Bias Circuits for RF Devices by Iulian Rosu, YO3DAC / VA3IUL
I came across this PDF while trawling the net looking up information about something or another and found it to be a really great resource on biasing all sorts of devices covering just about every device the modern ham might actually use in a project. My thanks goes to the author Iulian Rosu and i hope others might find this document as useful as i have in understanding a rather complex subject.
On the weekend of the 27-29th of November, Australia had its first mass activation weekend for the WWFF/VKFF programs. Over the course of the weekend, some 80 something national parks were activated, many for the very first time. Being a WWFF/VKFF nut myself, I did my part and activated 5 parks. I was planning on activating a 6th park, but ran out of time and more importantly I was running out of battery. A 100Ah can only do so much before even it has been hit too hard and needs time on a charger.
Number of QSO
First time Activation
Lockyer National Park
Lockyer Recovery National Park
Crows Nest National Park
Hampton National Park
Geham National Park
Lockyer NP and Recovery NP
On the Friday while heading out to Crows Nest, I activated these 2 parks. Lockyer is a rather nice national park and one i wish i had more time on the day to explore. With plenty of fire trails and dirt roads to hike on as well as some awesome scenery. Sadly i had exactly 1 hour in each location as we were on a tight schedule to get to Crows Nest to set up camp for the night. Qualified both parks for VKFF which is nice. Contacts made on 40 and 15m.
Crows Nest NP
Crows Nest was the base camp for all my weekend activities, we camped here Friday and Saturday nights having the whole camp ground pretty much to ourselves all weekend with the only other campers arriving about 4pm on Sat afternoon. The park itself is actually worth the visit, there are a number of walks that can be undertaking to some rather impressive water falls and to a lookout. The camp ground is basic, with well defined sites each with its own small fire pit and BBQ, toilets are long drops and there are cold showers as well.
This was going to be my night time radio operating location, but the weather gods had different ideas. With storm cells all around us both nights, 40m was a right off with 40db over storm static. Thankfully 15m came to the rescue here with a number of dx contacts being made, to bump up the numbers in my log and qualify the park for both WWFF and VKFF. Contacts were made in Denmark, Germany, Guam, New Zealand, Japan, Sri Lanka, Belgium as well as most states of VK, 1,2,3,4,5,6,7,8. All in all i was pleased with how things went from this park under some very trying conditions.
Friday afternoon, Crows Nest NP Base Camp, radioing even before we have camp fully setup HIH.
This picture is representative of the open woodland scrub that is typical around the Crows Nest region.
This is a tiny little park in the middle of Hampton township, it is not much to look at. Setup the radio gear near a pile of Lantana and looked at the road near by. I spent about an hour here, making 26 qso’s and a few park to park contacts. Contacts made on 40 and 15m.
Like Hampton, Geham is a tiny little park near Geham township, It was much more pleasant on the eyes, Being mostly native remnant vegetation and tall timbers. I spent about 90mins here active on the radio, making 31 qso and a few park to parks. Contacts made on 40 and 15m.
Noise: I took this short video just to show how bad the storm static was on 40m both nights, 15m was somewhat better, but still loud crashes rather than the constant noise that 40m was.