27MHz CB Radio ...has anyone fitted......?

Noise is either coming in through the RF input, bit hard to stop that.
Or
The power supply.

If it's the power supply a low pass filter is the go.
Generally this consists of puting an inductor in series and a capacitor in parrallel with the 12V suppy.
ie the inductor goes in the positive feed and the capacitor in between the positive and negative feeds.

Mobs like Jaycar sell inline filters to make things easier.
Something like this will do the job.
http://www1.jaycar.com.au/productView.asp?...eMax=&SUBCATID=
Also make sure the set is well earthed.


Cheers
Ken

it is earth through the antenna and also back to the battery.


in the good ol days i used to regularly pick up new caledonia with a station master and a pearce simpson super tomcat.

on rare occasions when the skip was good it would reach a lot further(but very briefly)

dems were the days......

I am using a MHz set and have the same problem with noise :cry: but will try the filter from Jaycar. :idea:

I am on ch 12 when driving the RR on all the time but not much happening

Kai

i will put a call out for you when i leave work......



reckon you will pick me up on 12?

No as i am in my work car and the CB is in the RR and SYD is a bit fa i think.
but nice try :wink:
Kai

May I hijack this thread briefly with a couple of my stupid questions?

I have a UHF in my car and it has a short thin ariel about 30cm. I have borrowed in the past a mate's 2m ariel when going out bush. Much meatier looking.

1) does size always have something to do with performance in ariel world? Could the new short ariel provided with the unit be better than the old large ariel that my mate forgot how he came by? It may be an ariel from a house based unit.

2) does whacking a bigger ariel help or if the ariel is being driven by the same unit therefore same power then it makes no diff? I have no idea if the tree trunks you see on the front of utes are matched to a proportionately powered unit.

I am wondering if my placing the relatively giant ariel is worth it. I suspect it is but I'm only assuming.

Quote:

---

Originally posted by JamesH
May I hijack this thread briefly with a couple of my stupid questions?

I have a UHF in my car and it has a short thin ariel about 30cm. I have borrowed in the past a mate's 2m ariel when going out bush. Much meatier looking.

1) does size always have something to do with performance in ariel world? Could the new short ariel provided with the unit be better than the old large ariel that my mate forgot how he came by? It may be an ariel from a house based unit.

2) does whacking a bigger ariel help or if the ariel is being driven by the same unit therefore same power then it makes no diff? I have no idea if the tree trunks you see on the front of utes are matched to a proportionately powered unit.

I am wondering if my placing the relatively giant ariel is worth it. I suspect it is but I'm only assuming.

---

The only difference the length makes to a UHF aerial is it allows the signal further range aft as the signal clears the roof when its taller than the roof line (ie 1.2 mtres) and not bounces or deflects of if lower. The thin aerial will be inferior as it will loose signal strength in a convoy situation if the last car a long way back. My mate has one like yours on his Rangie and I've never had a problem hearing him crystal clear.

The ute boys in most cases have the big aerials only for pose value, I've seen them in utes with no CB at all and a dozen aerials swinging, some with twin aerials on bull bar = 1 CB, 1 for pose, it's just become an accessorie - must have if you own a ute, like extra large RM stear horns decals and B&S ball decals and lots of PUB stickers, just decoration :!: [img]style_emoticons/<#EMO_DIR#>/laugh.gif[/img]

The DB rating of the UHF aerial is what indicates the distance the aerial will recieve, a 4.5 db will throw a shorter oval in length, round sideways but better in mountainous country (& probably the best all round especialy the GME 4705 will reach to about 11km straight line, 27mghz will not go much further than 8 - 9 km if with tail wind), 6db throws a longer pattern again, the 9 db the ultimate range for outback long distance but anything over 1.2 mtres generally have spring problems if they are used over very corrugated country (they get the wobbles like warm licorice), most good CB fitters don't recommend the 6' aerials for 4WDrives, unless you carry the 4' one for hard country (about $90 just for this replacement size $199 for the 6' one last time I enquired.

[b]<span style="color:blue">UHF definately has more distance than a 27mhz radio </span> mountainous country. 27 mghz relies on boucing signal of clouds and other atmspheres (if clear sky not much good) UHF is direct line of sight, thats why can be a little less favourable in mountain country can't get over the very big hills.

The big problem with 27mghz unless a group of you (mates) all have 27mghz you are the only ones you can talk to hardly used any more by serious off roaders as clarity inferior to UHF.

The other downside is if country areas or travelling the outback no one uses 27mghz in the scrub. In an emergency all properties uses UHF, most pubs monitor UHF (truckies will radio in to have put the steak on) emergency services like Bush Fire all monitor UHF (on the higways you will see signs Report Fires UHF 12 etc), Truckies long hauling do not use 27mghz, none of these do.

So what I'm saying is if you are alone, break down there is some chance of contact to be made with a local farmer (all their tractors, homes and farm vehicles are equipped with UHF not 27mghz, a truck going past may not stop if hailed but may if you ask him to stop when asked on UHF 40 for help (happened to me on Hay Plains no CDMA coverage), a lot of outback areas channel through repeater stations UHF 1 to 6 I think and can forward your signal for 50 - 60 km and are monitered by emergency services, I know outback Highway Patrol Cars near Bourke have them in their cars as we had an interesting conversation on one trip, lucky we said the right thing as he went past :oops:

Sorry didn't mean to run on but worth considering each point especially those with 27 mghz only better to have both like me, but UHF if only one radio, I've had 27mghz back when "Convoy" was the movie to see (about 35 years ago), with my 26 ch Midland SSB, now to my 40ch GE, but has cobwebs on it since the last time I used it if it does work at all?

Bryce 8)

I'm still thinking of putting mine in, space is the big thing or lack of it but would be handy though, mines a Ferris 5000 22 channel (Canadian model) changed slightly with 16 watts output and a 200 channel skanner attached picks up ham channels and is capable of going in between channels as well [img]style_emoticons/<#EMO_DIR#>/biggrin.gif[/img] only have a mobile one 5/8 whip, but it is amazing how good these ariels are.

Baz.

and the memories keep flooding in......


i made quite a few friends over the cb...very similar to the internet and this site....there was no internet back then....

i even met my wife on the damn thing.....dunno if that was good or bad....

<div class='quotetop'>QUOTE</div><div class='quotemain'>i even met my wife on the damn thing...[/b][/quote]

Ha! Do you remember the first eyeball???