Re: LF: Re: WSPR OBSERVATIONS

[DK7FC <selberdenken@posteo.de>]

R Mal,

Then i would try the TC4426, if you have them at home. And a ferrite transformer to rise the voltage level a bit and to decouple TX from PA.
https://129.206.22.210:8001/f/80bc50b01d/ for example.
I also prefer Schmitt-trigger based drivers and rectangular input signals.
Just use a scope and watch the output signal of the 4426. Maybe you will need a higher transformation ratio. Or use the ICL7667 if you have one. It can be driven from a 3.3V signal on the input and gives an output sqare wave of abt the supply voltage (I use it as a driver between Raspi and my main MF PA).

73, Stefan

Am 04.12.2015 19:17, schrieb mal hamilton:

Guten Tag Stefan

Main amp is a single Decca 5501 module and has a smit trigeer so can take sine or square wave. I use square wave input for Opera and QRSS because of the divide down from 5 Mhz main VFO. The input to main amp needs around 7 – 10 volts. At present I use VFO 472 – 479 Khz /4001(SQUARER)/4017 DIVIDE BY 10/tc4426 driver to main 5501 amp input

 

73 de mal/g3kev

 

 

 

From: DK7FC

Sent: Friday, December 04, 2015 5:07 PM

To: rsgb_lf_group@blacksheep.org

Subject: Re: LF: WSPR OBSERVATIONS

 

Am 04.12.2015 17:53, schrieb mal hamilton:

[...]

 

When I get time I will QRO but need to build an intermediate RF amp between TCVR and main MF amp

Which input signal does your main MF amp need? Rectangular? Sine? Which input-Z? Which amplitude?

73, Stefan