What is the better solution for adding 2 meter capability to the K3, the new internal K144XV or the XV144 transverter. I see that the power output of the K144XV is 10 watts and that the power output of the transverter is about 20 to 25 watts. Let's assume I would want a 100 watt PA, does it make a difference on whether I have 10 watts drive or 25 watts drive? Since I have not looked at any such linear amplifier I am not sure what the drive requirement would be.
I have not exhaustively read all the documentation available on these two but I was curious if there were any "stand out" reasons for choosing one over the other. Thanks, phil, K7PEH ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
It is really up to you but a 100W VHF amplifier should not need more than 10W of drive, typically much less. A 300W will amplifier perhaps need more drive. Of course the output will be cleaner if under run, so a 25W amplifier running 10W ought to be cleaner than when running 25W.
You only really need 25W of drive if you are using a large triode and hoping for 1500W, indeed perhaps more like 50W would be appropriate. For a 300w solid state PA like the reccomended by me Tokyo Hi Power HL-350Vdx it makes no difference. It has 10W, 25W and 50W input settings. Mike
|
In reply to this post by Phil Hystad
Hello Phil,
Apart from technicial specifications, it will also depend on whether you will use the transverter with other rigs. If your answer is yes, you then need the XV144. One more thing, XV144 is supposed to work at 10 watt if under full duty cycle i.e. FM mode. In fact, when XV144 works under FM mode, it is extremely hot. cheers, Johnny Siu VR2XMC ________________________________ 寄件人﹕ Phil Hystad <[hidden email]> 收件人﹕ Elecraft <[hidden email]> 傳送日期﹕ 2009/12/8 (二) 11:21:10 AM 主題: [Elecraft] K3 2 meter capability: internal K144XV or XV144 transverter? What is the better solution for adding 2 meter capability to the K3, the new internal K144XV or the XV144 transverter. I see that the power output of the K144XV is 10 watts and that the power output of the transverter is about 20 to 25 watts. Let's assume I would want a 100 watt PA, does it make a difference on whether I have 10 watts drive or 25 watts drive? Since I have not looked at any such linear amplifier I am not sure what the drive requirement would be. I have not exhaustively read all the documentation available on these two but I was curious if there were any "stand out" reasons for choosing one over the other. Thanks, phil, K7PEH Yahoo!香港提供網上安全攻略,教你如何防範黑客! 請前往 http://hk.promo.yahoo.com/security/ 了解更多! ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Johnny -
The Mitsubishi RA30H1317M module used in the XV144 is supposedly rated at 30W at 135-175MHz. Having said that my XV144 seems to trip out if I run it more than about 5W on FM. 73 David G4DMP [Top posted as recommended, but I don't like it!] In a recent message, Johnny Siu <[hidden email]> wrote ... >One more thing, XV144 is supposed to work at 10 watt if under full duty >cycle i.e. FM mode. In fact, when XV144 works under FM mode, it is >extremely hot. -- David G4DMP Leeds, England, UK ------ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
David
The secret with these RA Mitsubishi modules is getting the heat away, and they're not very efficient at all. The earlier M series were a little better (I notice that's what shows on Elecraft's web site pictures but no doubt they have had to upgrade when stocks ran out). Looks like the internal transverter runs discrete components ? Can't quite see enough in the pictures to be sure. Regards John G4ZTR -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of David Pratt Sent: 08 December 2009 11:14 To: Johnny Siu Cc: Elecraft Subject: [Elecraft] K144XV or XV144 transverter? Johnny - The Mitsubishi RA30H1317M module used in the XV144 is supposedly rated at 30W at 135-175MHz. Having said that my XV144 seems to trip out if I run it more than about 5W on FM. 73 David G4DMP [Top posted as recommended, but I don't like it!] In a recent message, Johnny Siu <[hidden email]> wrote ... >One more thing, XV144 is supposed to work at 10 watt if under full duty >cycle i.e. FM mode. In fact, when XV144 works under FM mode, it is >extremely hot. -- David G4DMP Leeds, England, UK ------ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __________ Information from ESET NOD32 Antivirus, version of virus signature database 4669 (20091208) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __________ Information from ESET NOD32 Antivirus, version of virus signature database 4669 (20091208) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
In reply to this post by AD6XY
I totally agree with this.
I've too noticed when running the XV144 at more than 10/15 W the xverter case get pretty hot. The Elecraft guys btw are well known to be conservative about component choice, keeping well within the safe limits. On the other hand, just to keep things less hot I'vee added a small cpu fan over the top holes (the ones over the attenuator resistors) to drag out the hot air. Since then the case has been a lot less warm even at full output for some minutes. To avoide excessive noise from the fan I've connected the Voltage supply for the fan at the 12T point, so it runs only when on tx. These are my cents on the matter... :-) 73 de Giulio IW3HVB AD6XY ha scritto: Snip > Of course the output will be cleaner if under run, so a 25W amplifier > running 10W ought to be cleaner than when running 25W. > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Hello Giulio,
The XV144 is not cheap. It is a great waste if it only uses for SSB/CW. However, it is really hot even run at 10W FM. Yes, I do the same and add a small CPU fan. Where do you take the 12T point? cheers, Johnny VR2XMC ----- 郵件原件 ---- 寄件人﹕ Giulio Pico - IW3HVB <[hidden email]> 副本(CC) [hidden email] 傳送日期﹕ 2009/12/8 (二) 7:31:13 PM 主題: Re: [Elecraft] K3 2 meter capability: internal K144XV or XV144 transverter? I totally agree with this. I've too noticed when running the XV144 at more than 10/15 W the xverter case get pretty hot. The Elecraft guys btw are well known to be conservative about component choice, keeping well within the safe limits. On the other hand, just to keep things less hot I'vee added a small cpu fan over the top holes (the ones over the attenuator resistors) to drag out the hot air. Since then the case has been a lot less warm even at full output for some minutes. To avoide excessive noise from the fan I've connected the Voltage supply for the fan at the 12T point, so it runs only when on tx. These are my cents on the matter... :-) 73 de Giulio IW3HVB AD6XY ha scritto: Snip > Of course the output will be cleaner if under run, so a 25W amplifier > running 10W ought to be cleaner than when running 25W. > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Yahoo!香港提供網上安全攻略,教你如何防範黑客! 請前往 http://hk.promo.yahoo.com/security/ 了解更多! ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
In reply to this post by AD6XY
My W6UOV (W6PO) designed 8877 two-meter amp needed more like 100 W drive to deliver 1500 out.
In the original article, Ham Radio Magazine, Aug 1971, pp 22-28, he listed operating parameters. He claimed 13.8 dB gain at 1 KW out. I never saw that at 1500 W out. A good rule of thumb is gain = 10 dB and then your driver isn't sweating and you're not worried about every fraction of a dB coax loss, etc. --- On Tue, 12/8/09, AD6XY <[hidden email]> wrote: > > You only really need 25W of drive if you are using a large > triode and hoping > for 1500W, indeed perhaps more like 50W would be > appropriate. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Free forum by Nabble | Edit this page |