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23cm activation 05/DEC/2019 W6/CC-045

Looks like we may have a break in the weather on Thursday, 5 Dec that will allow for a 23cm activation of Mount Diablo.
I just received my SG-Lab transverter and will be using my KX3 as the IF and a 10 element yagi. With this new equipment I should be able to operate SSB, CW, and FM with about 3 watts out.
My goal is to work into Bakersfield, and Redding; but the Sierras, and Santa Cruz mountains are also possible.
I will be using 146.52 to coordinate contacts. If you are interested in 23cm contacts please message me so I can plan directional coordinates for the yagi.
ETA of 1900z is approximate due to traffic conditions between Sonoma County and Mount Diablo.

I recommend setting up in advance the transverter, power levels, cables etc using the setup you will have on summit. There is a power sensitivity adjustment in the transverter you need to preset so that the power from your 144 mhz rig does not overload or under-drive the transverter. I use 0.5w from the ft817 to drive the transverter.
I use BNC cables between the various parts of the setup, so I leave SMA-BNC adaptors on the transverter.
Check also that the transverter is configured for single shared antenna on 1296, there is an option for it to use a separate antenna connector for the receiver. If that is incorrectly set, the rx gives rather disappointing results.
73 Andrew VK1DA/VK2UH

Thanks Andrew. I agree with your comments regarding setting up at home before arriving at the summit-a lesson learned with other gear on other summits! For this trip I will be using SMA/BNC adaptors; but I have ordered SMA Male-to-Male cables to simplify connections for the next activations - the KX3 2M antenna connector is SMA.
At present there is very little SOTA activation using 23cm in California, but we are working on it. My original posting is part of the campaign to encourage 23cm activity by advertising my 23cm activation. My chosen summit is well placed to cover a wide expanse of the central valley as well as into the Sierra Nevada mountains and the Costal ranges.

Hi Joe,
Sounds good. Re increasing the activity on 23cm, reaching out to the non-SOTA users of that band can be time well spent. Most 23cm operators are keen to make more contacts and are pleased to hear of more activity on the band as it is in general a band for specialists, whether they are EME folk or vhf weak signal ops.

We have found in the vk1 area that notifying the non-SOTA ops of activities is really worth while. Rather than struggling to qualify on 23cm, it can turn into a morning where many contacts were made. Having more than one sota portable out on an interesting hill can have a multiplying effect. And incidentally it demonstrates to the home station operators that SOTA isn’t just low power HF. Hope it all goes really well for you.

It should be feasible to find the vhf dxing mailing groups to post some “alerts” there. Sometimes you just need to link to the right person and they provide the publicity as they have the contacts.

One of the well known names for 23cm is of course Jim W6PQL who has helped many 23cm ops make their stations perform better, through his amplifier designs and kits.

73 Andrew VK1DA/VK2UH

A successful activation today. First, and most important, my new SG-Lab transverter works very well - used it for SSB and FM. Used my KX3 as the IF for the transverter. My KX3 showed 1296.100.20 and the chasers showed me at 1296.100.00.

Worked three 23cm stations - worked all three using FM and 2 with SSB (the third station did not have SSB). On SSB one station copied me 5/5 and the other copied me 5/9+30.

My 10 element yagi failed - the center conductor in the SMA connector broke - another lesson and a minor repair, but not a summit repair.

My 3 element PC board yagi worked perfectly - a WA5VJB product - easy to pack and carry!!


What was your best DX? That central valley should alow some long contacts!


My plan was Bakersfield and Redding both 300+ Km; but today local, 20, 50, and 73 Km.

When My 10 element yagi failed I used the 3 element WA5VJB.

My best DX so far is 130 KM

I agree with you that Mount Diablo has a great look at the central valley - so I will go back - probably right after the first of the year. I think I should be able to work Frazier Mountain w6/cc-003 and Table Mountain w6/ct-067 for S2S DX they are probably 350 KM.

Glad you got some contacts. I totally forgot to take my FT-911 to work and watch the spots. Next time!


For DX, there is a NorCal 23cm linked repeater network that extends to Tahoe. Probably worth giving a shout on that and begging for contacts.


I just checked and Frazier is 434 km and Table is 543 km. I don’t know if that is even possible but Table is 7516’ and Frazier is 8013’ - Frazier is close to the I-5 at the Grapevine - but winter has finally arrived and these adventures will need to wait for next summer.

I did go to the Fremont repeater and ask for contacts, but no joy.

I’m going to try to figure out how to check in to the Bozo Net from home - If I figure that ou I should be able to get some skeds.

Wow…i can only dream of 400 km contacts here in AZ…LOS paths max out at abt 200 miles here…and i only run 1 watt on 23 cm…