Sorry it has been so long dear readers. Currently, I am putting up about 166 feet of cedar fence at my house and time has not been abundant.

This week, I went over to my friend Les’ (K5RXQ) house to analyze his new antenna. It was a slightly modified Carolina Windom that was supposed to be resonant on 80 meters. I took my trusty MFJ-269 Antenna Analyzer with me. Les has a fantastic MFJ roller inductor tuner, but I wanted to see where exactly he needed for it to be used, and I imagined he did too. Funny thing…after we got done analyzing the antenna, the performance was flat on all bands but 80 meters, 160 meters, and 10 meters. I got a chuckle out of that, but the tuner picked up the slack nicely. I did manage a contact to Italy on my first try.

When i went to grab my tuner, I powered it up. 7 volts. Not enough. Apparently it sat so long that the rechargeable batteries were not charged up enough, and there was no 12 volt wall wart in site. I eventually found an unregulated one, and quickly learned that the circuit powering the analyzer is unregulated as well. Upon turning it on, the meter showed 19 volts. WOAH! (For reference, this was a wall wart for an old 3Com network hub) Good enough for government work, anyway. There HAD to be a better way.

Les and I thought it would be a fantastic idea to have the analyzer feed off of 12 volt input from wherever an Anderson Power Pole equipped station was, since we do work with R.A.C.E.S, and there is usually no reliable 110 volt service where we are deployed. For those of you who didn’t guess at first, the Anderson Power Pole is our standard connector for R.A.C.E.S. equipment.  At first blush, after I started tinkering with it, I took the analyzer completely apart, which was no easy task. The idea was to come off the DC input lugs with a 14AWG pigtail and drill a hole through he chassis where Anderson Powerpoles would be attached. After about an hour and a half, the idea was scrapped. There is simply NO ROOM under the hood of that thing to facilitate the mod.

Instead, I came up with this:

(Click image for full size)

The above jumper allows me to convert the 12 volt DC modular jack to Anderson Powerpole 12 volt input!

Here is a picture of what it looks like in action (Note: Generally speaking, this is a proof of concept. The actual working model would either be longer, or, have an attachment for a jumper to the distribution block):

(Click image for full size)

Now I can use my analyzer in the field without worrying about depleting the on board rechargeable batteries. What’dya think, MFJ?

Of course, I could use this adapter for lots of things, but honestly, I don’t own much that I would do a R.A.C.E.S deployment with that doesn’t have Powerpoles already.

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