John, I have not had a SB 200 in A.M. service, but have used a 811 three tube model with a Kenwood 140S and a D-104. Received great reports on 75 meters and 40 meters using a 75 meter dipole and 450 ohm latter line. The 140 has a adjustable power output control , and I would load the amp after tuning with about 20 to 30 watts and get out 200 watt or so, could do more if needed, however, not much gain between 200 and 300 watts. Trick seems to be getting a good mike with wide freq range and adjusting mike gain to keep it within the ALC, watch you output meter in the tuner and keep it swinging forward at voice peaks, should it stop swinging forward your hitting it too hard, back off the mike or the gain. 73 have fun
Bob Carpenter KB4wec -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John Lawson Sent: Tuesday, June 10, 2008 2:27 PM To: [email protected] Subject: [AMRadio] SB-200 on AM I have found (and hauled home) a slightly-ailing SB-200 amp that I would like to use on AM... I'll be driving it with an Alinco DX-70 (40W AM/CW), into an ATR-15 tuner, thence by ladder-line out to my "Sort-Of-NVIS Loop", the which system right now tunes 75 Fone down to 1.1:1 very stably and reliably. Aside from the many pages of mods and tweaks, does anyone have any comments/experiences - good-bad-ugly - ? My previous AM rig was a Valiant - I've not had a separate amplifier since I sold off all my S-Line gear back in the late 80s. Thanks in advance for any info or thoughts on the SB-200 in AM service. Cheers John KB6SCO Carson City, NV ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body. ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
