Absolutely, Don. Also, resist the temptation of putting a second LP filter
after the amp. Someone mentioned that by doing so would tend to make things
worse.
Bob W7KD
----- Original Message -----
From: "Don Havlicek" <n8de@thepoint.net>
To: "David Thompson" <thompson@mindspring.com>
Cc: <towertalk@contesting.com>
Sent: Tuesday, August 16, 2005 1:10 PM
Subject: Re: [TowerTalk] Are All Low-Pass Filters Alike? -
> Why don't hams place the LP filter between the Xcvr and the Amp? That
> way, the amount of harmonics reaching the Amp will be minimized,
> rendering their output levels relatively the same, if not lower, than if
> the LP filter was AFTER the Amp.
> BTW: this is what I have done since the 50's. Never blew up a LP
> filter yet!
> Don
> N8DE
>
> David Thompson wrote:
>> I have a Drake TV-3300-LP that went south while operating 40 meters with
>> my
>> 8877 AMP running 1400 watts out. Reading the filter its 1000 W Max which
>> I
>> assume is input not output. The coil in the filter melted at one end and
>> now rattles around inside the filter.
>>
>> I also remember a B&W 1KW LP filter that arced over inside back in the
>> late
>> 60'S. I had been using it with a single 4-400A amp at about 800 to 1000W
>> pep
>> and the first transmission with a then new NCL-2000
>> amp cooked it. Turns out they used this black plastic
>> as an insulator. I doubled the plastic and it still works
>> fine with my 500 watt spare amp.
>>
>> Marshall Emm at Morse-X/Milestone Technologies bought AMECO two years ago
>> and might be able to
>> answer questions on the AMECO filter. HE has a web page for MOrse-X. I
>> suspect its of the same design as the B&W and the Drake and designed for
>> the old KW input limit.
>>
>> I do agree with K1TTT that they are probably not needed much today but
>> they
>> sure make you feel more comfortable especially on 15, 12, and 10.
>>
>> Dave K4JRB
>>
>>
>> _______________________________________________
>>
>> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
>> any questions and ask for Sherman, W2FLA.
>>
>> _______________________________________________
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>>
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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