Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/5/84; site anasazi.UUCP Path: utzoo!watmath!clyde!cbosgd!ihnp4!qantel!lll-crg!seismo!hao!noao!terak!mot!anasazi!john From: john@anasazi.UUCP (John Moore) Newsgroups: net.ham-radio.packet Subject: Re: Icom 2AT PTT Message-ID: <371@anasazi.UUCP> Date: Fri, 15-Nov-85 10:34:13 EST Article-I.D.: anasazi.371 Posted: Fri Nov 15 10:34:13 1985 Date-Received: Mon, 18-Nov-85 07:19:03 EST References: <370@mit-eddie.UUCP> Reply-To: john@anasazi.UUCP (John Moore) Organization: Anasazi, Phoenix Az. Lines: 21 In article <370@mit-eddie.UUCP> GILLMANN@USC-ISIB.ARPA writes: >From: Richard Gillmann >I'm just finishing construction of my TNC2 and I'm trying to figure >out how to interface it to an Icom 2AT handheld. The 2AT doesn't seem >to have a separate PTT line as the TAPR documentation assumes. From I have made a (crude) remote base using the 2AT. It turns out that if you provide a high impedance path from mic audio to ground when you want PTT, and leave it open otherwise, it will work. I think about 10K will do it. To find out, just connect a test resistor from the hot mic lead to ground. Warning: I found out that if you have it "key down" with this method, and you power it off and on, it will come up in a wierd state from which it cannot recover without powering it off, opening the mic lead, and powering it back on. -- John Moore (NJ7E/XE1HDO) {decvax|ihnp4|hao}!noao!terak!anasazi!john {hao!noao|decvax|ihnp4|seismo}!terak!anasazi!john (602) 952-8205 (day or evening) 5302 E. Lafayette Blvd, Phoenix, Az, 85018 (home address)