A 1A2 panel recently ended on eBay unsold. Each of the 400D KTUs was modified, looks like a resistor/diode was added. A small hole was made in the plastic front for one of the leads. Check out the picture by searching ebay for item # 281390634430. Anyone have an answer for the purpose of the modification? Never came across this before. Thanks for checking Jim

[img]https://www.ebay.com/itm/Western-Electric-1a2-key-system-parts-as-s-Power-supplies-line-cards-etc-/281390634430?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2047675.l2557&nma=true&si=fMo5O9wJjfZ5ON3Ehsa9vYI1%252FDk%253D&orig_cvip=true&rt=nc[/img]