[Premium-Rx] What is this? --> Racal MA2232 HF Receiver Tuning Aid

[Martin Colby]

Hi all:

Ran across an epay listing for a "Racal MA2232 HF Receiver Tuning Aid".

Must admit that I haven't the slightest idea what it's for/what it does.... 
(Maybe a preselector of some type or ...) Anyone have any ideas?

BTW, I have nothing to do with the sale (honest!), but if you're curious, 
it can be located at:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3060602930&category=15051

Martin Colby