after about 30 years I acquired another VLF 710. this one needs repair. taking it apart to double check any obvious problems I noticed that it does not have the inner foil shield that my other VLF 710 has. since I do not have both of them running I cannot compare. but wondering what advantage or disadvantage does this foil shield have? I have owned numerous Wilson's over the years and do not recall this foil shield in any except for the VLF 710. so any info would be appreciated. thanks