a****f stacked Dipoles

[Banus_radio]

I was looking at A****f Pictures and noticed they put ferrite beads on their dipoles as seen in the attached pictures. Can anyone explain what purpose this serves?

Also I noticed a join on each dipole, looks like so239 thru piece and two plugs covered by heatshrink, is this where he has joined the 75ohm to the 50ohm to make a harness? Also they have a splitter box! On my bench when i run power through a 'through piece joiner' it gets red hot. Can you imagine the amount of power being lost in the plugs for the splitter box and then the plugs for the joins. There muct be a much better way to do this??

Its the ferrite bead that has got me wondering

aareef.jpg

aareef ferite bead.jpg

[Analyser]

The ferrite bead is most likely to try and stop the coax radiating.

Proper joiners are the way to go when connecting cables together but (as you've found out) the PL259 types tend to be really low quality so either heat up/ fall apart/ melt with anything over 200w or so.
My choice when doing this type of thing is to use N-type.

I'm not sure what's inside the "splitter box" but it's probably a bit of wire or some coax and therefore fairly shite. A simple T shape joiner would be better.

[Albert H]

The coax wouldn't radiate if the plonker had actually used a balun to feed each dipole (like Stephen and I did). Many people don't realise that a dipole is a balanced aerial. The feedline is (usually) unbalanced coax, so a modal transformation is necessary if you're going to get anything approaching a good match and effective radiation.

This is just one of the reasons that I like end-fed aerials - they will directly accept the unbalanced coax feed. It's also less obvious - a vertical aerial could be anything - even for CB - so the idiot rig thieves don't realise what they're looking at!

[powerfull]

even the london crew build better than that crap with their 2 bits of string 75 ohm harnesses pmsl and that's saying something, this guy is trying to remix the double stack with some gimmicks to make it look worth buying, i wonder how many idiots have bought one to get out no where lol

[yellowbeard]

even the london crew build better than that crap with their 2 bits of string 75 ohm harnesses pmsl and that's saying something, this guy is trying to remix the double stack with some gimmicks to make it look worth buying, i wonder how many idiots have bought one to get out no where lol

You have to keep that bit of string wet or the SWR starts to climb on it.
This a****f guy can't be that dumb - he seems to be able to get lawyers cheaper than silvered mica capacitors if the stories about him are true.

[Albert H]

That was true some years ago - he tried to sue Stephen Moss for "passing off" Stephen's own designs as "Veronica" products. Stephen had stopped using the "Veronica" name several years before, when Hollings set up his "business" using the name. Stephen successfully demonstrated in court that the NRG products were developments of the circuits that he'd developed years before (he produced the original design notes from the 70s and 80s) and that they bore little similarity to the hack work that Hollings was turning out for "Veronica" and that Hollings had stolen incomplete, old designs that he was incapable of completing.

One funny example - Hollings copied Stephen's really cheap stereo coder. Because of a significant omission in the design, the input sockets couldn't be labelled "left" and "right" because they'd come up at random just like one of those "heads or tails" circuits so beloved of the electronics comics. Adding just a capacitor, diode and resistor would guarantee the channel polarity, but Hollings couldn't work that out!

Stephen's cheap coder had "left" and "right" inputs and a proper mono switching circuit that disabled the stereo pilot and turned on the channel switches to allow both channels through. It also had LED indication of mode, and only needed a single switch contact to achieve the "click-free" switching.

Hollings had copied Stephen's two-transistor oscillator, but didn't understand it, so "his" version was unbalanced by component choice and loading, so it produced a whole stream of harmonic products rather than the pleasantly clean signal of Stephen's original circuit.

[MiXiN]

I just did a quick search on this guy, and as well as being a nob, he sounds like a proper soft Mother's boy. He's pretty much disliked all over - https://groups.google.com/forum/m/#!top ... HpgWPSoLFg

[Albert H]

Stephen, Christine and I had endless fun at Hollings' expense - the guy was (and is) a complete loser. His "business" is a joke. Several of us used to take it in turns to phone up his "business" and ask him endless technical questions that he couldn't answer.

He upset some people in Halifax, and they took to dialling his office number from phoneboxes, and leaving the phone off the hook, tying up his only phoneline for hours at a time!

[thewisepranker]

even the london crew build better than that crap with their 2 bits of string 75 ohm harnesses pmsl and that's saying something, this guy is trying to remix the double stack with some gimmicks to make it look worth buying, i wonder how many idiots have bought one to get out no where lol

Spot on.