GB5TI EU108 Treshnish Isles

Just announced and I'm going to be part of it (yeehah!). I hope I can do it justice, I'll knacker myself trying no doubt. Gordon MM0GPZ is picking me up at the house in Hamilton at an unearthly time on Thursday 28th, we need to catch the first ferry from Oban to Mull and then make our way to the boat thats been charted by MM0BQI to Lunga. If all goes well we should be on the air late afternoon, probably 20 and 15m (CW and SSB). There are only 4 of us for a 4 day operation so please be patient with us as sleep deprivation creeps in.

Elecraft XV144 offset fault solution

Well hats off to Elecraft, they've come up with a fix for the "offset fault" I reported. Seemingly they had a crystal supply problem in the last year or so and ended up swapping their supplier. Unfortunately the new supplier is providing Crystals marked 116.010MHz. These crystals are obviously 10KHz out from the original 116.000MHz ones.

The Elecraft K3 and K2 transceivers will only correct +/- 10KHz offset in firmware so any inaccuracy in the +ve side of the new 116.010MHz crystals renders the transceiver "off frequency". Unfortunately this was the case with my supplied crystal.

The Elecraft fix involves cutting a link and adding an adjustable inductor coil to "pull" the 116.010MHz crystal within the offset capability of the K3/K2 transceivers.

I decided that after paying the extra money for the crystal oven option, I would rather have a more accurate crystal inside the oven rather than "pull" the crystals frequency using a coil outside the oven. I have now replaced the crystal with one from a local supplier:

QuartsSLab (+442071006357)
Description:
HC49u, 5th Overtone - 116MHz, series o03s
Price £21.83

This replacement crystal now brings the XV144 up bang on frequency. Now to get on with using it :-).

Elecraft XV144 and Yaesu FT-1000MP MARK-V

Whilst waiting for Elecraft to come up with a solution to the "offset fault", I decided to hook up the XV144 to the MK-V. My set-up is as follows:

Mk-V Menu settings:
3-3 (tr-disp) = 144
4-0 (rf out) = 10
8-4 (FrontEnd) = flat

Mk-V switch settings:
IPO (on)
rx ant (on)

Connections
Mk-V <-> XV144
ant B -> tx in (via 16dB attenuator)
rx ant in <- rx out tx gnd -> key in

I bought a microwave modules 16dB attenuator from Ebay which reduces the menu restricted 10W drive from the Mk-V down to the 250mW required by the XV144 (also capable of 1mW and 5W drive levels by link selection). The result is perfect, with the XV144 responding similarly to the K3/K2 1mW drive.

What is straight away apparent is that the Mk-V drive is 100% stable from first key of the mike (unlike the K3/K2 which ramp up slowly over a 10 second period on first key of the mike, thereafter stable until pwr/band/switch-on event). The Yaesu PA behaviour is so much better than Elecraft have been able to achieve to date. I didn't know if the ramp up in power was the K3/K2 or the XV144 but I now know it's the K3/K2 PA.

On first switch on the signal strength meter went to about S7 due to the MkV rf amplifier "tuned" profile. I toyed with ATT values, but felt the "FLAT" rx profile best, as this combo gave me S0 on the meter with an accassional flicker up to S1....perfect! The rx gain loss caused by engaging the cascaded 500 or 250Hz (2nd and 3rd IF) filters on the MkV can be leveled out by using the MkV "tuned" rf amplifier profile.

There is no mention of transverter operation in the Mk-V manual and very little extra in the FTV-1000 manual, but the methodology of use is that you dial in 28.000 on VFO A then change menu 3-3 to 144. This then calibrates the frequency display to 144.000. To account for the Elecraft "offset fault" I must set VFO A to 27.978 and then set menu 3-3 to 144. This brings up 144.000 on the frequency display and compensates for the Elecraft "offset fault" ...thank you thank you Yaesu! Maybe Elecraft could learn something here.

There seems very little info on the web about this subject so hopefully someone out there finds this useful.

GM0ELP AFS CW 2011

KEY CLICKS, KEY CLICKS, KEY CLICKS

Who could believe that the UK could produce such poor signals in this day and age? I'm tempted to name and shame on this blog (as the clickers had much higher scores than me), but that may be construed as hard cheese. In some cases I had to hunt more than 1KHz to find the clicker. Hopefully someone will have recorded the whole contest and has measured the clickers bandwidths. Feel free to reply with the results :-).

Is it lack of knowledge?
Is it lack of money?
Is it that no-one can get close enough to you to cause rx problems?
Is it deliberate.....?

Elecraft XV144 Transverter (my review)

Had a quick chat with a local ham (Elvin BBA) on 144MHz using the transverter yesterday and all is well apart from being 2.8KHz low on the frequency display on the K3. Actually there is a menu in the K3 to adjust offset in the firmware, but I'm already fully utilising +9.9KHz offset (max) so I'm actually 12.7KHz off. I thought it was something I had done, but apparently Elecraft's supplied crystal part has questionable accuracy. I got an e-mail from another XV144 user saying he had exactly the same problem until he replaced the Elecraft crystal with one from a local supplier and it came up bang on frequency.

So far the XV144 seems to have a very lively RX. Using my 5 ele yagi in the loft (K3 on SSB, 2.7KHz width) I get a constant S6 of noise on the K3 with no pre-amp. In comparison the IC-275E shows S0 on the same antenna. Switching in the dummy load brings this down to S3 on the K3. I used the Elecraft XG-2 mini module to calibrate the K3 S meter on 10m so the discrepancy must be the with the IF input. Listening to GB3ANG beacon it seems louder on the K3 than the IC275E. On both radios I'm getting QRM that sounds like frying bacon (blooming Christmas lights and toy chargers!) so I would expect some signal strength to be registering. I'll need to take the K3/XV144 somewhere quiet and see what it's like, I might even be able to dispense my ext pre-amp.
I have the crystal oven option and on initial switch on from cold the RX drifts about 1.5KHz in under 10 secs then stabilises. I left the radio sitting listening to GB3ANG for about an hour after initial switch on and when I came back in it was still bang on, so pretty happy with regards stability.

The TX side is typical Elecraft. On first tx after power on or band change it takes 5 secs worth of tx audio before the output power starts ramping up to the set level, 3 secs more tx after that it achieves the set output power level and stays stable.
The manual wants the output set up to be max 20W CW key down into a dummy load (even although the front meter goes up to 30W). When set up like this, on SSB the front meter on the XV144 just peaks to 15W (up to 10W LED on solid, 15W LED flickering) on tx audio. This all seems pretty normal when considering PEP to average power readings. Once calibrated using my external watt meter, the output power LEDs on the XV144 accurately track my average power reading. TX audio is reported as a good representation of my real voice.

We'll have to wait to see what Elecraft can do with the offset problem.

Elecraft XV144 day 2

Progress continues on the XV144. Now through the boring mass resistor/capacitor fitting and on to the bigger parts. Board is now looking a lot busier. The low quality plastic trimmer supplied with the kit has no possible chance of fitting the hexagonal inductor trimmer pot. I had to 'sharpen' mine to allow an easy fit. I'm taking my time, doing things right and so far haven't made any mistakes. Christmas has been and gone now (thank goodness) so now only have a birthday, a curling match, a new year party and visiting relatives to slow progress :-).

Elecraft XV144

Merry Christmas All,

Working on my XV144 right now. No surface mount stuff to fit, so all similar to any other kit.
Some things to note:

1) Some of the component pads are smaller than normal, so a really fine tip solder iron tip is necessary (0.3MM or smaller), also really fine solder 60/40 0.5mm is a must to avoid shorts/splashes.

2) There are large copper fill areas on the PCB which act like a heat sink which wicks the heat away from the pads. This means solder tends to prefer to stick to the tip of the iron rather than to the pad. The fine iron tip exacerbates this situation. The solution is a proper variable temperature solder station and maybe a fine iron tip (chisel profile?).

3) Not all component leads when bent close to the component body will fit the PCB. The component has to be offered up and leads bent to fit PCB. Takes a bit longer, not as good/easy as the K2.

4) Some of the larger wattage resistors have to be mounted above the PCB to allow air flow all round the component.

5) Elecraft manual is brilliant as usual

Progress so far-