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Re: Easy 20 Watts with any qrp
#bitx40
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
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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
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
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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
No.? I was not aware of that.? I am also licensed as a Broadcast Engineer, and we have a 100,000 watt FM station here in Pharr, TX? KVMV.? What I had in mind was one sideband without the other sideband and
the carrier.? However, if you can do one, then I think you can do the other also.? I run CW on 40 m and 20 m to an off center fed dipole, so I would want more than 80 & 40, but I am real glad to know that there is someone out there doing class D amplifiers.
? ? ? ? ? 73, Dan, N7DE
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Speaking of class D amplifiers, are you aware of K7DDY's legal-limit AM transmitter that uses a class D amplifier?
|
He offers 160/80 meter and 80/40 meter models.
Yes, I realize that AM is the polar-opposite of CW...
Ken, N2VIP
On Mar 25, 2023, at 16:16, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue sending, but I do have one request.? I would like to see you, and others, work on making a transceiver that does not require any
lowpass filters.? I would like you generate a Single Side Band (SSB) output digitally at full power, and that would preobably involve at least 100 MHz, or more, at full power.? That should only require one filter say at 30 MHz.? That would be similar to the
way that they do Class D amplification of audio.? I think that is the next step in Amateur Radio RF.
? ? ? ?73, Dan, N7DE
Some people like to experiment and build stuff from scratch or buy a kit and experiment with that so that they can learn something. Not everyone wants to use 100 Watt transmitters. So there is a reason to build your own. I'm an EE and I don't buy commercial
HF HAM equipment because I can build it myself or buy something like Farhan's sbitx kit to experiment with. I can imagine that someday, discreet HF transistors and other parts are no longer being made and all HAMs end up as appliance operators. Ugh!. Until
then, I can enjoy building stuff just for the joy it.
--
Jerry Ponko, AC9NM
Hi Rafael, many thanks for the suggestion. I will have a look..
Art G3XNE
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From: [email protected] on behalf of Rafael Diniz
Sent: Friday, March 24, 2023 07:29
To: [email protected]
Subject: Re: [BITX20] uBITX V6
Hi Art,
Getting the T/R output from the Arduino does not work for you? If I
remember by heart, it is the first pin on the Raduino connector (to the
radio).
Rafael
On 3/24/23 01:59, art wrote:
> This little wonder? keeps me busy,, Many thanks all with my query on
> ''pin 16 ''. On looking? closer I discovered I had the wrong?
> connector schematic anyway, so that was
> my train of thought ruined.? On to more !! Can you tell me if I can
> pick up a PTT? connection somewhere on the pcb? fairly easily. Am not
> using the mic/cw front panel connector at the moment, this is an
> additional? project being worked on... Polarity of the current PTT ??
> .. Thanks in advance..
>
> Art? G3XNE
>
|
Re: Easy 20 Watts with any qrp
#bitx40
Speaking of class D amplifiers, are you aware of K7DDY's legal-limit AM transmitter that uses a class D amplifier?
|
He offers 160/80 meter and 80/40 meter models.
Yes, I realize that AM is the polar-opposite of CW...
toggle quoted message
Show quoted text
On Mar 25, 2023, at 16:16, Dan Eggers N7DE <N7DE@...> wrote:
?
I have been sending Morse code now for 57 years, and I will just continue sending, but I do have one request.? I would like to see you, and others, work on making a transceiver that does not require any
lowpass filters.? I would like you generate a Single Side Band (SSB) output digitally at full power, and that would preobably involve at least 100 MHz, or more, at full power.? That should only require one filter say at 30 MHz.? That would be similar to the
way that they do Class D amplification of audio.? I think that is the next step in Amateur Radio RF.
? ? ? ?73, Dan, N7DE
Some people like to experiment and build stuff from scratch or buy a kit and experiment with that so that they can learn something. Not everyone wants to use 100 Watt transmitters. So there is a reason to build your own. I'm an EE and I don't buy commercial
HF HAM equipment because I can build it myself or buy something like Farhan's sbitx kit to experiment with. I can imagine that someday, discreet HF transistors and other parts are no longer being made and all HAMs end up as appliance operators. Ugh!. Until
then, I can enjoy building stuff just for the joy it.
--
Jerry Ponko, AC9NM
Re: Easy 20 Watts with any qrp
#bitx40
I have been sending Morse code now for 57 years, and I will just continue sending, but I do have one request.? I would like to see you, and others, work on making a transceiver that does not require any
lowpass filters.? I would like you generate a Single Side Band (SSB) output digitally at full power, and that would preobably involve at least 100 MHz, or more, at full power.? That should only require one filter say at 30 MHz.? That would be similar to the
way that they do Class D amplification of audio.? I think that is the next step in Amateur Radio RF.
? ? ? ?73, Dan, N7DE
toggle quoted message
Show quoted text
Some people like to experiment and build stuff from scratch or buy a kit and experiment with that so that they can learn something. Not everyone wants to use 100 Watt transmitters. So there is a reason to build your own. I'm an EE and I don't buy commercial
HF HAM equipment because I can build it myself or buy something like Farhan's sbitx kit to experiment with. I can imagine that someday, discreet HF transistors and other parts are no longer being made and all HAMs end up as appliance operators. Ugh!. Until
then, I can enjoy building stuff just for the joy it.
--
Jerry Ponko, AC9NM
|
Re: Easy 20 Watts with any qrp
#bitx40
Some people like to experiment and build stuff from scratch or buy a kit and experiment with that so that they can learn something. Not everyone wants to use 100 Watt transmitters. So there is a reason to build your own. I'm an EE and I don't buy commercial HF HAM equipment because I can build it myself or buy something like Farhan's sbitx kit to experiment with. I can imagine that someday, discreet HF transistors and other parts are no longer being made and all HAMs end up as appliance operators. Ugh!. Until then, I can enjoy building stuff just for the joy it.
--
Jerry Ponko, AC9NM
|
Re: Easy 20 Watts with any qrp
#bitx40
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
toggle quoted message
Show quoted text
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: Distorted mic audio on TX through speaker V3
Your probably picking up audio through the K3 relay.? M1/M2 scheme.
Fix was the Q74 2N7000 audio shunt from V4 onwards.
Look at the v4,v5,v6 schematic and copy that.? R70 value also changed to 1k.
Rgds,
Gary
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Distorted mic audio on TX through speaker V3
Hi,?
I have a V3 in a Sunil case. I¡¯m getting very bad audio feedback through both internal and external speakers when transmitting SSB. ?I¡¯ve tried several mics, twisting cables, grounding everything, but it¡¯s no better¡.. I¡¯ve even installed a 0.1uf cap across the volume pot. I don¡¯t have an audio amp installed nor AGC board so they can¡¯t be the problem either.?
Any suggestions as it¡¯s driving me mad!?
Regards
Carl M0CLS?
|
Re: Easy 20 Watts with any qrp
#bitx40
With a gate input capacitance of 2800pf it must be bear to drive.
I've run IRF510s at 24V and for HF 25watts is easy for only one device
with two push-pull 50-55w is a safe limit..
--
Allison
------------------
Please use the forum, offline and private will go to bit bucket.
|
David, ? The ND6T AGC with board designed by KitProjects has been released. Files are here and the build is reasonably quick. Gerbers and docs are at the link. ? ? /g/BITX20/files/Kit-Projects
73, Andy
On Sat, Mar 18, 2023 at 02:29 PM, David Posthuma wrote:
Most all AGC circuits are either designed for the earlier versions or are no longer in production. Is there any AGC circuit designed specific to version 6 of uBitx that uses the 50k ohm volume pot in stead of the 10k ohm pot?
thanks,
David, W8US
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Re: Easy 20 Watts with any qrp
#bitx40
"The FET i have used is Harris IRFP 150 It works great with not much heat at 35 V ."
Thanks.? I'll look for that.
-Ted
|
Art,
HFSignals provides schematics, source code and more from?
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Re: Easy 20 Watts with any qrp
#bitx40
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Re: Easy 20 Watts with any qrp
#bitx40
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Re: Easy 20 Watts with any qrp
#bitx40
Hi Sof
I have not done that analysis . maybe some other guys can dive deeper.
Regards
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
Hi Doug
The easy bitx kit version 1 and version 2 are ready. By this weekend we shall update the availability .
Also we are listing the Airpal 2 band tcvr.
Thanks
Sunil vu3sua
|
Re: Easy 20 Watts with any qrp
#bitx40
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 Art,
Getting the T/R output from the Arduino does not work for you? If I remember by heart, it is the first pin on the Raduino connector (to the radio).
Rafael
toggle quoted message
Show quoted text
On 3/24/23 01:59, art wrote: This little wonder? keeps me busy,, Many thanks all with my query on ''pin 16 ''. On looking? closer I discovered I had the wrong? connector schematic anyway, so that was
my train of thought ruined.? On to more !! Can you tell me if I can pick up a PTT? connection somewhere on the pcb? fairly easily. Am not using the mic/cw front panel connector at the moment, this is an additional? project being worked on... Polarity of the current PTT ?? .. Thanks in advance..
Art? G3XNE
|
JerryP
Ted
Sunil Lakhani