Re: [softrock40] First success!
- Hi Phil,The HP function generator should be set to about 1 mV RMS or less at a frequency slightly above or below each center frequency, (oscillator frequency divided by 4), to test the RX function. Ground loops may cause additional noise on the spectrum display but for initial testing it should be ok without isolation transformers.73,Tony KB9YIG----- Original Message -----From: d7o3g4qSent: Thursday, August 30, 2007 1:11 PMSubject: [softrock40] First success!
I built the daughterboard for my 20/30 RXTX kit. Fortunately for me,
here at work we employ an EE and he has all sorts of really nice
equipment. We tested the daughterboard with a current limited power
supply, hooked up the o-scope and received a very nice waveform. The
waveform measured correctly for both jumper settings.
I'm going to start the mainboard soon. I did have one question
though. He has a function generator with which I can generate a sine
wave up to 15 MHZ. I was wondering if its possible to use it to test
RX once the mainboard is done. Would it be possible to hook it up as
the antenna input and if so, what should I use as an output amplitude
(? volts p-p)? The voltage setting assumes 50 ohm termination. Do I
need to worry about ground loops and if so should I use an isolation
transformer? The function generator is a Hewlett Packard 33120A
Thanks for the advice and thanks for the kit. I haven't had this much
fun in a while!