On Mar 7, 2006, at 5:55 PM, Dan Sawyer wrote:
> Should mix 67 support a 1.8 to 55 MHz 1200 watt transformer?
Yes, however the fly in the pie for mu=40 material is whether or not a
winding that has sufficient L for 1.8MHz will not have too much C for
55MHz.
>
> On this topic:
> ??? 1. What physical form should be used?
> ??? 2. What is a reasonable turns on the 50 Ohm side (to start
> design).
I think the generator end is the place to start from.
>
> Dan
>
> R@contesting.com;Measures wrote:On Mar 7, 2006, at 9:03 AM, Jim Brown
> wrote:
>>
>>
>>> On Tue, 7 Mar 2006 08:56:08 -0800, R@contesting.com;Measures wrote:
>>>
>>>
>>>> On an oscilloscope, using 100w of RF, I observed that mix #61 begins
>>>> to
>>>> distort the waveform at c. 13MHz. Those who don't desire to
>>>> generate
>>>> harmonics should probably follow the manufacturer's specs and not
>>>> operate 61 above 10MHz.
>>>>
>>> The distortion and losses will depend on many variables, including
>>> the
>>> power level, the size of the core, and the number of turns.
>>>
>> Agreed. Waveform distortion is the result of of a combination of too
>> many Webers and too much f.
>>
>>
>>> What were your
>>> test conditions (core size, turns, etc.)?
>>>
>> I don't remember the details, Jim, however, as I recall it was a 2.4"
>> mix-61, mu=125, core for a 450-ohm 8170 grid terminator R. Whereas
>> everything looked wonderful on the 'scope at 1W, at 100W, it did not.
>> After I read Permag Pacific's tech specs on mix-61, it was apparent
>> that the seller didn't. As a result of seeing the harmonic distortion
>> above 13MHz with 100W, I switched to mix-67 (mu=40, rated by mfg at
>> 80MHz max) and observed a clean sinewave at 29MHz.
>>
>>> Jim Brown K9YC
>>>
>>>
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>>
>>
>>
>> Rich Measures, 805.386.3734, AG6K, www.somis.org
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>>
Rich Measures, 805.386.3734, AG6K, www.somis.org
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|