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#1
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#2
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#3
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![]() One other oddity. Before I power up the radio, the amp is drawing zero current. As soon as I power up the radio (on RX), the amp starts drawing 180 ma, whether it is switched on or off. Impossible. The amp has no input for the powered condition of the radio (receive). Do you have the coax in-out connected backwards? |
#5
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On Thu, 26 Feb 2004 20:58:19 -0800, Frank Gilliland
wrote: In , wrote: One other oddity. Before I power up the radio, the amp is drawing zero current. As soon as I power up the radio (on RX), the amp starts drawing 180 ma, whether it is switched on or off. Impossible. The amp has no input for the powered condition of the radio (receive). Wrong -- it's very possible. That is a MOSFET amp with no power switch. A bad combination to be sure, because as long as there is source-drain voltage, any kind of signal can drive it to some extent. It's possible that C1 could be shorted (after all, it's only rated for 50 volts) and the output of the radio have a DC component. Or if D2 is blown (a 1N4148 passing 3 watts -- yikes!) D1 will hold a nice, steady DC bias on the MOSFET. There are a lot of possible scenarios for what he is describing. What -is- impossible is for you to think before you demonstrate your ignorance. Haven't we been through this before, Tnom? Didn't you learn anything the first dozen times? But hey, it's a cheap and crappy amp, and you get what you pay for. Do you have the coax in-out connected backwards? You have your brain connected backwards. Quit trying to act like you know what you are talking about. I stand by my post. There is no voltage on the radios coax on receive that will activate the amps increase in current draw. You should pay more attention. Even if there was a DC voltage C1 on the amp would block it. "You have your brain connected backwards. Quit trying to act like you know what you are talking about." I just couldn't resist. http://www.rmitaly.com/download/inst...nstruction.pdf |
#6
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On Fri, 27 Feb 2004 05:14:24 -0500, wrote:
On Thu, 26 Feb 2004 20:58:19 -0800, Frank Gilliland wrote: In , wrote: One other oddity. Before I power up the radio, the amp is drawing zero current. As soon as I power up the radio (on RX), the amp starts drawing 180 ma, whether it is switched on or off. Impossible. The amp has no input for the powered condition of the radio (receive). Wrong -- it's very possible. That is a MOSFET amp with no power switch. A bad combination to be sure, because as long as there is source-drain voltage, any kind of signal can drive it to some extent. It's possible that C1 could be shorted (after all, it's only rated for 50 volts) and the output of the radio have a DC component. Or if D2 is blown (a 1N4148 passing 3 watts -- yikes!) D1 will hold a nice, steady DC bias on the MOSFET. There are a lot of possible scenarios for what he is describing. What -is- impossible is for you to think before you demonstrate your ignorance. Haven't we been through this before, Tnom? Didn't you learn anything the first dozen times? But hey, it's a cheap and crappy amp, and you get what you pay for. Do you have the coax in-out connected backwards? You have your brain connected backwards. Quit trying to act like you know what you are talking about. I stand by my post. There is no voltage on the radios coax on receive that will activate the amps increase in current draw. You should pay more attention. Even if there was a DC voltage C1 on the amp would block it. I forgot to mention.....C1 can't be shorted on all three amps "You have your brain connected backwards. Quit trying to act like you know what you are talking about." I just couldn't resist. http://www.rmitaly.com/download/inst...nstruction.pdf |
#7
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In , wrote:
On Fri, 27 Feb 2004 05:14:24 -0500, wrote: snip I forgot to mention.....C1 can't be shorted on all three amps It can if the cause of the short is common to all three amps, such as a fault in the radio testing the amps. I guess you -didn't- learn the first dozen times. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#8
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![]() From: =A0=A0 Frank Gilliland Group: =A0=A0 rec.radio.cb Subject: =A0=A0 KL40 amp problems Date: =A0=A0 Thu, Feb 26, 2004, 8:58pm (EST-3) X-Trace: =A0=A0 corp.newsgroups.com 1077857940 216.64.140.70 (26 Feb 2004 22:59:00 -0600) X-Comments: =A0=A0 This message was posted through A href X-Comments2: =A0=A0 IMPORTANT: Newsfeed.com does not condone, X-Report: =A0=A0 Please report illegal or inappropriate use to X-Comments3: =A0=A0 A href =3D"http://www.newsgroups.com"Visit Organization: =A0=A0 Newsfeeds.com http://www.newsfeeds.com 100,000+ UNCENSORED Newsgroups. In , wrote: One other oddity. Before I power up the radio, the amp is drawing zero current. As soon as I power up the radio (on RX), the amp starts drawing 180 ma, whether it is switched on or off. (=A0=A0Impossible. The amp has no input for the powered condition of the radio (receive). ) Wrong -- it's very possible. That is a MOSFET amp with no power switch. A bad combination to be sure, because as long as there is source-drain voltage, any kind of signal can drive it to some extent. It's possible that C1 could be shorted (after all, it's only rated for 50 volts) and the output of the radio have a DC component. Or if D2 is blown (a 1N4148 passing 3 watts -- yikes!) D1 will hold a nice, steady DC bias on the MOSFET. There are a lot of possible scenarios for what he is describing. What -is- impossible is for you to think before you demonstrate your ignorance. Heal thyself. In the first manner, there is no need for projected disdain and insult towards one who you disagre with. Keeping wiht the subject of the group and discussing the electronic possibilities that may or may not be wrong without insult is a good way to try and lose the deficit in communication you portray that has you becoming an insultive jack ass to a poster in a group for merely offering a differing point of =3Dview than yourself. Your level of intolerance for differing views llustrates your true level of intellect and communication skills. The chance of probablility you offer concerning your weak input concerning all three amps having the same short is ridiculous, like most of your ignorant and abusive posts that were responsible for you having no choice but to subscribe to a pay access in order to access the group in the most obsessive manner. The likelihood of one individual being correct increases in a direct proportion to the intensity with which others try to prove him wrong |
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