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SPCh · 16th Nov 2006, 12:16 pm

Paul,
Your gifted Model 7 has already been entered in the survey by its previous owner. In fact it's a bit of a problem item, because the serial number, 69847-7475, doesn't sound right at all. The date code would imply April 1975, which is far too late for a number in a format which was changed in 1947. It's possible that the number was written with digit reversal - I've seen odd instances of that - but even at May 1947 there's still a problem: in July 1947 the sequence numbers were still "only" in the 36,000s. The sequence number alone would imply late 1956 but, of course, the format would then be nine years adrift.

Clues on the outside are the terminal style (black knurled screws or red and black socketed-screws), and whether there are "P.F." sockets at the top corners. I would never recommend opening a meter out of curiousity, but if you ever have to repair it, I'd be interested to know what type of magnet it has (black horseshoe or a possibly coloured block type), the colour of the plastic sleeving, and what sort of resistors predominate. There may also be a production date on the large 1 microfarad paper capacitor.

This enigma is part of what the survey is about !!!

16th Nov 2006, 12:16 pm	#152
SPCh Rest in Peace Join Date: Nov 2004 Location: Antwerp, Belgium Posts: 345	Re: AVO Multimeter survey Paul, Your gifted Model 7 has already been entered in the survey by its previous owner. In fact it's a bit of a problem item, because the serial number, 69847-7475, doesn't sound right at all. The date code would imply April 1975, which is far too late for a number in a format which was changed in 1947. It's possible that the number was written with digit reversal - I've seen odd instances of that - but even at May 1947 there's still a problem: in July 1947 the sequence numbers were still "only" in the 36,000s. The sequence number alone would imply late 1956 but, of course, the format would then be nine years adrift. Clues on the outside are the terminal style (black knurled screws or red and black socketed-screws), and whether there are "P.F." sockets at the top corners. I would never recommend opening a meter out of curiousity, but if you ever have to repair it, I'd be interested to know what type of magnet it has (black horseshoe or a possibly coloured block type), the colour of the plastic sleeving, and what sort of resistors predominate. There may also be a production date on the large 1 microfarad paper capacitor. This enigma is part of what the survey is about !!!