I've roughed out a serial number list for Rockford movements above 824000. Roy Ehrhardt has previously published a similar list, but since mine was arrived at using data totally independent of his it may be of some additional benefit to the Rockford collecting community. I also hope that, in the long run, it will turn out to be more complete and accurate.
just follow the link
The middle part of the Rockford serial number list (approx. 200,000 to 824,000), which was compiled by the company itself and published in their material catalogs, is reasonably accurate, but it does have a few gaps that need to be filled in and some errors (e. g. the grade 501 typo). I have collected some data for this region as well that will be posted in the near future.
The early part of Rockford's production is problematic and will require large amounts of data to get a reasonable handle on. Roger Weiss has been working on this area for many years.
Anyway, just some info for the interested Rockford buffs out there.
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