a hard time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human nature is the same. And there are certain number of us who really love the auditory and tactile tickling that only Morse code gives¡. And by the way it is the first digital, the only digital that can be decoded by
the human brain without much else.? End it enjoys an order of magnitude or two advantage over voice In terms of threshold signal to noise ratio!!!?
On Mar 26, 2023, at 13:23, Dan Eggers N7DE <N7DE@...> wrote:
?
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain era.
Best wishes.? ? ? ?73, Dan
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster.? That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe you use solar cells and power
conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
--
Jack, W8TEE
|
Re: Easy 20 Watts with any qrp
#bitx40
The digital voice mode that could possibly replace ssb is freedv. It is actually two things that work together. First, the voice is converted into a stream of very few bits per second. A usual voice stream like that of telephone uses about 64,000 bits per second. Freedv codec reduces it to 700 bits per second. This is at the cost of reduced quality. However, it is much better that SSB on 80 meters. The second thing is an HF modem that can work at 700 bits per second. This is a weird one. On HF as signals bounce off the ionosphere and arrive at the rx antenna, you can have a situation where the same signal can arrive taking different paths and hence at different times , overlapping itself. This reduces the number of times you can rapidly change the frequency of the signal. This is why FT8 works so well, it is so slow that fading, et al doesnt affect it. So, what the freedv modem does is that it transmits a number of parallel ft8 like signals as separate tones within the same audio which when added up give you higher bandwidth. There is a very impressive name for it that escapes me now. Our plan is to add freedv into the sbitx, making it the the first radio to support it natively. - f
Gordon:
Either RadComm or Sprat had an article how students in England were fascinated by Morse code. When asked why, they replied that "voice" (SSB) didn't interest them because they could do that with their cell phone. But Morse was "better" because their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
Well, for several years now we have observed some thing very fascinating among middle schoolers in our local school.
They are not interested at all in walkie-talkies They are not interested at all in HF radios Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they will grab onto and play with until you have to pull them away kicking and screaming with their parents,
Is a Morse code key!!!
At every school open house that we hold we now always provide multiple Morse code keys and it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of someone sending Morse code
We have two 6th graders in a very small school that are already doing about 10 words per minute. I sent 30 minutes worth of code to them two weeks ago?
It is astonishing the attraction that Morse code has for these middle schoolers
Meanwhile, across town, at the school devoted to future police and fire high schoolers, they have an extremely active contesting high school I am radio club and I am told that their best operator can do over 30 words per minute and they routinely make hundreds and hundreds of contacts at voice and CW in contests. ?
Our local ham radio club would have a hard time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human nature is the same. And there are certain number of us who really love the auditory and tactile tickling that only Morse code gives¡. And by the way it is the first digital, the only digital that can be decoded by the human brain without much else.? End it enjoys an order of magnitude or two advantage over voice In terms of threshold signal to noise ratio!!!? On Mar 26, 2023, at 13:23, Dan Eggers N7DE <N7DE@...> wrote:
?
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain
era.
Best wishes.? ? ? ?73, Dan
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster.? That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe
you use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
--
Jack, W8TEE
|
If it's not affecting performance now, I doubt it would affect anything mostly by situating the board within a specific build or position. Good luck on the project!? 
|
Re: Easy 20 Watts with any qrp
#bitx40
Gordon:
Either RadComm or Sprat had an article how students in England were fascinated by Morse code. When asked why, they replied that "voice" (SSB) didn't interest them because they could do that with their cell phone. But Morse was "better" because their parents couldn't understand what was being said.
Any port in a storm...
Jack, W8TEE
On Sunday, March 26, 2023 at 01:55:50 PM EDT, Gordon Gibby <docvacuumtubes@...> wrote:
Well, for several years now we have observed some thing very fascinating among middle schoolers in our local school.
They are not interested at all in walkie-talkies They are not interested at all in HF radios Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they will grab onto and play with until you have to pull them away kicking and screaming with their parents,
Is a Morse code key!!!
At every school open house that we hold we now always provide multiple Morse code keys and it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of someone sending Morse code
We have two 6th graders in a very small school that are already doing about 10 words per minute. I sent 30 minutes worth of code to them two weeks ago?
It is astonishing the attraction that Morse code has for these middle schoolers
Meanwhile, across town, at the school devoted to future police and fire high schoolers, they have an extremely active contesting high school I am radio club and I am told that their best operator can do over 30 words per minute and they routinely make hundreds and hundreds of contacts at voice and CW in contests. ?
Our local ham radio club would have a hard time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human nature is the same. And there are certain number of us who really love the auditory and tactile tickling that only Morse code gives¡. And by the way it is the first digital, the only digital that can be decoded by the human brain without much else. ?End it enjoys an order of magnitude or two advantage over voice In terms of threshold signal to noise ratio!!!? On Mar 26, 2023, at 13:23, Dan Eggers N7DE <N7DE@...> wrote:
?
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain
era.
Best wishes.? ? ? ?73, Dan
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe
you use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
-- Jack, W8TEE
|
I am building a V5 into a pelican style case for POTA activations.? My concern is that while inspecting the board, I noticed that one of the RV3 pot nearest the finals is slightly twisted or skewed.? ?Is this likely to cause an issue?? As far as I can tell I shouldn't need to adjust it as I am getting proper output (I'll know more once I get it on the air).? If its fine, I'll leave it but I don't want it to cause any problems.
Thanks??
|
Re: Easy 20 Watts with any qrp
#bitx40
Well, for several years now we have observed some thing very fascinating among middle schoolers in our local school.
They are not interested at all in walkie-talkies They are not interested at all in HF radios Don¡¯t even get me thinking about digital.
What they absolutely go crazy over, what they will grab onto and play with until you have to pull them away kicking and screaming with their parents,
Is a Morse code key!!!
At every school open house that we hold we now always provide multiple Morse code keys and it is a big draw.
We will provide them at this year¡®s field day
The news media always want a picture of someone sending Morse code
We have two 6th graders in a very small school that are already doing about 10 words per minute. I sent 30 minutes worth of code to them two weeks ago?
It is astonishing the attraction that Morse code has for these middle schoolers
Meanwhile, across town, at the school devoted to future police and fire high schoolers, they have an extremely active contesting high school I am radio club and I am told that their best operator can do over 30 words per minute and they routinely make hundreds and hundreds of contacts at voice and CW in contests. ?
Our local ham radio club would have a hard time beating them!!!!
So I wouldn¡¯t quite give up yet. ?human nature is the same. And there are certain number of us who really love the auditory and tactile tickling that only Morse code gives¡. And by the way it is the first digital, the only digital that can be decoded by the human brain without much else. ?End it enjoys an order of magnitude or two advantage over voice In terms of threshold signal to noise ratio!!!?
toggle quoted message
Show quoted text
On Mar 26, 2023, at 13:23, Dan Eggers N7DE <N7DE@...> wrote:
?
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain
era.
Best wishes.? ? ? ?73, Dan
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe
you use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
Hi All, I finally found some time to try fixing this issue. I moved the LED and photoresistor out of the board and over the AUDIO socket. Now there is no long cables connecting the photoresistor to the socket and the hissing sound disappeared.   Another changes I did:
- Add an LC filter using a VK200 choke for the power supply cable from ubitx to the board
- Add shielded cables for all the audio signals, connecting the shield to the metal enclosure.
I still hear a hissing sound when enabling the band pass filter, the culprit seems to be LM567 that I use for tone detection. If I change the local oscillator frequency in LM567 the hissing tone changes pitch. The sound vanishes if I disconnect the supply from the IC. I will try an LC filter to isolate LM567 power supply to the rest of the board. Anyone has suggestions to get rid of this interference? This was probably also causing the hissing sound when the photoresistor was installed in the board. Thanks Agustin - LU2HES
|
Re: Easy 20 Watts with any qrp
#bitx40
Thank you?for the information.? I see you and I are both CW old timers.? So far we have lost about half of the CW people without any real replacements coming along, but you and I came along during a certain
era.
Best wishes.? ? ? ?73, Dan
toggle quoted message
Show quoted text
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe
you use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
Eventually there will be something that replaces analog single side band voice. But it¡¯s not yet here. ? And I think I have been doing CW for 55 years or more. ?
That¡¯s my thought
Gordon Kx4z?
toggle quoted message
Show quoted text
On Mar 26, 2023, at 11:51, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe you
use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
I need help with reloading the V6 soft ware. If you can help me, please call 907-262-7699.
i have read numerous times the instructions on the web and have attempted to follow them
with no success. I am running MInt. Any help would be appreciated.
|
Re: Easy 20 Watts with any qrp
#bitx40
I have been sending Morse code now for 57 years, and I will just continue to send Morse code, but since you seem to be very knowledgeable is there a digital voice modulation system that will eventually replace SSB?
Thank you.? ? ? ? ? 73, Dan, N7DE?
toggle quoted message
Show quoted text
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe you
use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
When you are running mm you can do some things that other people cannot do.? I run mobile CW when I am traveling across?the country, and that works very well for me.
I have a lot of different interests, and right now I am trying to get everyone to tie the two tubes from the inside unit to the outside unit of their air?conditioners together to make things operate more efficiently.? You may
not need air conditioning when you are running mm, but it makes things more efficient for people with air condition systems like people in Texas.? I am in Edinburg, TX - not too far from Brownsville, TX, but I would like to go home to Seattle.? I will be running
mobile CW most of the way.
? ? ? ? ?73, Dan, N7DE
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Sorry...let's try this again. I hate working on a phone.
Dan - I live on a sail boat. A couple of meters of tinned braid tossed over the side, a shortened 40 meter vertical, and 8 Watts from my uBITX V6 is all I need for a reliable Winlink connection across the Gulf of Mexico to Brownsville, TX for email and wind
data. I know for a fact that I don't "need" 20W or even your suggested 50 W to do what I need to get done.
No sir - everybody does not "need" 50 or more Watts.? You do you - enjoy your QRO gear!?
There is no "reason" to build our own gear? There is no "reason" for the Amateur service either, I guess. That's not going to stop me from building, or continuing to learn how to build amplifiers. That's precisely why I got this ticket, after all.
Best, Andy, KG5RKP/MM
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
Single side band typically requires a 10 DB signal to noise ratio for useful communications in a disaster. ?That is, the efficient transfer of information
My contrast, using the same base noise in that bandwidth, data communications of moderate speed can tolerate SNR into low single digits, and still move efficient communications far faster than voice
Low data rate redundant digital communications can tolerate signal to noise ratios a couple orders of magnitude lower SNR
These comparisons are widely available
It¡¯s no secret why people who are very involved in the (voice) national traffic system often have kilowatt amplifiers. ?
And people who are into JS8 ?don¡¯t need them
So there are different requirements for different parts of our hobby
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On Mar 26, 2023, at 11:33, Dan Eggers N7DE <N7DE@...> wrote:
?
I used 20 watts for a long time, and I have had a number of people refuse to talk to me, because my signal was too week, so more power is needed.? I have written a booklet about solar cells, and maybe you
use solar cells and power conversion, and that is also a very interesting area, but I also want to be able to talk to people.
? ? ? 73, Dan, N7DE? ?
With respect, Dan, "need" isn't an actionable or useful concept, especially in QRP land.
I live on a sailboat and am currently in Tampa Bay. With a couple of meters of tinn
On Sat, Mar 25, 2023 at 01:55 PM, Dan Eggers N7DE wrote:
20 w is -7 dB, and that is too far down.? it is getting close to -10 dB down.? You need to be at 50 w, and that is only -3 dB down.? What I have used for low cost has been an MRF455 in an EB63A board from Communications Concepts,
and it works very well.
?
However, the Chinese are selling a 100-w amplifier with a heatsink that has had the level set, and they also sell a lowpass filter board XDT LPF200 for 3 - 30 MHz at a reasonable price that works very well, so these days there really
isn't any reason to "build your own" amplifier.?
?
The main thing I am saying is that you need more power so that you can be heard.? I went through enough Electrical Engineering courses that I am now an Electrical Engineer, but I do not think I am going to try design amplifiers
from scratch myself.
?
I am very grateful for all of the people who helped produce the UBITX 6, because I think that has been the only low cost real general coverage transceiver that is out there.? ? ? ? ? ? ?73, Dan, N7DE
?
Hi Ted
Thanks. Incidentally the FET is? IRFP150? And Not IRF150 , sorry for the typo.
I will edit at the end of the video..
The FET i have used is Harris IRFP 150
It works great with not much heat at 35 V .
Regards
Sunil vu3sua
|
Sunil Lakhani
Ted
Agustin - LU2HES