Re: Transmit a continuous tone for PA adjustment


Rubens Kamimura
 

Hello everyone

Now I have a little problem of power fluctuation in FT8, I only tested in FT8 in 40m, resting current (Ibias) in 100mA, in the IRF510, powered with 13.8VDC, will the length of the interconnection cable of the board with connectors, is bringing feedback interference? Hans Summers (qrp-labs.com), always warns us, to take care of unwanted feedbacks. Would that be the case?
73 de Rubens py2pvb

Em sex., 8 de jan. de 2021 às 10:03, Gordon Gibby <docvacuumtubes@...> escreveu:

If you set up high speed electronic keying of “dots”, you can obtain stable readings on analog scales, while reducing the dissipation of the final amplifier by 50%

People sometimes use this to protect expensive devices while tuning.


Gordon
> On Jan 8, 2021, at 07:24, Rafael Diniz <rafael@...> wrote:
>
> Perfect, I just realized that, thanks!!
>
> Rafael
>
>> On 1/8/21 12:15 AM, Ashhar Farhan wrote:
>> If you put the latest firmware into the ubitx, you can key cw by
>> holding down the mic ptt
>>
>> On Fri 8 Jan, 2021, 8:25 AM Curt via groups.io <http://groups.io>,
>> <wb8yyy=yahoo.com@groups.io <mailto:yahoo.com@groups.io>> wrote:
>>
>>    Yes. With older vacuum tube transmitters we used a key to tune the
>>    final amplifier. As Mark suggests, need to set menu for hand key,
>>    as the paddle or keyer mode produces continuous dits or dahs instead.
>>
>>    I am remembering wsjtx software for ft8 has a tune function,
>>    which gives a steady audio tone as Rubens suggested. Try all of these.
>>
>>    Curt
>>
>>
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