After 3Y0Z: 20M Yagi Becomes a 2 Element 30M Yagi (?)

By just adding coils in each of these elements and extending the boom to 12′, I can have an awesome 30M yagi. I have always really liked 30M – because it offers a “respite” from contests – which I m not at all interested in (unless I can get some 160M counters).

But during the deepest part of winter, 30M does act a little like 20M, but from my experience, 30M is usually at best more like 40M. I am a dyed in the wool CW guy who “tolerates” other modes – so 30M offers a CW bigot a great place to play.

One commercial antenna is the JK – 302:

I already know from having the N6BT DXU-32 that even a coil loaded “shorty” yagi on 40 or 30 would be at least 1 dB better than a 2 element vertical array – so its something to ponder.

Stay tuned – I’ve seen how excellent 30M can be today, so . . . .



LZ307MU on 30M at 3:30 PST (2233z)

I was very surprised to hear Bulgaria on 30M at 2200z, and then after a while I decided, what the heck – why not call him. Sure enough – he had a real hard time hearing me, but I used the DX Engineering DV-40-P – my 40M vertical array on 30M – because its SWR is just fine.

I proved today that this antenna is great on 30M. So now I have very good antennas from 160 – 20M, and after getting the 20M yagi up another 20 feet or so, I should be in great shape to work 3Y0Z.

Image from SolarHam

Conditions were quiet, that’s the main reason why I worked him, and so today was a pretty special day – with ZS5IE workable until he QRT’ed at 9:30 AM PST, and LZ workable in the 3 PM PST hour – both were classic “special” winter time conditions.


Preparing for 3Y0Z

My homebrewed 2 element 20M yagi is not up high enough, and as a result of last weekends antenna work, I now have a spare Spiderbeam 40′ pushup mast. I can put this on my back deck and then get the yagi up ~50′ since the deck is 8′ off the ground. Its only 27′ up now. 

I also took down that center element of the Mod Bob, so now I can move the yagi to a better place.

Modeling seems to indicate that raising it that much higher will make a significant improvement in take off angle and add a little bit of gain too.

This my backup station – and while I also have the Elecraft KXPA-100 100 watt amplifier, I have found that my Expert SPE 1.3K only needs about 10w drive to get 1 KW out. I will order a cable that lets the KX3 drive the SPE amplifier. I also have the KPA-500 and KAT-500 in a closet, so I have all the backup I need. The 40M and 160/80M antennas are set, and on 30M, I can use one vertical in the 40M array.




ZS5IE Worked S9 at 9:30 AM PST (1630z) on 40M

It was quite amazing today to hear ZS5IE this late in the morning on the fabulous 40M Long Path. I actually worked him at 1630z where he was S9 and I was S5. I can’t remember this path being open this late. Iain was running 300 watts to a 2 element inverted vee and I was running 1KW to my DX Engineering DV-40-P phased verticals.

Guess I’m good to go on 40M – hi hi

Two Great Lowband Antennas

If you have a good radial field, it’s hard to beat an Inverted L on a small lot. It’s easy to match it on 160M and 80.

If you don’t have radials, the Mod Bob is a great way to get on all low bands on a small lot

The Mod Bob requires a good balanced tuner like the Palstar BT1500A

The u.rat: switching vs stepping

The one thing I really don’t like about the u.RAT is how slow it is to turn the roller inductor. I also noticed that you start wearing down the wire on the roller.

One answer would be to use a relay board. You could switch in taps of a fixed inductor, and use the switches on the KPOD to control which tap you want. 

In fact, you could do the same thing with doorknob caps, but the variable capacitor that I have tunes nicely with a stepper motor, and with no wear or tear on the component as there is with the roller inductor.

Dios de los Muertos

Yesterday we had the best Halloween party at Credit Karma. I felt like a kid again – kudos to our wonderful Events Team – they knocked the ball out of the park!. What an amazing company to work for – I’ve been at CK for 8 months and just love it.

The Inverted L with home brewed remote tuner at the base has a wonderful distribution SWR curve. Its PERFECT for my needs

I found that I can tune the antenna at the base and shift the SWR curve so that my SPE Expert 1.3K FA amplifier then finishes the tuning just perfectly in the CW portion (and even the lower portion SSB) of 160M (and the SSB portion of 75M, and that’s perfect since 99% of my work is in the CW portion of the 160M band, and then I check into that nightly 75M SSB net as well – just for fun.

Because I rarely use 80M CW – and if I did it would be 10 minutes to go out and manually tune – the need for the u.RAT goes away. The u.RAT most definitely  would have been needed on the Mod Bob to tune 4 bands and across each of 160, 80, 40 and 30M.

Speaking of the Mod Bob – if you want all 4 of these low bands and can accept that the antenna will work DX and domestic stations – albeit a little bit of a compromise – then the Mod Bob is a GREAT antenna – the only one that I have come up with that can do this (without requiring a good radial field). A good balanced tuner like the FABULOUS Palstar BT1500A is required. I have a funny feeling it would beat the old and very low loss Johnson Matchbox on 160M because if I remember right – they only cover 80 – 10M, but Ed, AC6CX says you can add some doorknob caps to compensate for that. I sure love those old Matchbox tuners – some gear is just classic and was so well done.

I’m very glad that the SWR curve above is what it is because it shows that my radial field is not terribly lossy. The kiss of death for using radials is if you end up with a broad banded antenna – especially on 160, and as you can see, this isn’t the case on any of the bands. 60M is covered too – but I have no interest in what is like a CB channelized band. If the FCC ever did that to any of the other bands, that would ruin ham radio for me.

Wow – FT5WQ/MM is very loud on 40M right now – and I worked him easily. I wonder where he is? I already have Kerguelin and Crozet, so I am covered.