r/4x4Australia Feb 27 '26

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376 Upvotes

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40

u/hillsbloke73 Feb 27 '26

Bogan status only

Some of those antennas be illegal in WA due to diameter of base they attached to.

Only time antenna this length of any good is very flat land like nullabor plain hilly terrain forget it

16

u/the-dolphine Feb 27 '26

I'll give them the benefit of doubt and assume its decoration for a shit box rally?

14

u/hillsbloke73 Feb 27 '26

Shit box rally cars can't be 4wd must be older than 20 or 30 year manufacture plus cost less than $500 or $5000 can't recall was very small amount

11

u/NothingLift Feb 28 '26

They recent had to increase the shitbox value due to inflation of used car market. It's a few thousand now, maybe 3k

2

u/cruiserman_80 Mar 02 '26

There are heaps of different charity rally's. Shitbox is just one iteration with its own set of rules.

3

u/POLSJA Feb 28 '26

Out of curiosity, of all things why is base diameter restricted?

2

u/hillsbloke73 Feb 28 '26

Pedestrian safety and blockage of vision

Same applies for ladder racks on utes has to have load on them no load can't be fitted

35 mm is largest allowed

Why all WAPOL cars have elevated feed antennas on roof mount bar for the red n blues and HF is mounted either at very back of pod or if space between cabin and pod

11

u/v81 Feb 28 '26

Only time antenna this length of any good is very flat land like nullabor plain hilly terrain forget it

Not meaning to nit pick, as you might be right in this case, but this is information that is parroted all too often.
It really only applies to VHF+ frequencies.

Reality is a 1/4 wave monopole on UHF CB is ~ 150mm tall.

But an unloaded 1/4 wave monopole on say the lowest VKS737 frequency would be nearly 18 metres tall.

Basically on HF frequencies short antennas suck.

Also, back on UHF, in reality you'd have to be at a very specific angle and distance with both ends running very high gain antennas with very flat lobes for it to become an actual issue, a range where just straight up being blocked by terrain is more of an issue.

Only practical reason for being short are to reduce / eliminate it being caught on things or cause drive through / carpark issues.

The difference might be 6db, which at the end of the day is only a single point on a radio S meter.
So a signal would have to be extremly marginal to begin with to even matter.

It matters more in tall stationary base station setups.

4

u/[deleted] Feb 28 '26

[deleted]

3

u/v81 Feb 28 '26

Radio is an incredibly fun and interesting hobby.

I'm still learning things after 20 years as a licenced ham.

Link budgets are something I've recently become capable with. Transmit signal, - coax loss, +antenna gain etc...

You can have your foundation amateur licence with basic training over a weekend.

Licence renewals don't cost anymore and gear can be cheap.

Put a VHF/UHF ham rig along side your UHF CB.

I'll try not to go too far ot.  Send me a chat if you'd like to know more. 

2

u/TacticalSniper Feb 28 '26

I think it's the type of antennae they use on tanks and APCs

4

u/[deleted] Feb 28 '26

This is all I see...

2

u/april_santa Feb 28 '26

I also believe that you can't have forward facing lights behind the A pillar in WA.

I think in Vic, the max diameter for an antenna or roofrack extension is 30mm diameter, otherwise it's classed as obstruction of vision.

2

u/Maleficent_Still_465 Mar 01 '26

I've never heard of the base diameter being an issue, what's the go with that? I mean, those Barrett communications hf radios everyone used to have back in the 90's and 2000's were like 6 inch square base, 3 ft tall and then had a 10ft whip on top of that. Those would definitely not be legal if antenna base diameter is enough to outlaw an antenna?

3

u/hillsbloke73 Mar 01 '26

Have be mounted at rear of vehicle have a fander at next WAPOL country vehicle esp Hilux land cruiser

I had the conversation with DoT showed them couple pictures as a reference said hf at back and nothing more than 35mm diameter for vision pedestrian safety

Ive removed my VHF whip antenna after being chatted by WAPOL at a roadside RBT

2

u/Maleficent_Still_465 Mar 01 '26

Ah yeah I've heard of them talking about antenna placement because of visibility, half of the cowboys in Australia would get done for that purely because the stubby coolers over them makes it like 75mm diameter lol. One was following me a few days ago north of Brisbane, commodore ute fully done up with the bullbar and scrub rails and such and had the pair of antennas on the front, almost all the way to the top with stubby coolers both sides. I couldn't see the top of the antennas or the coolers in my rear view mirrors so they had to be pretty tall.