Hi Todd, A rough rule-of-thumb to help get you started in your choice of tube(s) is the following: your carrier OUTPUT---when the linear amplifier is used as such, i.e. to boost the AM signal driving it from your exciter---is equal to ONE HALF of the plate dissipation of your tubes...
I have a pair of G-G 813s in my HB kilowatt: each 813 is good for 125 watts of plate dissipation, so one tube alone would be good for 62.5 watts of carrier output in AM linear mode...the pair of them gives me a total of 125-watts of carrier, with a drive of some modulated 15 watts, or so, at the linear's input jack... No, it may not be "as good" to the purists as a full-bore 200 watt plate carrier modulated by some 100 watts of P-P class B audio, but it'll STILL make your presence on the band known, and in pretty good fashion, too... Besides, have you seen many 100 watt plate modulation transformers for sale anywhere lately...?! ~73~ de Eddy VE3CUI - VE3XZ ****************************** ----- Original Message ----- From: "Todd Carpenter" <[email protected]> To: <[email protected]> Sent: Monday, October 05, 2009 10:29 AM Subject: [AMRadio] Any amplifier suggestions? > I am interested is a simple design hf amplifier for am cw on 160-80/75-40. These are the bands i operate on where the extra power would help. Fewer parts count the better. Ultimately lower cost the better. I have power supply parts and believe that i can generate around 2000 volts. I am slowly researching tubes and am leaning toward 2 or 4 tubes that can basically generate lots of watts at half to two thirds their ratings to prolong their life span. Perhaps tubes such as 811's, 810's, 833's, 4-400's. I am open to suggestions. I will need to build or acquire a heavy duty matching system as part of the amp. My goal is at least 300 Watts AM. I do not want to mess with systems that require cooling other than fans. I am not interested in modes for this amp other than am and cw. It will almost exclusively be used for am as i rarely use more than 5 watts on cw any way. Simpler cheaper is better for me. I appreciate your suggestions. Todd > ______________________________________________________________ > 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 > Post: [email protected] > To unsubscribe, send an email to [email protected] with > the word unsubscribe in the message body. > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ 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 Post: [email protected] To unsubscribe, send an email to [email protected] with the word unsubscribe in the message body. This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
