I believe, don't have supporting docs to hand, the GRR-5 was an "alert receiver", same use as the ? BC-728 ? SCR-593 ? "air warning receiver" seen in a WW2 photo or 2. Sent from my Galaxy -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20251021/6dd8a8e0/attachment.html>