使用过时的85053A而不是85053B验证套件有什么优势？

我最近将我的8720D送到英国的安捷伦进行校准。
我大概一周前回来了。
在安捷伦发布的校准证书上：http：//sage.math.washington.edu/home/kirkby/Agilent-standard-calibration-with-uncertainties-for-8720D-vector-network-analyzer.pdf我发现3.5毫米
使用的验证套件是过时的85053A，而不是目前的85053B。
使用该套件优于目前的85053B有什么优势吗？
我想买一个验证套件，所以想知道什么是最好买的型号。
我猜测8720D的校准程序是在85053B可用之前开发的，当过时的85053A完成工作时，安捷伦认为没有理由更新使用当前套件的程序。
但如果使用过时的套件有优势，我会在寻找套件时牢记这一点。
根据我在目前的85053B上可以找到的信息，它确实支持8720系列，所以从表面上看，购买85053B将是更好的选择。
戴夫



     以下为原文

  I recently sent my 8720D to Agilent in the UK for calibration. I got it back a week or so ago.  

On the calibration certificate issued by Agilent:

http://sage.math.washington.edu/home/kirkby/Agilent-standard-calibration-with-uncertainties-for-8720D-vector-network-analyzer.pdf

I noticed the 3.5 mm verification kit used was the obsolete 85053A, not the current 85053B. Is there any advantage in using that kit over the current 85053B? I was thinking of buying a verification kit, so would like to know what's the best model to buy.  

I'm guessing the calibration procedure for the 8720D was developed before the 85053B was available, and Agilent see no reason to update the procedure to use the current kit when the obsolete 85053A does the job. But if there are advantages in using the obsolete kit, I'll bear that in mind when looking for a kit. According to the information I can find on the current 85053B it does support the 8720 series, so on the face of it, buying an 85053B would be a better choice.  

Dave