Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Lagondanet]

Anyone any idea what kind of aerial this is and what it might have been used for?

https://www.dropbox.com/s/ll23krwt15u9942/Central%20Bedfordshire-20140301-00793.jpg

[05omegav6]

Pop the sunroof switch panel/motor cover off to see which side of the car it runs to, then have a rummage in the appropriate footwell, might find an identifiable plug on the end of it

[zirk]

Its a 1/4 Wave Whip on a M5 50 Ohm Base, by the lentgh of it I would say for UHF (Lower end) Radio Comms or could be Tertra (Dolphin or Airwave) but doesn't look long enough to me.

If you measured the whip length (from where the top of the plastic base meets the hinge part) to the top of the whip (the plastic cap pulls off) I could work out its frequency and give you a better idea what it was used for, assuming of course who ever installed it, knew what they where doing.   

[dbug]

Anyone any idea what kind of aerial this is and what it might have been used for?

https://www.dropbox.com/s/ll23krwt15u9942/Central%20Bedfordshire-20140301-00793.jpg

 

[Lagondanet]

Zirk

The whip length is 10.50 cm.

[zirk]

Zirk

The whip length is 10.50 cm.

No its not, I can tell its more than that just by looking at the picture. 

[zirk]

As in my earlier post, are you measuring it from the top of the plastic Base, ie where the plactic base meets the lower metal hinge base to the top of the whip, in other words the hinge lower part and the whip holder form part of the overall lenght. 

[Lagondanet]

I thought I might have had too much peach schnapps but have just measured it again with the top off to the top of the plastic cone (which unscrews) on the hinge. That is still 10.50?

[Lagondanet]

I suppose what I would call the plastic cone at the base of the whip and attached to the hinge would add another 3 cm.

[zirk]

[Lagondanet]

Nice picture Zirk. I'll get back to you this evening. Thanks for being gentle with me.

[Lagondanet]

13.50!

[zirk]

Works out to around 472 Mhz, so just at the top end of the Public available UHF Spectrum, (419 - 474) so probably a PMR or PAMR use.

Once you go above 474 Mhz, it goes Militry or MOD untill you hit the TV DVB Band a bit futher up. There is also some old Goverment and or Broadcast fixed links channels in there but we wont go into that one.

[Lagondanet]

Thank you Zirk. I am in awe of your knowledge. I will let you know if I find out any more.

[zirk]

Thank you Zirk. I am in awe of your knowledge. I will let you know if I find out any more.

Your welcome, bet you wished you never axked now. 

[minifreek]

Zirk.... are you a RadioHam...? Im a 2E0 but studying for my advanced later on in the year to get my Dads G6 call

[zirk]

Zirk.... are you a RadioHam...? Im a 2E0 but studying for my advanced later on in the year to get my Dads G6 call

No, well, kind of No. 

last 35 years in the Radio Comms and Telecomms Industry, prior to that Sound Engineer, then Audio and Hi Fi.

Seem to remember I had one of those G8 Licences moons ago, but that all got thrown out the window (literally) when you have to work in the game.   

[Lagondanet]

Member of first owner's family says it was used for a car tracking/security service. My earlier Omega (This/current one is 2002) had 'Tracker' fitted but with no visible aerial.

[zirk]

Member of first owner's family says it was used for a car tracking/security service. My earlier Omega (This/current one is 2002) had 'Tracker' fitted but with no visible aerial.

Probably used on the Securicor Datatrak Service then. Securicor developed their own AVL Service in the UK for their own Security Vans when early GPS System was deemed patchy or unreliable for non Military use. The Vans would pick up HF Beacons around the Country, calculated its position then transmit the Data back to Securicor Control Rooms via its own UHF Radio Network.

Having built its owm AVL Service, Securicor Datatrak would also Sub Rent its Services to 3rd Party Firms for increased revenue.

The System you had fitted, Tracker, was slightly different design, in as much a Tracker (AVL with Open Transmitter Data) would be hidden in the Vehicle, then activated by forced entry or remotely, transmit its location in real time on an open common frequencies so that the Police, Recovery or the Tracker Control Rooms could receive and Track the Data from the Vehicle. 

 

[Steve B]

Zirk.... are you a RadioHam...? Im a 2E0 but studying for my advanced later on in the year to get my Dads G6 call

No, well, kind of No. 

last 35 years in the Radio Comms and Telecomms Industry, prior to that Sound Engineer, then Audio and Hi Fi.

Seem to remember I had one of those G8 Licences moons ago, but that all got thrown out the window (literally) when you have to work in the game.   

Sorry for going off Topic.. Zirk why do these technics hifi amps IE:-SU-X902 (class A) and a few more ive had in the past always have the fan that is controlled by temp pack up, But its never the fan,But the board that runs it