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Easy 20 Watts with any qrp
#bitx40
IMD? power is ok but what is IMD level? On Thu, Mar 23, 2023 at 7:13?AM Sunil Lakhani <vu3sua@...> wrote: Hi Friends? --
Md Sofiullah
Assist. Manager
Pulse e Technologies Pvt. Ltd,
222, Phase-IV, Udyog Vihar,
Gurgaon-122015, Haryana
Cell: +91 9811842473
???????? +91 9654698929 |
Dan Eggers N7DE
开云体育
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
From: [email protected] <[email protected]> on behalf of Sunil Lakhani <vu3sua@...>
Sent: Friday, March 24, 2023 1:19 AM To: [email protected] <[email protected]> Subject: Re: [BITX20] Easy 20 Watts with any qrp #bit40 ?
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 |
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 |
Dan Eggers N7DE
开云体育
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
From: [email protected] <[email protected]> on behalf of JerryP <jponko@...>
Sent: Saturday, March 25, 2023 1:07 PM To: [email protected] <[email protected]> Subject: Re: [BITX20] 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 |
开云体育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
From: [email protected] <[email protected]> on behalf of JerryP <jponko@...>
Sent: Saturday, March 25, 2023 1:07 PM
To: [email protected] <[email protected]>
Subject: Re: [BITX20] 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