Saturday, October 22, 2011

Finally 24GHz QSO !

My first 24GHz 2-way QSO with John WB9PNU happened on Saturday 10/22/2011 at 9:36am local in EM48tm:

AF4JF


WB9PNU

I have written some more info on SLAMS web site. You can also find some more pictures from the event there.

Tuesday, October 18, 2011

First 24GHz Success !!

We have tested my new "24GHz-xverter-to-be" in WB9PNU's lab. John's spectrum analyzer definitely shows a need of a waveguide filter, but otherwise didn't reveal anything bad. Output power on 24GHz seems to be comparable with John's xverter (John uses harmonic mixer x4 from 6GHz and 144MHz IF, I am using different mixer x2 from 11.88GHz and 432MHz IF).

Important is, that we have heard each other today! I have to make a little change on my receiving preamp, but we are generally ready for first field test on Saturday 10/22 during SPRINT Microwave contest.

Both stations on the test bench
(IF radios are FT-817 on both sides):

My station detail:


Let's hope for first QSO this coming Saturday!

Saturday, October 1, 2011

Not too many news ...

Well, I am quite busy with my job duties. I only managed a few ham-radio related accomplishments since my last posting here. I also bought fantastic paddle on eBay .. it's a HiMound Iambic Keyer:


Yes, it came with the base .. looks funny, but feels good! I bought this paddle for outdoor use on hilltops during our microwave events and intended to fasten it directly to the tripod, but probably will keep the base attached to the paddle now.

I am almost done with my first 24GHz transverter - just a harmonic mixer using ELCOM synthesizer (posted here earlier). Following pictures document it:





This one shows how simple it is - 12GHz coming in from the left, through the SMD capacitor, to the BAT15 antiparallel diodes and out the box on the 24GHz side. Well, there also is the IF signal of 432MHz coming in through the trace from the bottom. This works both ways, transmit and receive. PCB artwork was designed by DB6NT. Parts were magnified a little, real size is approx. 1/10" for the diodes and little smaller for the SMD capacitor. Smaller board is the new PIC controller for the synthesizer.


This is top wiew of the transverter box .. the 12/24GHz trace is on the bottom side at the right, below the empty space in the enclosure above.



All pieces are assembled, time to put everything together. That will take me a day or two, so I anticipate my very first 24GHz QSO to be made very soon, probably next week!