i have a 3.75 khz filter from a sp 401 would like to trade for a 400hz c.w or 3.395 mhz a.m filter for the sp-301 or a manual. Sponsored by the City of Tempe Listserver Submissions: heath at listserv.tempe.gov Listserver Subscription: listserv at listserv.tempe.gov - "subscribe heath 'name' 'call'" Listserver Unsubscribe: listserv at listserv.tempe.gov - -"signoff heath"