-----Original Message-----
From: John Miller [mailto:[log in to unmask]] 
Sent: Sunday, May 16, 2010 3:03 PM
To: [log in to unmask]
Subject: Re: amplifier use questions

Once you get used to it, you can tune up an amp in 5 seconds or less, I can 
do it with my SB200 heathkit. I can get a lot out of that with the 572B's 
but try to keep it around 500 watts though now that I have the apartment I'm

going to probably not run it much if at all.
----- Original Message ----- 
From: "Lloyd Rasmussen" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, May 16, 2010 2:47 PM
Subject: Re: amplifier use questions


> Obviously, if you want to switch bands quickly during a contest, an amp 
> with
> plate tuning and loading controls and a bandswitch will slow you down a
> little.  But it doesn't prevent me from doing fairly well in contests.
>
> I use a 39-year-old Yaesu FL2500 amplifier (which uses five 6KD6 
> horizontal
> output tubes in parallel and struggles to get much more than 500 watts PEP
> output.  A rather low-impedance, low-voltage, somewhat inefficient 
> circuit.
> The manual recommends no more than five seconds of continuous carrier at 
> the
> SSB full-power setting.  Failure to observe this precaution may result in
> destination of the tubes!  (A bad Japanese translation).
>
> I used to tune this up with a Conway gimick, and now tune it up with the 
> LDG
> TW-1 wattmeter on the tone setting.  I tune for "maximum smoke" (max RF
> output).  I have to make my FT950 tune up into the linear amplifier's 
> input
> circuit, since the impedance is somewhat lower than 50 ohms.  It requires
> about 50 watts of driving power.
>
> If you get an amp with a real output tube or tubes, such as the 3-500Z or 
> a
> set of 811A's, the amp will be more rugged than mine.
>
> Last Sunday you heard this setup on the 20-meter net.
>
> If you have any other questions, please let me know.
> 73,
> Lloyd Rasmussen, W3IUU, Kensington, Maryland
> Home:  http://lras.home.sprynet.com
> Work:  http://www.loc.gov/nls
>
>> -----Original Message-----
>> From: For blind ham radio operators 
>> [mailto:[log in to unmask]]
>> On Behalf Of Gary Lee
>> Sent: Saturday, May 15, 2010 11:14 PM
>> To: [log in to unmask]
>> Subject: amplifier use questions
>>
>> I have never used an amplifier before, but am now considering purchasing
>> one.
>>
>> There are some nice no tune solid state amps out there, but they are
>> pricy.
>> What is the general experience out there with using tube type amps and
>> tuning them up?
>>
>> I am thinking about something in the 5 or 600 watt range.
>>
>> I would appreciate any information and experiences.
>>
>> 73