If you followed the USFL in 1984, a subtle change took place during the middle of the season.  The Pittsburgh Maulers had to change their helmet logo/decal supposedly due to the fact that the orange/purple “Mauler” logo was difficult to see on TV.  At some point in the season the old logo was replaced with a logo that had a white outline around the “Mauler” on the decal.

Here are the differences:

Old logo:  http://www.geocities.com/usflmuseum/84misc/84pmaulersmisc.html

Changed logo:  http://www.misterhabs.com/helmets.htm

If anyone from the Maulers or USFL offices ever finds this post then please leave a comment on the specifics of when/why the exact change was made.  Thanks in advance!