Re: Elecraft 70cm transverter, K3 and repeater access tones?
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Re: Elecraft 70cm transverter, K3 and repeater access tones?
 
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James,
The XV432 itself *does* cover the full 70-cm range. If you use it with a rig that covers 28-32 MHz, you'll have this capability. But the K3 only covers 28-30 MHz. 73, Wayne N6KR >> Thanks for the information. I didn't realize that the XV432 didn't >> cover >> the whole 70cm band. This is good to know, as I intended to use the >> transverter to communicate with local 440 machines. I suppose it >> would be >> better for me then to go with the XV144, or just buy a 2m/440 base >> instead. >> >> 73, >> James KC2UEE --- http://www.elecraft.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 |
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This is not really a K3 issue, it is the same for all transverters. HF radios and transverters don't often cover the entire 70cms band almost never the entire 23cms band.
70cms in Europe covers 10MHz of bandwidth, from 430 to 440 MHz. In the USA I understand it is more. A 2 MHz band segment 432-434 MHz will give you the SSB and some of the FM section used in Europe, but it will not cover the satellite allocation or repeaters. The Microwave Modules range of transverters used to cover this with a dual LO allowing a 1.6MHz offset for our repeater shift. There may be some merit in using 50MHz for the IF, it should be fairly easy to redesign the XV432 for this by changing components. Perhaps one day Elecraft may offer this as an option - along with K3 colour co-ordination and complementary K3 embossed biscuits at Dayton. Mike
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Re: Elecraft 70cm transverter, K3 and repeater access tones?
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In reply to this post by wayne burdick
Could not the K3 be transmit-enabled up to 32MHz? Are the bandpass filters too narrow to permit this? It seems like potentially a very easy solution.
Julian, G4ILO. K2 #392 K3 #222 KX3 #110
* G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html |
Re: Elecraft 70cm transverter, K3 and repeater access tones?
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There are switched bandpass filters prior to the 10w PA stage, which are
also in circuit before the transverter output. I expect that the 28 to 30MHz filter would not be suitable right up to 32MHz. So I guess an extension of transmit capability to 32MHz would not be on the cards. Regards John G4ZTR -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Julian, G4ILO Sent: 17 February 2009 09:04 To: [hidden email] Subject: Re: [Elecraft] Elecraft 70cm transverter, K3 and repeater access tones? wayne burdick wrote: > > The XV432 itself *does* cover the full 70-cm range. If you use it with > a rig that covers 28-32 MHz, you'll have this capability. But the K3 > only covers 28-30 MHz. > Could not the K3 be transmit-enabled up to 32MHz? Are the bandpass filters too narrow to permit this? It seems like potentially a very easy solution. ----- Julian, G4ILO. K2 #392 K3 #222. http://www.g4ilo.com/ G4ILO's Shack http://www.g4ilo.com/blog.html G4ILO's Blog http://www.g4ilo.com/kcomm.html KComm for Elecraft K2 and K3 -- View this message in context: http://n2.nabble.com/Re%3A-Elecraft-70cm-transverter%2C-K3-and-repeater-acce ss--tones--tp2338664p2339797.html Sent from the Elecraft mailing list archive at Nabble.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 __________ Information from ESET NOD32 Antivirus, version of virus signature database 3857 (20090216) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __________ Information from ESET NOD32 Antivirus, version of virus signature database 3860 (20090217) __________ 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 |
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In reply to this post by wayne burdick
While I don't have a 432 Elecraft transverter, I have had a lot of experience with DEM transverters and K3's over the last year. If you change the crystal in the transverter to use 26 MHz for 432 then 30 MHz would be 436 and this works well with a couple of caveates. The bandpass filters start to cut off pretty sharply around 27 MHz and you will find the rx is down about 6 db, mostly not a problem since most transverters have ample gain. On the transmit side, I have found the output is reduced to about -6 dbm and isn't as adjustable as it is at 28 MHz, probably ALC action with reduced output from the bandpass filters. I have used it and it works well, you just have to play with the levels and as you go up in frequency, you have to watch that you don't overdrive the transverter. DEM offers a crystal that allows their transverter to cover 435 with a 28 MHz IF, this equates to a 25 MHZ IF for 432 and the 12m bandpass should work well for this but once again, as you go up, the bandpass will be dropping until you reach around 27 MHz.
I have considered re-tuning the 10m filters down to give flatter response at 26MHz giving away 28.8 and up which I never use anyway but haven't decided which way to go. Since the FM band in the US is 440 to 450, it's a waste since nothing you do is ever going to give you 20 MHz of bandwidth. I just keep a 70cm FM transceiver around and just use the K3 for weak signal work around 432.
Hope this helps.
Terry - W8ZN
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In reply to this post by AD6XY
Hi Mike & all,
> There may be some merit in using 50MHz for the IF, it should be fairly easy > to redesign the XV432 for this by changing components. Actually what I would love to see is a "transverter band" IF which has "no" potential conflict with any of the ham bands e.g. 30MHz to 48MHz with a 0dBm TX-signal. I doubt the K3 hardware can do this at present but maybe one day the K3+ ;-) vy 73 de toby ______________________________________________________________ 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 |
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