Wyoming on 902 MHz EME

 April 19, 2024

As promised, I rolled down to Yellowstone Park this afternoon. I was surprised to find the dirt road into the Big Horn Trailhead was still under four feet of snow, but the wide pullout off Route 191 was still 25 yards into Wyoming so that was where I set up. I did have two different sets of "Lookie-Lous" stop and ask about what I was up to. The looks I got were priceless - they thought I was loonie!

Anyhow, I worked all callers again. I did have to grapple with wind moving the dish off axis, the fiberglass center post just was too slick to hold in the light breeze. A few cinch straps fixed the problem, and I already have a long term cure thought out. Once on the moon the SL-1 tracker kept me there.

Worked (at apogee no less) were AC0RA (-24), W2HRO (-20), W5AFY (-23), VE4MA (-23), W7JW (-23), K0DAS (-23), N0LNO (-23), KC0SKM (-24), W6TCP (-25), K0DSP (-24). I appreciate the activity, it makes these outings well worth the effort. LoTW upload done.

Bonus: I saw elk, a moose, and a small herd of big horn sheep on my travels to and fro.

 

DN44lw32ns Wyoming (just). Big Horn Trailhead was still snow bound.

Yellowstone Park, WY (DN44lw) with the moon riding high. Click on the photo to get a hi-res version.

Back seat station, no quick stops!

Easy 902 MHz EME

April 13, 2024

    Of course it's easy if you spend a week re-doing every cable in the station with heavy duty connectors, and pondering where is the quietest location within driving distance. A friends cabin in Tom Miner Basin (DN45me), just north of Yellowstone Park, is the ne-plus-ultra for a quiet spot. So that where I went today. It was an exceptional spring day - usually the road up to the cabin doesn't go snow free until mid-May. This year it was an easy drive in my Subaru Forester. We're talking 71 degrees at 6,500 feet elevation!

Of 11 stations calling I worked 10! W2HRO (-21), W7JW (-21), W5AFY (-20), VE4MA (-21), AC0RA (-22), K0DSP (-23), K0DAS (-23), N0LNO (-23), KC0SKM (-23) and finally W6TCP (-23) after an hour's chase. 

I have ready access to this location, so if you still need Montana I'm happy to roll uphill again.

2.4M dish, 500+ watts, and no stinkin' noise! The wicker chair was a nice touch.

The Theodolite app helps when setting the dish up. Looking 81 degrees.

902 MHz EME Challenge Parts III & IV

 March 30, 2024

The new amp rocks with in excess of 500watts, so I threw the station into the truck and drove northwest to Canyon Ferry Lake for moonrise on March 25th. The 902 noise was down, the wind was down, the moon came up, and I failed ... again. I had lots of callers including W5LUA with his best of band signal, but I heard nil, and was heard by none. Hmmm, that's a hint - I'm not on frequency.

Sure enough, at N1AV's urging, I checking the local oscillator settings in the SG transverter.  I was only 24 Mhz off frequency. The change of one, stinking, shorting block was the cure. Note to self: RTFM, it's only four pages!

A pretty, too quiet, early spring evening on Canyon Ferry Lake DN46fj.

 I re-grouped and on March 27th, from my local operating spot here in Bozeman, I made four 902 Mhz EME contacts. This gave N1AV his 50th State for W.A.S. award #5 on 33cm, and I added a sixth band to my EME exploits. Others worked were W5LUA, W2HRO, and KU4XO. 

Noise is still an issue, but the road to the mountain cabin north of Yellowstone Park gets better everyday as the snow and ice melt off and the mud dries out. That has to be a great spot to get away from the RF smog. I'm looking forward to operating from that high, off-the-grid perch.

902 MHz EME Challenge Part II

March 10, 2024

After two sessions trying to get the NXP LDMOS pallet to play nice, I replaced it with a W6PQL pallet. It took some fiddling to re-jigger the 12 vdc bias circuit, re-do the 50 vdc VDD lines, and solder the RF input and output coax in place. Slipping two layers of index card stock between the circuit board and the heat-spreader works really well - otherwise the copper heat-spreader draws the heat off too fast to get a good, clean solder joint. I could even solder the conformable coax in place with a 45 watts HAKKO soldering station cranked all the way up. 

Today was the smoke test. 3 watts of drive = 400 watts. That's 21 db gain which is very nice! I have some level setting to do with the transverter's 144 MHz drive level, even at 0% power indicated, my IC-9700 hits the transverter a bit too hard. A 3db 10W attenuator is on the way. 

I've also discovered my usual operating spot in the barn just south of town is not a good location for 902 EME reception. There are just too many 902 - 905 devices chirping away across the band. For the next test I'll retreat to the mountain cabin just north of Yellowstone Park as soon as snow comes off the access road.

In the meantime I've been streamlining the station's cables and generally getting things ship-shape for some summer travels with 902 and 1296 gear.

Onward!

Finished soldering the .250" conformable output coax in place.  Note the card stock to be removed.

The 902 MHz EME Challenge Part I

 February 10, 2024

There seems to be a sudden surge of interest in achieving Worked All States on 902 MHz. W5LUA has just nailed down WAS #1 and N1AV has 48 States in hand. I was asked if I could active Montana and other western States via the moon to help the cause. Sure! 

KA6U has been out and about including 902 EME on his epic road trips, so folks have been upping their W.A.S. totals already thanks to his Herculean efforts. Here's a taste of his activity.

Many hands make a 902 moonbounce station - Ian, W6TCP sent me a NXP Semiconductor 915 Mhz test pallet to work up into a fully functioning amplifier. I managed to stick things together in two four hour work sessions to create one of my "KISS" amps, but but initial testing was a bust. After some expert help from W6PQL, we can now say, "It's alive". I should have 350 watts to play with given the drive from the transverter. The nice thing about the NXP pallet is that the bias voltage is generated directly from the 48 VDC  VDD supply.

N1AV plyed me with a loaner 144 MHz to 902 MHz transverter he had picked up along the way. W2HRO sent west a patch dish feed for my 2.4M dish. I've have two superb WD5AGO pre-amps in hand, so I'm close to first RF on my sixth EME band! Later this month after a long-planned trip south to bask in the warmth of Mexico we'll see what can be done.

I understand Jim, W6PQL is now offering 902 amp pallets. So QRO power on the 33cm band is no longer hard to generate.

So this is a group effort to get some western States on the air - have camper will travel*. 

* Once I won't freeze my butt off - we've seen -40 degrees Fahrenheit (-40 C)   here in Bozeman this winter!

NXP QRO pallet with bare-bones support circuitry. KISS!

The W2HRO feed is a big boy! The hybrid label was applied upside down.