[Elecraft] K3 and XV144...
I'm mainly going to use my K3 for 6m and 2m using my recently built XV144. However, in terms of optimising my station's performance (in this case, thinking of removing the MMIC after the PHEMT front-end to improve the XV144's dynamic range) I'm reliant on doing the maths based on other people's lab tests (like many I'm sure, I just don't have the lab gear!). The XV144 gain/NF plot on the website shows about 28dB gain and 0.6 dB NF - is this typical? Also the latest K3 specs show the MDS as being -136dBm...but is this pre-amp On or Off? At the moment I reckon the XV144 won't need the second stage of front-end gain, especially if the K3 has anything close to a 16dB NF at 28 MHzbut I'd appreciate some second opinions... No rush, I'm in the second production run :-) Regards Paul M0CVX (and AC5NO) - Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 and XV144
Hello All, Does the K3 (with KXV3 interface) and XV144 combination transmit from 145.8 to 146.0MHz for use with OSCAR satellites? Since 10m only goes up to 29.7MHz, it's not high enough with a transverter using a 116MHz LO. Further to the point, can the K3 transmit via its KXV3 interface from 48 to 54MHz? This would allow using a transverter with a 384MHz LO to cover 432 to 438MHz for use with all OSCAR satellites. I suspect it could be yet another firmware change so that it can transmit outside of the amateur bands at the very low levels of the transverter interface and not through the main amplifiers. I don't know if anyone has tried using their K3 with the XV144 or XV432 transverters yet. 73 de David VK5DG (when the new tower is up and antenna installed, then I'll get on the queue). ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 and XV144 video
We've put a video of our last setup on the local club website. There is our 2 log loop yagi stack and my K3 and XV144 xverter on a nice display, showing a beacon 500 Km away from our loc. Needless to say that the rig is working fine, despite of some strange behaviour of the XV144 not always recognized by the K3 at the power up. http://www.arimarcon.it/FILMATI/FILMATI.htm# The video is the first one Down on the page you can also find a small video taken during the IOTA contest where I was still using my K2. 73 de Giulio IW3HVB ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 and XV144 strange behaviour
I noticed a strange behaviour during the last IARU VHF Contest last weekend. With our team we managed to have a first field test of the rig coming for our experience with the K2/xv144 MHz combination the expectations were high. The setup was composed by the K3 and a XV144 transverter, plus a Power amplifier, a preamplifier at the antenna (with some 30 mt of 1/2" cellflex line) and two stacked 19 elements Log Loop Yagis. The switching sequence was controled by an external sequencer drived by a foot pedal. On the receiving side the combo was wonderful, the dynamic range allowed us to manage very well in the pretty crowded 2 mt band. But we had some troubles mainly on TX. Let say that our P.A. needs to be drived with circa 7/10 Watts at maximum (depending on the mode, SSB or CW). It's made from 2 x 4CX250B in push-pull configuration. So I tuned the transverter to go from a range of 1 W (with -10 dBm drive from the KXV3 module) to a mazimum of 10 W (with 0 dBm of drive). Things have worked pretty smoothly most of the time, but on a few occasions, we noticed a sudden loss of output power from the transverter (and from the P.A. of course). Turning the K3 off and on again the transverter didn't power up. The XV144 label on the front panel flashed for a brief moment and then stayed off. Changing band to HF and back again on 144 MHz (TRV1) and the XV144 module powered up again. Not always on the first try. Once powered up most of the times the output power was correct, but occasionally we had to do the procedure three or four times before coming back to normal functioning. Any clues of the reasons of this behaviour??? 73 de Giulio IW3HVB ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 and XV144 strange behaviour
Before you ask... Firmware Revisions: MCU 2.34; DSP 1.89. 73 de Giulio IW3HVB. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 and XV144 strange behaviour
On receive we had persistent problems with people using lesser receivers and similar transmit power not being able to copy us because of QRM. DLs especially. We heard many very strong signals but none excessively wide. We also had system problems though not the same, or at least the same but partly fixed. In our case the 9-way D connector was at fault, unless fully screwed in it was found to not be making a good contact. Fully screwing it in fixed that of course, nothing to do with the K3. Our main K3 related problem was the inconsistent power output. We were also using a pair of 4CX250Bs, parallel rather than push pull. To avoid over drive splatter, the amplifier trips out if any significant grid current occurs. The power spikes I have noted before made tuning up the drive with the PA on impossible. The correct drive was set, in incremental steps with the spike dealt with by keying with the PA off for the first transmission, then enabling the PA and seeing if the drive was sufficient. Once set the power would not stay fixed, it would sometimes drop by maybe 2-3 dB. Just adjusting the power one step up or down brought it back but with the usual initial spike that would on occasion trip the amplifier protection. After a couple of overs the power would drop back again. While setting up we also did some transmit cleanliness checks with local stations. The K3 + XV144 at about 7W output driving the pair of 4CX250Bs was reported to be exceptionally clean with very good audio. Considering this, the K3 plus XV144 while probably the best combination I have ever come across on receive is not ready for use on transmit just yet because of the ALC issue if you use a sensitive amplifier. One other minor point, with large chunky VHF coaxial relays, the 20mS TX delay is not quite long enough, but still much better than those rigs with no TX delay at all! You probably still need a sequencer. Mike Giulio Pico wrote: > > Before you ask... > Firmware Revisions: MCU 2.34; DSP 1.89. > > 73 de Giulio IW3HVB. > > ___ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > > -- View this message in context: http://n2.nabble.com/K3-and-XV144-strange-behaviour-tp1079275p1079315.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 and XV144 strange behaviour
Considering this, the K3 plus XV144 while probably the best combination I have ever come across on receive is not ready for use on transmit just yet because of the ALC issue if you use a sensitive amplifier. Next time you set this up and *after* you have the drive set, set CONFIG:TX ALC to OFF. Then see if you have the same problem. If you are running SSB, you might also try setting CMP to 0. 73, Lyle KK7P ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com