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Hi folks! I'm a bit of a hardcore lurker here, and while I read much, I post little. I'd first like to commend everyone for maintaining such a fantastic community and resource for soundies everywhere! I've learnt (and continue to learn) so much from here. One thing that someone said (can't remember who) but it really stuck with me, was that in this day and age a good production mixer needs to be as knowledgable as possible about RF, and so I've been researching as much as possible and trying to come up with ways to improve my professional practice. One day soon I'll own a full Zaxcom rig to go with my Nomad, but for the time being I'm trying to hone my skills, and get the most out of what I have (G3s). I think one of the most important purchases to further this ethos was an RF explorer, which immediately gave me invaluable real-time feedback on what was happening in the spectrum nearby. I also use the FreqFinder app to help coordinate frequencies and avoid intermodulation issues, and finally have been modding my G3s with SMA connectors to use external antennas / distribution (details are in the topic about this also in the DIY group). I also purchased a bunch of Nitinol super-elastic wire and SMA male crimp connectors and have been making my own whips. So finally to the dipole adapter! I was thinking for a long time about a versatile and easily made dipole antenna (plenty of people make them quickly and easily from coax), but I wanted it to be relatively sturdy as well as compact, and I also wanted to try and have some sort of integrated Balun. I finally discovered the sleeve dipole (which uses a 1/4 wavelength sleeve around the feeder coax as both the lower half of the dipole and also acts as an integrated balun of sorts). So with a few plumbing fittings, some copper pipe and end caps and couple of SMA connecters the 4D mk1 was born! (Dave's DIY Dipole 'dapter). Key points: # - I wanted something that could be mounted almost anywhere easily so there is a 1/4" 20 mounting point epoxy'd into the bottom which fits a squillion different common mounting thingies (pic below shows it attached to a little ball head and 1/3" thread adapter on to a mic stand). # - I made it so that it is an adapter not a complete dipole - you simply screw a whip on the top and suddenly you have a dipole! I've yet to discover the effect of 'tuning' a dipole with only one half of it changing length though... However the parts are so cheap that having several for different 'blocks' would be no trouble - and maybe the thickness of the sleeve half of the dipole would increase the bandwidth a bit? # - It is also pretty easy to attach to a harness (as shown) and the top whip sits above the shoulder for a good LOS to the TXs if they are behind. Finally, I also have heaps of questions and ideas about RF and antennas that I'd like to discuss and share so perhaps this topic could also be a place where people can talk about the sort of things that aren't normally found in HAM radio texts? Cheers!
We've added a series capacitor to the SNA600 to make it the "a" version. The previous version was a DC short to ground. This new capacitor makes it easier to use with the Venue receiver or others that provide a DC bias on the antenna port for powering remote, amplified antennas. Actually, the capacitor can be added with a little care to previous SNA600's. Any surface mount ceramic capacitor from 100 pF to 1000 pF can be used. If you need the cap, send name and address to email@example.com for a freebie. If we had had our Lectro heads screwed on tight, we'd have put the cap on the original design. Best Regards, Larry Fisher Lectrosonics p.s. It does not affect the antenna RF performance, good or bad.