UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - 405-Line VHF Aerials 2013 to the present day.

SteveCG · 21st Aug 2014, 11:19 am

Re post no. 178

Steve FPV, yes, the aerial on St Andrews Rd is the one I was thinking about. Other properties on that little bungalow estate also had different types of J Beam Band I and Band III aerials, but going digital seems to have cleared them all away to the big skip in the sky.

I reckon the larger West Malvern, near the Brewers Arms, aerial is an Antiference Band II (ie VHF/FM) aerial, put up after Ridge Hill went mixed polarization. I presume the fact that it is not pointing in the same direction as the, what looks to be wideband, UHF design just demonstrates the broad forward polar diagram of 3 el. designs. I can't think of a V. Pol only transmitter in that direction, so perhaps somebody fitting it was just making use of the short mounting pole. Multi-path performance (quite an issue around the Malvern Hills) would likely to be better in the H. Pol mode of use.

The Winchcome UHF arrays are early (circa 1964 to 67?) Antiference designs. The clue is the type and under-side position of the junction boxes.

The Band III double in pic no 3 is a Labgear design. Quite possibly the Band I is a also a Labgear 1/4 wave. A close-up pic of the junction box could confirm as they were distinctive.
The Band III double in pic no. 4 looks like a Telerection jobbie - looks impressive, but almost impossible to dismantle and not a great performer.

Finally, I've seen other aerial systems where the Band I & III aerials have been demoted in height with the arrival of the new UHF 'baby'.

21st Aug 2014, 11:19 am	#179
SteveCG Nonode Join Date: Jun 2009 Location: Herefordshire, UK. Posts: 2,495	Re: 405-Line VHF Aerials in 2013-2014 Re post no. 178 Steve FPV, yes, the aerial on St Andrews Rd is the one I was thinking about. Other properties on that little bungalow estate also had different types of J Beam Band I and Band III aerials, but going digital seems to have cleared them all away to the big skip in the sky. I reckon the larger West Malvern, near the Brewers Arms, aerial is an Antiference Band II (ie VHF/FM) aerial, put up after Ridge Hill went mixed polarization. I presume the fact that it is not pointing in the same direction as the, what looks to be wideband, UHF design just demonstrates the broad forward polar diagram of 3 el. designs. I can't think of a V. Pol only transmitter in that direction, so perhaps somebody fitting it was just making use of the short mounting pole. Multi-path performance (quite an issue around the Malvern Hills) would likely to be better in the H. Pol mode of use. The Winchcome UHF arrays are early (circa 1964 to 67?) Antiference designs. The clue is the type and under-side position of the junction boxes. The Band III double in pic no 3 is a Labgear design. Quite possibly the Band I is a also a Labgear 1/4 wave. A close-up pic of the junction box could confirm as they were distinctive. The Band III double in pic no. 4 looks like a Telerection jobbie - looks impressive, but almost impossible to dismantle and not a great performer. Finally, I've seen other aerial systems where the Band I & III aerials have been demoted in height with the arrival of the new UHF 'baby'.